IDIDAS SIT Glossary

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Term	Definition
aberration	Any body, form (shape) or structure that deviates from the normal or typical condition (Gordh and Headrick 2001). A form that departs in some striking way from the normal type, occurring either singly, or rarely, at irregular intervals (Torre-Bueno 1978).
absolute density	Density of a population expressed as an absolute number per ground-surface area or per unit of volume (Pedigo 2002). Density of a population expressed as every individual of a population within a volume of habitat [paraphrased] (Daly et al. 1998).
absorbed dose	Quantity of radiating energy (in gray) absorbed per unit of mass of a specified target (FAO 2006).
absorbed-dose distribution	A representation of the variation of absorbed dose with position in any region of an irradiated object, e.g. within an insect canister exposed to ionizing radiation (Borders 1991).
absorbed-dose mapping	Measurement of absorbed dose within process load [an irradiated material/sample, e.g. insect canister] using dosimeters placed at specified locations to produce a one-, two- or three-dimensional distribution of absorbed dose, thus rendering a map of absorbed-dose values (ISO/ASTM 2004a).
absorbed-dose rate	Quotient of absorbed dose per unit of time, unit: Gy/h (Koelzer 2008, Borders 1991). The absorbed-dose rate is often specified in terms of its average value over longer time intervals, e.g. in units of Gy/min or Gy/h (ICRU). The absorbed dose in a material per incremental time interval, i.e. the absorbed-dose rate is the quotient of dD by dt. SI Unit = Gy•s-1 (ICRU) (ISO/ASTM 2004a).
accelerator	See ‘electron accelerator’.
accessory gland	Any secondary gland of a glandular system (Resh and Cardé 2003, Gordh and Headrick 2001). A secretory organ associated with the reproductive system (Borror et al. 1989, Leak 1999, Wall and Shearer 1997). Glandular structure associated with the spermatheca that produces a material that accompanies the sperm during ejaculation (FAO/IAEA/USDA 2003). Male accessory gland = Secretory gland associated with the male reproductive tract that produces seminal fluid and the structural components of the spermatophore (Resh and Cardé 2003, Gordh and Headrick 2001). See ‘spermatheca’, ‘spermatophore’, ‘refractory’.
acclimatization	Habituation/adjustment of an organism to different environmental conditions (Gordh and Headrick 2001, Resh and Cardé 2003). A process that gradually shifts the optimal performance of insects from the extreme limits to the preferred range of colonization. Acclimatization occurs within variable time limits, which are very much shorter than the evolutionary time scale (C. Calkins, personal communication). See ‘colonization’.
acentric	Designating a chromatid or a chromosome that lacks a centromere (King et al. 2006). This condition may arise in an inversion heterozygote as a result of crossing over between a normal and an inverted segment that does not include the centromere (Schlindwein 2006). A chromosome, or chromosome fragment, that lacks a centromere (Hoy 2003). See ‘centromere’, ‘dicentric’, ‘monocentric’, ‘holokinetic’, ‘monokinetic’.
achiasmate	Referring to meiosis without chiasmata. In those species in which crossing over is limited to one sex, the achiasmate meiosis generally occurs in the heterogametic sex (King et al. 2006). No cross-shaped union of chromosomes during nuclear division (Leak 1999).
acoustical signal	An insect communicating with another using sound (Sivinski et al. 1989). See ‘chemical communication’.
acrylamide gel	Acrylamide or acrylamide monomer is the trivial name for propenamide, a water-soluble solid that is highly toxic and irritant, and readily polymerizes under the action of UV light or chemical catalysts into polyacrylamide (Oxford 2006). Polyacrylamide gel is prepared by mixing a monomer (acrylamide) with a cross-linking agent (N,N′-methylenebisacrylamide) in the presence of a polymerizing agent. An insoluble three-dimensional network of monomer chains is formed. In water, the network becomes hydrated. Depending upon the relative proportions of the ingredients, it is possible to prepare gels with different pore sizes. The gels can then be used to separate biological molecules like proteins of a given range of sizes (King et al. 2006). See ‘gel electrophoresis’.
adenotrophic viviparity	A method of viviparous reproduction restricted to pupiparous Diptera. The egg hatches inside the mother and the larva feeds on uterine secretions produced by the mother. Pupation occurs shortly after larviposition (Gordh and Headrick 2001, Leak 1999). Reproduction in which the female gives birth to a larva which developed and has been nourished within the mother’s uterus (Leak 1999). The production of live offspring, where eggs are retained within the female oviduct until the larvae are mature at which stage they are laid and immediately pupate (Wall and Shearer 1997). A phenomenon in certain insects whereby the larvae are retained in the parent’s body after hatching, develop by feeding on ‘uterine’ secretions, moult twice and are finally deposited in a mature state ready for pupation (Leftwich 1976). See ‘gestation’, ‘larviposition’, ‘larviparous’, ‘viviparous’.
adjuvant	Any ingredient that improves the properties of a pesticide formulation (Pedigo 2002). Any ingredient that improves the solubility or handling properties of a pesticide formulation. Adjuvants are sometimes called “stickers” or “spreaders” (Gordh and Headrick 2001). An additive used in conjunction with an active substance, e.g. a biopesticide, to enhance its performance (Coombs and Hall 1998). Chemical combined with insecticide to improve its storage, safety, or effectiveness (Daly et al. 1998). A spray additive to improve either physical or chemical properties (Hill 1997). See ‘chemical control’.
adulticide	A substance, e.g. pesticide, that kills the adult stage of a pest or parasite (NAL 2008). See ‘larvicide’, ‘parasiticide’, ‘trypanocide’.
advanced very-high-resolution radiometer (AVHRR)	A radiometer is an instrument for detecting or measuring radiation (Oxford 2008). The AVHRR is located on a satellite circling the earth (Cox and Vreysen, this volume).
aerial release	Release of insects, e.g. sterile insects, from the air using aircraft. Refer to Dowell et al. (section 5.3.) (this volume). See ‘release’, ‘ground release’, ‘static release’.
aerial spray	Pesticide spray treatment of land from the air using aircraft. Refer to Mangan (this volume). See ‘ground spray’, ‘sequential aerosol technique (SAT)’, ‘chemical control’.
African animal trypanosomosis (AAT)	African animal trypanosomiasis [trypanosomosis] (AAT) is a disease complex caused by tsetse-fly-transmitted Trypanosoma congolense Broden, T. vivax Ziemann, or T. brucei brucei Plimmer and Bradford, or simultaneous infection with one or more of these trypanosomes. African animal trypanosomiasis is most important in cattle, but can cause serious losses in pigs, camels, goats, and sheep. Infection of cattle by one or more of the three African animal trypanosomes results in subacute, acute, or chronic disease characterized by intermittent fever, anemia, occasional diarrhea, and rapid loss of condition, and often terminates in death. In southern Africa the disease is widely known as nagana (USAHA 1998). Tsetse-transmitted [Glossina] trypanosomiasis is an infectious disease unique to Africa and caused by various species of blood parasites. The disease affects both people [Human African Trypanosomiasis (HAT) or sleeping sickness] (Pentreath and Kennedy 2004) and animals [Animal African Trypanosomiasis (AAT) or nagana], and occurs in 37 sub-Saharan countries covering more than 9 million km2, an area which corresponds approximately to one-third of the Africa's total land area. The infection threatens an estimated about 50 million head of cattle. Every year, AAT causes about 3 million deaths in cattle while approximately 35 million doses of trypanocidal drugs are administered. Nagana has a severe impact on agriculture in sub-Saharan Africa (PAAT 2008a; Shaw 2004; Taylor and Authié 2004; Feldmann et al., this volume). There now exists a reasonable collection of methods and reagents from which scientists in well-equipped laboratories may choose the one most appropriate for diagnosis of trypanosomiasis in an given situation (Eisler et al. 2004). See ‘trypanosomosis’.
age structure	Characteristic of a population relating to the age of the individuals in the population. Synonym for age distribution — the distribution of age classes within a population at a particular time; the proportion of individuals of an age class present in a population at any given time (Gordh and Headrick 2001). The proportion of individuals in different age classes of a population at any given time (Pedigo 2002). See ‘population ecology’, ‘population dynamics’, ‘population process’.
aggregation	A group of individuals of one species gathered in one place or small area (Gordh and Headrick 2001). See ‘clumped distribution’.
aggregation pheromone	Chemical compounds synthesized and released by members of a species and which attract members of the same sex or same species to the source of the pheromone (Gordh and Headrick 2001).
air-filtration	Filtration is the process of removing particles from a moving fluid by passage through small openings. In most filtering operations of environmental significance the mechanism is less that of physical straining than of compaction and adsorption onto surfaces of the filter medium (Pfafflin et al. 2008). Filtration of air in an insect rearing facility to remove microbial contaminants and insect diseases, e.g. bacteria, fungi and viruses, and particles, e.g. moth body scales, and hazardous or irritating chemicals that are health hazards to workers. Filters may be coarse, fine (see HEPA) or designed to remove particular chemicals or materials from the air (Dyck 2010, Oborny 1998). See ‘sanitation’.
alkylating agent	A compound causing the substitution of an alkyl group (usually methyl or ethyl) for an active hydrogen atom in an organic compound. Many chemical mutagens are alkylating agents (King et al. 2006). Any of a group of chemical compounds that react with another compound so as to introduce an alkyl group into the second compound (Oxford 2006). See ‘mutagen’.
allele	A shorthand form of allelomorph, one of a series of possible alternative forms of a given gene, differing in DNA sequence, and affecting the functioning of a single product (RNA and/or protein) (King et al. 2006). Any of the forms of the same gene that occur at the same locus on a homologous chromosome but differ in base sequence (Oxford 2006). One of several alternate forms of a gene occupying a given locus on a chromosome or plasmid (Viljoen et al. 2005). One of two or more alternative forms of a gene at a particular locus. If more than two alleles exist, the locus is said to exhibit multiple allelism (Hoy 2003). Form of a gene. Genes are considered allelic when they occur in the same position on members of a chromosome pair (Resh and Cardé 2003). Mutually exclusive form of the same gene, occupying the same locus on homologous chromosomes, and governing the same biochemical and developmental process (NAL 2008). See ‘gene’.
allergy	An immune hypersensitivity response to an agent that is non-antigenic to most of the individuals in a population (King et al. 2006). A state of altered (usually increased) reactivity of the body to foreign material (Oxford 2006). See ‘rearing facility’, ‘occupational health’.
allochthonous	Pertaining to a species with origin in one area but which occurs in other areas (Gordh and Headrick 2001).
allomone	A substance transmitted in chemical communication between individuals of different species that benefits the sender or both the sender and receiver (Daly et al. 1998, Jolivet 1998). A chemical substance, produced or acquired by an organism, which, when it contacts an individual of another species in the natural context, evokes in the receiver a behavioural or physiological reaction adaptively favourable to the emitter (Coppel and Mertins 1977). An allelochemic that induces a response in an individual of another species, e.g. an insect, that is beneficial to the emitting organism. Many allomones are essentially defensive, i.e. toxic or repugnant to potential attackers. However, a scent that attracts bees and therefore facilitates pollination is also an allomone (Maxwell and Jennings 1980). See ‘kairomone’, ‘parapheromone’, ‘pheromone’, ‘synomone’, ‘semiochemical’.
allozyme	Allelic form of an enzyme (Krafsur, this volume). Allelic form of an enzyme that can be distinguished by electrophoresis, as opposed to the more general term isozyme (King et al. 2006). Any enzyme variant produced by a particular allele (Oxford 2006). Allozymes are a subset of isozymes. Allozymes are variants of enzymes representing different allelic alternatives of the same locus (Hoy 2003, King et al. 2006). A particular variant of an enzyme (Resh and Cardé 2003). Alternative enzyme forms encoded by different alleles at the same gene locus (Gordh and Headrick 2001). An allozyme differs in amino acid sequence from other forms of the same enzyme and is encoded by one allele at a single locus (NAL 2008). See ‘genetic marker’, ‘restriction fragment length polymorphism (RFLP)’, ‘randomly amplified polymorphic DNA (RAPD)’, ‘microsatellite’, ‘mitochondrial DNA (mtDNA)’.
all-terrain vehicle (ATV)	A four-wheel vehicle designed for off-road use and travel over rough terrain. Similar to a motorcycle, but the extra wheels make it more stable at slow speeds.
alpha(α)-copaene	A potent attractant for male Mediterranean fruit flies, is found as a minor component in the essential oils of various plant species, including orange, guava and mango. The compound potentially serves as a chemical cue to facilitate orientation of flies to the rendezvous site (Nishida et al. 2000). See ‘parapheromone’.
amplified fragment length polymorphism (AFLP)	The amplified fragment length polymorphism (AFLP) technique demonstrates the presence or absence of restriction sites or fragments in genomic DNA (Krafsur, this volume). The use of the polymerase chain reaction (PCR) to amplify DNA in the study of restriction fragment length polymorphism (Oxford 2006). The variation in the length of DNA fragments produced by the PCR using either one or several specific or arbitrary oligodeoxynucleotide primers and genomic DNA from two or more individuals of a species. AFLPs arise from restriction site polymorphisms, sequence length polymorphisms, and DNA base pair changes not associated with restriction sites. AFLPs are used for example to discriminate between closely related individuals, to localize specific genes in complex genomes (linkage analysis), and to establish genome maps (Kahl 1995).
anaphase	The third phase of mitosis. During anaphase, the block that prevented DNA replication in the centromere region is removed and the centromere becomes functionally double. The chromatids are converted to independent chromosomes that separate and move to opposite poles (King et al. 2006). A stage in mitosis or meiosis during which the two sister chromatids (or homologous chromosomes or daughter chromosomes) of each chromosome separate and move towards opposite poles of the spindle (Oxford 2006, Schlindwein 2006, Lackie and Dow 1995). See ‘mitosis’, ‘meiosis’, ‘prophase’, ‘metaphase’, ‘telophase’, ‘interphase’.
anautogenous	Pertaining to adult insects that require a meal or ingested food before eggs can mature or oviposition can occur (Gordh and Headrick 2001). Antonym = autogenous (Resh and Cardé 2003).
animal traction	Work or draft animals, e.g. oxen, pulling farming implements and equipment for field-preparation, transport, etc. (NAL 2008).
anoxia	A deficiency of oxygen in tissues, blood, or in a body of water (Allaby 1994). Anoxic = Devoid of molecular oxygen; describes the oxygen status of an environment (Resh and Cardé 2003). Severe hypoxia (Webster 2008). See ‘hypoxia’, ‘radiation environment’.
antigen	A chemical compound or substance introduced into the body of an organism and which is recognized as ‘foreign’ of not naturally of that body. Recognition of the foreign substance by the immune system results in the production (release) of antibodies to chemically or physically attack the foreign substance (Gordh and Headrick 2001). A foreign substance that, upon introduction into a vertebrate animal, stimulates the production of homologous antibodies (King et al. 2006). Any molecule that can stimulate an immune response, inducing the production of a specific antibody (MCC 1996).
antimicrobial	Characteristic of a substance or treatment that kills or inhibits micro-organisms (Bijlmakers 2008). Antimicrobial agent = A chemical that kills any or all microbial contaminants (Cohen 2004). Antimicrobial agent = A chemical compound that either destroys or inhibits the growth of microscopic and submicroscopic organisms (MH 1997).
aphrodisiac	Chemical compounds secreted by members of one sex and intended to facilitate copulation after attraction of the opposite sex (Gordh and Headrick 2001).
apparent density	The density of a population that appears to be true according to the sampling method used. Population density is determined by using methods that show proportional changes in population density (Daly et al. 1998). Similar to ‘relative density’. Contrast with ‘absolute density’. Refer to Vreysen (this volume). See ‘absolute density’, ‘Lincoln Index’.
apyrene	Pertaining to spermatozoa that lack a nucleus, and are smaller than normal spermatozoa. Apyrene sperm are a type of spermatozoa produced by Lepidoptera during spermatogenesis, and are the product of meiosis in which chromatin is not normally developed. Apyrene sperm migrate to the spermatheca, but they do not fertilize the eggs. Apyrene spermatozoa bundles disassociate before they reach the duplex region of the male reproductive system. The function of apyrene sperm is not completely understood, but they may facilitate transfer of eupyrene sperm to a female’s copulatory bursa (Gordh and Headrick 2001, King et al. 2006). See ‘eupyrene’, ‘dichotomous spermiogenesis’.
area-freedom	A defined area of land described as free from something, e.g. an insect pest. Area-freedom is a special term implying that an insect pest may have been removed from a given area, but the pest has not necessarily yet been eradicated in the area (Barclay et al., this volume; Hancock et al. 2000).
area-wide	The concept of “area-wide” refers primarily to a total population in a delimited area, the influence of migration/dispersal on its dynamics, and its ecological relationships within its ecosystem (Hendrichs et al. 2007). Area-wide eradication or control refers to eradication or control of a total, discrete, circumscribed population (Leak et al. 2008). See ‘deme’.
area-wide control	A synonym for area-wide integrated pest management. Control measures applied against a given plant pest over a geographically defined area that includes all known or potential hosts with the objective of preventing pest build-up while minimizing damage to commercial host. Control actions are conducted whenever and wherever the target pest exists regardless of host seasonality (Enkerlin 2007). See ‘area-wide’, ‘area-wide integrated pest management’.
area-wide integrated pest management (AW-IPM)	Management of the total pest population within a delimited area (Hendrichs et al. 2007). Integrated pest management against an entire pest population within a delimited geographic area, with a minimum size large enough or protected by a buffer zone so that natural dispersal of the population occurs only within this area (Klassen, this volume). Areawide pest management is a concept of preventive suppression of a mobile insect pest species throughout its geographic range, rather than reactive field-by-field control (USDA 2006). See ‘area-wide’, ‘integrated pest management’.
area-wide sampling	Sampling the total pest population. See ‘area-wide’, ‘sampling’.
artificial diet	Food that has been synthesized from one or more ingredients that may be completely defined chemically or that may be partially defined or not defined. An artificial diet and a synthetic diet are essentially synonymous (Cohen 2004). An unfamiliar food which has been formulated, synthesized, processed, and/or concocted by man, on which an insect in captivity can develop through all or part of its life cycle (Singh 1977).
aspermic	Inability of males to produce sperm (Klassen, this volume).
assessment	Evaluation or estimation of the value, importance or quality of something (Oxford 2001), e.g. quality of reared insects, achievement of pest management goals, economic benefits.
assortative mating	A tendency for male/female of a given population to preferably mate with male/female of the same population (FAO/IAEA/USDA 2003). Sexual reproduction in which the pairing of male and female is not random, but involves a tendency for males of a particular kind to breed with females of a particular kind. If the two parents of each pair tend to be more (less) alike than is to be expected by chance, then positive (negative) assortative mating is occurring (King et al. 2006). Preference for mating between similar individuals (Schlindwein 2006). A mating system in which conspecific sexes of a reproducing population tend to mate based on similarity of some measurable parameter such as overall body size, e.g. small males tend to mate with small females and large males mate with large females (Gordh and Headrick 2001). Non-random selection of mates with respect to one or more traits (Ayala and Kiger 1984). See ‘isolation index (ISI)’, ‘relative isolation index (RII)’, ‘female relative performance index (FRPI)’, ‘male relative performance index (MRPI)’.
attract and kill	Method of pest control – selectively attracting a pest insect to a source using a chemical attractant, e.g. sex pheromone, and then killing the insect with an insecticide (APTIV 2007). See ‘live-bait technology’, ‘stationary-bait technology’, ‘lure and kill’.
attraction	Act or power of attracting (Collin 2001). Response of an insect in noticing, responding to or orienting/moving towards an object or chemical that is attractive to the insect. An attractant is a chemical or visual stimulus that results in movement of a pest towards the source (IAEA 2003).
attractive device	Device that is attractive to an insect, or contains an attractant, e.g. sex pheromone trap, object with a particular colour and/or shape, chemical-impregnated lure, light trap, etc. that attracts an insect. See ‘delta trap’, ‘Jackson trap’, ‘pheromone trap’, ‘sticky trap’, ‘trap’, ‘wing trap’.
attribute	A characteristic quality (Oxford 2001). A quality, trait, characteristic or feature of an organism. Attributes may be biochemical, behavioural, ultrastructural or anatomical (Gordh and Headrick 2001).
augmentative biological control	A strategy for pest management involving the mass propagation and organized release of beneficial natural enemies for the regulation of a pest population (Gordh and Headrick 2001). Biological control designed to increase the number or effectiveness of existing natural enemies (Pedigo 2002).
autocidal	Causing death to itself or to its own species. Autocidal control is the use of an insect species against itself, usually through some means of genetic modification, to suppress or eradicate its natural population (Coppel and Mertins 1977), or the use of insects to control wild-type populations of the same species (Resh and Cardé 2003).
autoconfusion	A type of mating disruption particularly suited for moth pests, in which released sterile males would carry on their bodies pheromone particles that attract wild males. This would transfer particles to them, and subsequently these males would contaminate other males, resulting in increased mating disruption (Robinson and Hendrichs, this volume).
autodissemination	Sterile insects are inoculated with electrostatically charged powder formulated with entomopathogens or slow-acting insecticides, which would be spread throughout the pest population through intraspecific interactions (Robinson and Hendrichs, this volume).
automation	The use of automatic equipment instead of manual labour (Oxford 2001).
autosome	Any chromosome other than a sex chromosome (King et al. 2006).
autosterilization	After being attracted into a trap, wild insects sterilize themselves by contacting a chemosterilant and then escape the trap. Another method is to transfer a chemosterilant from one (treated) insect to another during mating (Klassen, and Nagel and Peveling, and Robinson and Hendrichs, this volume).
backcross	A cross between an offspring and one of its parents or an individual genetically identical to one of its parents (King et al. 2006).
backcross sterility	Sterility in insects resulting from backcrossing (example tobacco budworm, Bloem et al., this volume).
bait	A pesticide formulation that combines an edible and/or attractive substance with a pesticide, e.g. grasshopper bait (Pedigo 2002, Gordh and Headrick 2001). For tsetse fly baits, refer to Van den Bossche and De Deken (2004); for fruit fly baits, refer to Nigg et al. (2004). A lure intended to attract specific organisms (Gordh and Headrick 2001).
bait spray	Bait sprayed as a liquid, e.g. bait spray for fruit flies. Refer to Mangan (this volume), Nagel and Peveling (this volume), Nigg et al. (2004). See ‘bait’, ‘feeding stimulant’.
baseline data	Data about the beginning or original condition, e.g. insect population density, and are used to compare with data obtained subsequently. Refer to Vreysen (this volume), Everitt (2006) and Leak et al. (2008).
bednet	Fine-mesh netting (may be impregnated with an insecticide) hung over a bed to protect a sleeping person from being bitten by an insect such as a mosquito. Refer to WHO (2004).
beef losses	Economic loss from death of beef cattle [due to insect pests] (Barclay, this volume).
behavioural ecology	The study of movements and activities of animals as they relate to interrelations with other organisms and the environment (Resh and Cardé 2003).
behavioural resistance	The ability of an insect population to change its behaviour to avoid insecticides or other detrimental circumstances (Gordh and Headrick 2001). The ability of an insect population to change its behaviour in order to avoid insecticides or other injurious factors (Pedigo 2002).
beneficial species	Any organism directly or indirectly advantageous to plants or plant products, including biological control agents (FAO2006). An organism (pathogen, predator, parasite) that helps reduce a pest population (Gordh and Headrick 2001). An organism that is used in the biological control of pests, weeds or diseases, usually as part of an integrated pest management strategy (Coombs and Hall 1998).
beneficiary	A person who benefits from something (Oxford 2001, 1993). The person who receives or is to receive the benefits resulting from certain acts (Friedman 2007).
benefit/cost analysis (BCA)	Calculation and analysis of the benefits and costs of a project by an appropriate comparison, such as the benefit/cost ratio. The benefit/cost ratio seeks to compare the benefits of a particular action with its cost. For example, a benefit/cost ratio of 2:1 implies that the economic benefit is twice that of the cost. Sometimes it is difficult to quantify the benefits (Porteous 1996). Benefit/cost (or cost/benefit) analysis is a method of measuring the benefits expected from a decision, calculating the cost of the decision, then determining whether the benefits outweigh the costs. This analysis determines whether programmes are achieving their goals or proposed programmes are worthwhile (Friedman 2007, Oxford 1993). It considers all gains (benefits) and losses (costs) regardless of to whom they accrue (Pearce 1992). In terms of human health, Everitt (2006) defines cost/benefit analysis as a technique where health benefits are valued in monetary units to facilitate comparison between different programmes of health care. The main practical problem with this approach is getting agreement in estimating money values for health outcomes. Similar problems occur with environmental and other social benefits, which can be difficult to consistently translate into monetary values. Statt (1991) defines cost/benefit analysis as a technique for comparing all the costs (both tangible and intangible) of a particular course of action with resulting benefits expected. It normally therefore includes social or environmental costs as well as financial ones. Major issues in benefit/cost analysis include: identifying all benefits and costs applicable to the project, establishing consistent units of comparison (usually monetary), identifying opportunity costs of practical alternative investments for comparisons, determining a reasonable time horizon for the analysis (uncertainty increases as the horizon lengthens), choosing an appropriate discount rate, accounting for risk or uncertainty in estimates over time, and choosing the objectives against which project performance is to be measured. Refer to Mumford (this volume).
bent wing	A disabling wing mutation in females of a laboratory-reared strain of the Queensland fruit fly (Franz, this volume). Deformed wings are the wings of flies that are not fully expanded or are bent or crumpled (FAO/IAEA/USDA 2003).
bifurcation	Division into two branches or forks (Barclay, this volume; Oxford 2001, Leak et al. 2008).
binomial distribution	A theoretical distribution of the number of successes in a finite set of independent trials with a constant probability of success. In probability theory and statistics, the binomial distribution is the discrete probability distribution of the number of successes in a sequence of n independent yes/no experiments, each of which yields success with probability p (Wikipedia 2008). A discrete frequency distribution which, when a chance event has only two possible outcomes, often termed "success" and "failure", each with fixed probabilities of occurring, gives the probabilities of the number of successes in a given number of independent trials of the event (Webster 2008, Everitt 2006, Clapham 1996, FAO/IAEA 1973). See ‘Poisson distribution’, ‘Poisson binomial distribution’, ‘negative binomial distribution’, ‘hypergeometric probability distribution’, ‘probability model’.
bioassay	Test of a substance by examining the effect it has on living organisms (Collin 2001). A method of measuring the effects of a biologically active substance using a living organism in vivo or in vitro tissue or cell model under controlled conditions (NAL 2008). The quantitative measurement, under standardized conditions, of the effects of a substance on an organism or part of an organism (Allaby 1994). Measurement of the effect on an organism of a given stress, such as a toxic substance, heat, cold, or drought (Maxwell and Jennings 1980). Bioassay (biological assay) is the measurement of a biological response, e.g. mortality, to different concentrations of a biologically active compound, using standardized conditions in the laboratory or field (Resh and Cardé 2003). A method for determining the concentration of a substance by measuring its effect on a living system under controlled conditions. Bioassays can be used to measure the relative potency of a substance by comparing the effect it causes with that caused by a substance of known potency (Coombs and Hall 1998).
biodiversity	Biodiversity (biological diversity) is the variation in all living organisms from gene to ecosystems (Resh and Cardé 2003). The condition of being different (diverse) biologically. The variety of the world’s organisms, including their genetic diversity and the assemblages they form. A ‘blanket’ term for the natural biological wealth on the earth. The variety of living organisms considered at all levels, from genetics through species, to higher taxonomic levels, and including the variety of habitats and ecosystems. The variety and variability among living organisms and the ecological complexes in which they occur (Gordh and Headrick 2001). Richness of the number of species (Collin 2001). Diversity of plant and animal species in an environment (MCC 1996). All aspects of biological diversity, but especially species richness, the complexity of ecosystems, and genetic variation (Allaby 1994). See ‘diversity’.
biological control	Pest control strategy making use of living natural enemies, antagonists, competitors or other biological control agents. A biological control agent is a natural enemy, antagonist or competitor, or other organism, used for pest control (FAO 2006). The use of living organisms, parasitoids, predators, pathogens, and competitors to suppress pest populations below levels that would occur naturally. Biological control programmes are intended to suppress invasive species through importation of specialized natural enemies that have evolved with a pest in its native range (Resh and Cardé 2003). The employment of any biological agent for control of a pest (Pedigo 2002). The control of pests by employing natural enemies including predators, parasites and pathogens. The use of natural enemies such as parasitoids, predators, pathogens, antagonist, or competitor populations to suppress a pest population making it less abundant and thus less damaging (Gordh and Headrick 2001). The use of predatory and parasitic insect species (termed natural enemies or beneficials), or natural products consisting of or derived from micro-organisms, against pests and diseases of crops (Coombs and Hall 1998). Also, biological insect pest suppression is defined as the use or encouragement, by man, of living organisms or their products for the population reduction of pest insects (Coppel and Mertins 1977). Classical biological control is the intentional introduction and permanent establishment of an exotic biological agent for long-term pest control (FAO 2006, FAO/IAEA/USDA 2003). Classical biological control is the importation of foreign natural enemies to control previously introduced, or native, pests (Weeden et al. 2000). Biological pest suppression in its narrow, classical sense, usually restricted to the introduction, by man, of parasitoids, predators, and/or pathogenic micro-organisms to suppress populations of plant or animal pests (Coppel and Mertins 1977). See ‘natural enemies’, ‘integrated pest management (IPM)’.
biological radiation effects	The effects of radiation on biological processes, structures and functions; some effects are positive and many are negative. Refer to Bakri et al. (this volume). See ‘radiation biology’.
biomass	The total dry weight or volume of all living organisms in a given area (Pedigo 2002). The collective organic matter that results from the photosynthetic conversion of solar energy (Gordh and Headrick 2001). Total weight of living organisms at any one time per unit area (Jolivet 1998). Weight of plant or animal material produced in an area, both as standing biomass and harvested biomass (Hill 1997). The mass of living organisms forming a prescribed population in a given area of the earth’s surface. It is usually expressed in grams per square metre (g/m2) (Porteous 1996).
biosafety	Prevention of large-scale loss of biological integrity, focusing on both ecology and human health (Webster 2008). Human safety in dealing with biological materials, e.g. eating certain foods that may be regarded as unsafe to eat. See ‘genetically modified organism (GMO)’, ‘food safety’.
biosecurity	Assurance that ecologies sustaining either people or animals are maintained. This may include natural habitats as well as shelter and productive enterprises (especially agriculture), and deals with threats such as biological warfare or epidemics. This is related to the more passive concept of ‘biosafety’ (Webster 2008). A component of biosecurity is to protect biodiversity and manage risks to plant and animal health and animal welfare (Webster 2008). See ‘food security’.
biota	The fauna and flora of a given habitat, area or zoogeographical region (Gordh and Headrick 2001).
bio-terrorism	Bio-terrorism is terrorism using germ warfare, an intentional human release of a naturally occurring or human-modified toxin or biological agent (Webster 2008). The use of biological agents, such as agricultural pathogens of pests, for terrorist purposes (NAL 2008).
birth control	In human biology, birth control refers to the use of contraception to prevent unwanted pregnancies (Oxford 2001). Birth control is also achieved through reproductive sterilization. By releasing sterile males into a fertile insect population, the sterile insect technique (SIT) acts as a form of birth control imposed on an insect pest population to reduce its numbers (Klassen, this volume).
birth rate	The ratio between the number of live births and a specified number of individuals in a population over a given period of time (MH 1997). Natality is the rate of birth, often measured as the total number of eggs or eggs per female per unit of time (Pedigo 2002). See ‘mortality’.
bisexual SIT	Bisexual (both males and females) release of sterile insects is probably less effective than male-only release in introducing sterility into the target wild population. In bisexual release, the sterile males tend to mate with sterile females instead of fertile wild females; the number of sterile females is much larger than that of fertile females. Also, for some insect species, releasing sterile females causes damage; for example, sexually sterile fruit fly females sting fruit with their ovipositor (Klassen and Curtis, Calkins and Parker, Franz; this volume).
bivalents	Homologous, synapsed chromosomes (King et al. 2006, Lackie and Dow 1995). During the prophase of meiosis I, homologous chromosomes pair and form synapses. The paired chromosomes are called bivalents. The bivalent has two chromosomes and four chromatids, with one chromosome coming from each parent (Schlindwein 2006). The figure produced by pairing of homologous chromosomes at the beginning of meiosis (Burt and Trivers 2006). The structure containing all four chromatids (two representing each homologue) at the start of meiosis (Lewin 1985). Two homologous chromosomes that pair during the first meiotic division (Ayala and Kiger 1984).
border	Boundary line or area separating countries, states, regions, places, etc. Line demarcating the edge of a thing or an area of activity, e.g. treatment for pest control.
bottleneck	In the context of genetics and insect rearing: the bottleneck effect is the occurrence of fluctuations in gene frequencies when a large population passes through a contracted stage and then expands again with an altered gene pool (usually one with reduced variability) as a consequence of genetic drift (King et al. 2006). A period when a population becomes reduced to only a few individuals (Ayala and Kiger 1984). Change in gene frequencies and decline in total genetic variation where there is a sharp decrease in population numbers (Collin 2001). In general terms, a bottleneck in a technical process is a restriction or blockage that prevents achieving fully the goal of the process.
Bremsstrahlung	Electromagnetic radiation generated when electrically charged particles are accelerated or decelerated. The spectrum of emitted radiation reaches from a maximum energy given by the kinetic energy of the generating particle down to zero energy. Bremsstrahlung only becomes easily noticeable when the energy of the particle is very high compared to its self-energy. This is mostly only valid for electrons (self-energy of the electron: 511 keV) (Koelzer 2008). Broad-spectrum electromagnetic radiation emitted when an energetic electron is influenced by strong electric field, such as that in the vicinity of an atomic nucleus. Particularly, Bremsstrahlung is produced when an electron beam strikes any material (converter). The Bremsstrahlung spectrum depends on the electron energy, the converter material and its thickness, and contains energies up to the maximum kinetic energy of the incident electrons (ISO/ASTM 2002). Electromagnetic radiation emitted (as photons) when a fast-moving charged particle (usually an electron) loses energy upon being accelerated and deflected by an electric field surrounding a positively charged nucleus. X-rays produced in ordinary X-ray machines are Bremsstrahlung. ‘Bremsstrahlung’ is a German word meaning ‘braking radiation’ (Borders 1991, Isaacs 2000). The photon radiation emitted by fast-moving charged particles that are sharply decelerated or deflected by an electric or magnetic field (IAEA 1992).
bridge formation	The primary lesion leading to a dominant lethal mutation is a break in the chromosome. When a break is induced in a chromosome in mature sperm, it remains in this condition until after the sperm has entered an egg. Following fusion, nuclear divisions begin, and a break in a chromosome can have drastic effects on the viability of the embryo as development proceeds. During early prophase the broken chromosome undergoes normal replication, but during metaphase the broken ends can fuse leading to the formation of a dicentric chromosome and an acentric fragment. The acentric fragment is frequently lost, while the dicentric fragment forms a bridge at anaphase leading to another chromosomal break. This whole process then repeats itself, leading to the accumulation of serious imbalances in the genetic information of the daughter cells. The accumulation of this genetic damage finally leads to the death of the zygote. If two different chromosomes are broken they can also rejoin. These chromosomes produce the same problems for the dividing cells as those formed by a break in a single chromosome, by undergoing incorrect fusion and leading to the breakage-fusion-bridge cycle. In this way dominant lethal mutations can cause cell death, and the accumulation of genetic imbalance in the developing zygote leads to lethality (Robinson, this volume).
broad-spectrum insecticide	Insecticide that affects pests and beneficial organisms (Gordh and Headrick 2001). Insecticide that is active against a wide range of pests, killing insects indiscriminately, including beneficial organisms; thus it may cause outbreaks of other pests such as mites (Coombs and Hall 1998).
Brownian random motion	‘Brownian movement’ refers to the peculiar random movements shown by microscopic particles in a disperse phase, i.e. when suspended in a liquid or gas. It is caused by the continuous irregular bombardment by the molecules of the surrounding medium (Oxford 2006). The rate of Brownian random motion is invariant in time and space (Itô and Yamamura, this volume). See ‘stochastic model’.
Bt	Short form of the bacterium Bacillus thuringiensis Berliner. A bacterium used as a biopesticide in the control of numerous chewing-insect pests, particularly Lepidoptera larvae with alkaline pH in gut. It must be ingested to be effective, and acts as a stomach poison. It is probably the most popular naturally derived product used for insect pest control (Gordh and Headrick 2001).
Bt kurstaki	Bacterium Bacillus thuringiensis Berliner variety kurstaki.
Bt-cotton	A transgenic variety of the cotton plant developed to have resistance to lepidopterous pests. Bt genes responsible for endotoxin have been incorporated into the cotton genome (Gordh and Headrick 2001). See ‘transgenic cotton’, ‘transgenesis’.
Btk	Short form of the bacterium Bacillus thuringiensis Berliner variety kurstaki.
buffer zone [barrier]	An area in which a specific pest does not occur or occurs at a low level and is officially controlled, that either encloses or is adjacent to an infested area, an infested place of production, an area of low pest prevalence, a pest free area, a pest free place of production, or a pest free production site, and in which phytosanitary measures are taken to prevent spread of the pest (FAO 2006). An area separating two or more types of land use (Webster 2008). Land between a protected area, e.g. a nature reserve, and the surrounding countryside or town (Collin 2001). See ‘temporary buffer zone’, ‘permanent buffer zone’.
business plan	A business plan is a summary of how a business owner, manager, or entrepreneur intends to organize a commercial endeavour and implement activities necessary and sufficient for the venture to succeed. It is a written explanation of the companies business model. Business plans are used internally for management and planning, and are also used to convince outsiders, such as banks or venture capitalists, to invest money into a venture. A business plan can be seen as a collection of sub-plans including a marketing plan, financial plan, production plan, and human resource plan. (Webster 2008). A business plan is needed to organize and conduct an operational AW-IPM programme that includes the rearing of insects and an SIT component (IAEA 2008a).
canister	A durable, reusable container, usually an aluminium or steel cylinder, used to hold a product, e.g. factory-reared insects in packaging containers, during the radiation process (ISO/ASTM 2004a). Canisters are not used in some applications in which the packaging container is sufficiently rigid and the design of the irradiator is appropriate.
cannibalism	A behavioural phenomenon in which an insect feeds upon members of the same species. Some insects feed cannibalistically when under conditions of starvation, and some insects are cannibalistic as a part of their lifestyle (Gordh and Headrick 2001).
carcinogenic	Capable of causing or producing cancer (Oxford 2001, Borders 1991). A carcinogen is a physical or chemical agent that induces cancer. A carcinogen is usually mutagenic, and it either damages nucleic acids directly or indirectly, or it causes a genetic imbalance by inducing a chromosomal aberration (King et al. 2006).
carrying capacity	The maximum population density a given environment will support for a sustained period (Pedigo 2002, Gordh and Headrick 2001). The maximum population size or density of a species that can be sustained indefinitely in a given environment (Resh and Cardé 2003). The maximum population that may be sustained in an ecosystem or management unit without adverse effects to the environment (NAL 2008).
cash flow	The total amount of money passing into and out of a business, especially as affecting liquidity (Oxford 2008, Statt 1991). The excess of cash revenues over cash outlays in a given period of time (Webster 2008). Analysis of all the changes that affect the cash account during an accounting period (Friedman 2007). The amount of cash being received and expended by a business, which is often analysed into its various components (Oxford 1993).
census	A count or survey of a population (Oxford 2001).
centralized facility	A single centralized insect rearing facility where all of the major activities related to sterile insect production are conducted — mass-rearing and sterilization of insects, and preparation of the sterilized insects for release. Compare this with the use of satellite facilities (Dowell et al., this volume). See ‘satellite facility’, ‘rearing facility’, ‘mass-rearing facility’, ‘modular rearing facility’.
centromere	A region of a chromosome to which spindle traction fibres attach during mitosis and meiosis (King et al. 2006, Oxford 2006, Schlindwein 2006, Hoy 2003). In some insects, the spindle fibres attach throughout the length of the chromosome, and such chromosomes are called holocentric (Schlindwein 2006, Hoy 2003). See ‘acentric’, ‘dicentric’, ‘monocentric’, ‘holokinetic’, ‘monokinetic’.
ceralure	A synthetic lure to attract male Mediterranean fruit flies (Warthen et al. 1998, IAEA 2003, NAL 2008). See ‘cuelure’, ‘disparlure’, ‘gossyplure’, ‘hexalure’, ‘propylure’, ‘swormlure’, ‘trimedlure’.
certified organic	Description or label of agricultural products produced by organic methods and certified as organic by a designated organization. A common feature of organic agriculture is that crops are produced without using synthetic pesticides (Gordh and Headrick 2001).
Chagas’ disease	A disease of vertebrates, including humans, in Latin America caused by a parasite Trypanosoma cruzi Chagas. The disease is transmitted among mammals via the excrement of biting bugs (Triatoma spp., Reduviidae) (Gordh and Headrick 2001, TDR 2008, Lopes and Chapadeiro 2004).
chemical communication	Communication among insects using chemicals (smell, taste). Refer to Wyatt (2003). Communication is the production of a signal by an individual that influences the behaviour of another individual and that is mutually beneficial (Auburn 2008). See ‘contact pheromone’, ‘pheromone’.
chemical control	A principal approach or pest management strategy that involves the use of pesticides or toxic chemicals to suppress pest populations (Gordh and Headrick 2001, Schmutterer 1969). Pest management practices which rely upon the application of synthetic or naturally-derived pesticides (Weeden et al. 2000). The control of pests with synthetic pesticides (Bijlmakers 2008).
chemical mutagen	See ‘mutagen’.
chemosterilization	Reproductive sterilization of an animal using chemosterilants — chemicals that induce reproductive sterility (Pedigo 2002; Jolivet 1998; Hill 1997, 1975).
chiasmata	Chiasma (plural chiasmata) is the cytological manifestation of crossing-over; the cross-shaped points of junction between non-sister chromatids (King et al. 2006). A connection formed between chromatids, visible during meiosis, thought to be the point of the interchange involved in crossing-over (Oxford 2006, Schlindwein 2006). Chiasmata occur during prophase I of meiosis and represent points where crossing-over, or exchange of genetic information, between non-sister chromatics occurred. When the synapsed chromosomes begin to separate in late prophase I, they are held together by these connections between the chromatids of homologous chromosomes (Hoy 2003). See ‘crossing-over’, ‘pachytene’, ‘meiosis’.
chilling	Reducing the temperature of insects, usually to just above 0ºC, to immobilize them during handling, transport or storage. An extended period of chilling may be harmful to insects. To immobilize insects, chilling is often more convenient than CO2 anaesthetization. See ‘cold storage’.
chitin	A nitrogenous polysaccharide occurring in the cuticle of arthropods and certain other invertebrates (Resh and Cardé 2003, Gordh and Headrick 2001, Borror et al. 1989, Pfadt 1962). The major component of arthropod cuticle, a polysaccharide composed of acetyl-glucosamine and glucosamine sub-units (Pedigo 2002, Wall and Shearer 1997). The main biopolymer in insect cuticle, consisting of a β-pleated polysaccharide sheet (Grimaldi and Engel 2005).
chitin synthesis inhibitor	An insect growth regulator that inhibits production of chitin in the integument of insects and other arthropods (Gordh and Headrick 2001). An insecticide that prevents chitin formation (Wall and Shearer 1997). Insecticide that interferes with cuticle development and moulting (Daly et al. 1998). See ‘insect growth regulator (IGR)’, ‘juvenile hormone (JH)’.
chromatids	The two daughter strands of a duplicated chromosome that are joined by a single centromere. Upon the division of the centromere, the sister chromatids become separate chromosomes (King et al. 2006, Oxford 2006, Schlindwein 2006, Burt and Trivers 2006, Hoy 2003). See ‘meiosis’, ‘crossing-over’, ‘pachytene’.
chromatin	The complex of nucleic acids (DNA and RNA) and proteins (histones and non-histones) comprising eukaryotic chromosomes (King et al. 2006, Schlindwein 2006). It stains strongly with basic dyes (Oxford 2006).
chromosomal aberration	An abnormal chromosomal complement resulting from the loss, duplication, or rearrangement of genetic material (King et al. 2006). See ‘aberration’.
chromosomal inversion	Chromosome segments that have been turned through 180º with the result that the gene sequence for the segment is reversed with respect to that of the rest of the chromosome. Inversions may include or exclude the centromere. An inversion that includes the centromere is called pericentric, whereas an inversion that excludes the centromere is called paracentric (King et al. 2006, Burt and Trivers 2006). Alteration of the sequence of a DNA molecule by removal of a segment followed by its reinsertion in the opposite orientation. Inversions create changes in gene order, and sometimes cause disordered meiosis, genetic abnormalities, and reduced fertility (Hoy 2003, Oxford 2006). In an inversion heterozygote one of the chromosomes contributed by one parent has an inverted segment while the homologous chromosome contributed by the other parent has the normal gene sequence (Schlindwein 2006, Burt and Trivers 2006). Refer to Franz (this volume). See ‘pericentric inversion’, ‘paracentric inversion’.
chromosomal polymorphism	The presence in the same interbreeding population of one or more chromosomes in two or more alternative structural forms (King et al. 2006). The existence within a population of two or more different structural arrangements of chromosomal material (King et al. 2006, Ayala and Kiger 1984).
chromosomal rearrangement	A chromosomal aberration involving new juxtapositions of chromosomal segments (King et al. 2006). Any change in the normal order of genes on a chromosome, caused by inversions or translocations (Kahl 1995).
chromosomal translocation	The exchange of segments of non-homologous chromosomes. Translocations are apparent when the chromosome number is correct, but two chromosomes have abnormal sizes and banding patterns. Some are associated with malignancy (Oxford 2006). Transfer of a segment of a chromosome to a non-homologous chromosome. Translocations are usually reciprocal (Schlindwein 2006, Kahl 1995). Change in location of a chromosome segment by becoming attached to another chromosome (Burt and Trivers 2006). A type of mutation in which a section of a chromosome breaks off and moves to a new position in that or a different chromosome (Hoy 2003). The fusion of part of one chromosome on to part of another (Lackie and Dow 1995, NAL 2008).
chromosome	In the eukaryotic nucleus, one of the threadlike structures consisting of chromatin and carrying genetic information arranged in a linear sequence; in prokaryotes, the circular DNA molecule containing the entire set of genetic instructions essential for life of the cell (King et al. 2006, Schlindwein 2006, Kahl 1995). A structure composed of a very long molecule of DNA and associated proteins, e.g. histones, that carries hereditary information. The number of chromosomes is characteristic for the species concerned (Oxford 2006). Units of the genome with many genes (Hoy 2003, Burt and Trivers 2006, Pedigo 2002).
citrus canker	Disease of citrus trees caused by a bacterium, usually having lesions on the leaves, stems and fruit, with localized patches of dead tissue surrounded by swollen margins (Wikipedia 2008, Gordh and Headrick 2001, IDIDAS 2008).
citrus peel oil	Oil from citrus peel has been found to affect the mating behaviour of fruit flies. See ’aromatherapy’.
civil unrest	Civil unrest, or civil disorder, is a condition in the society where people, due to discontent over some issue, are engaged in several forms of disturbance such as parades, sit-ins, riots, sabotage and other forms of crime. It is intended to be a demonstration to the public and the politics but can be easily evolved to chaos (Webster 2008).
clumped distribution	The distribution of individuals (manner in which they are spread out over an area) may be described as uniform, random or clumped. In a clumped distribution, individuals are found in groups which are separated and distinct from other groups, i.e. a patchy distribution (Wikipedia 2008). Refer to Vreysen (this volume). See ‘distribution’, ‘homogeneous distribution’, ‘continuous distribution’, ‘fragmented distribution’, ‘island distribution’.
Code of Conduct	In general, a ‘code of conduct’ is a description of acceptable behaviour in relation to a specific activity or procedure. Sometimes governments agree on a code of conduct regarding trade practices and procedures. Regarding the import and release of biological control agents, a regulatory framework has been provided by the International Plant Protection Convention (IPPC) in the form of International Standard for Phytosanitary Measures (ISPM) Number 3 “Code of Conduct for the Import and Release of Exotic Biological Control Agents” (FAO 1996a; Robinson and Hendrichs, this volume). There is also an International Code of Conduct on the distribution and use of pesticides (FAO 2003).
Code of Practice	The rules and documented procedures established by regulatory bodies or trade associations which serve as a guide to acceptable practices. They do not have the force of law (NAL 2008).
cold storage	Storage of materials at a cold temperature using refrigeration, usually close to 0ºC. See ‘chilling’ and ‘cryopreservation’.
cold tolerance	Ability to withstand for a period of time the effects of exposure to cold temperatures and suffer no or little biological damage. Some animals and plants are more cold tolerant than others (Kimura 2004; Parker, this volume).
colonization	The act of colonizing or state of being colonized (Gordh and Headrick 2001); to start a new colony of insects in a laboratory using wild insects collected in the field. In biological control, the release of natural enemies into an area for the control of pests (Gordh and Headrick 2001). In ecology/evolutionary biology, often refers to the infiltration of a parasite onto new host species; in biogeography, to infiltrate new territory and establish breeding populations (Grimaldi and Engel 2005). See ‘domestication’, ‘strain domestication’, ‘selection’.
colony	Individuals of one species living in close association in space and time (Gordh and Headrick 2001). For insect mass-rearing, a colony of a species consists of all stages of the insect kept in a rearing facility. For social insects, a colony is a group of individuals that cooperatively construct nests or rear offspring (Gordh and Headrick 2001).
colony contamination	Presence in an insect colony of individuals that are undesirable for genetic or other reasons.
commercialization	In the context of rearing insects or operating area-wide pest management programmes, producing and managing insects for a profit, usually by a private company (IAEA 2008a; Dyck, Flores et al., this volume).
commission	In the context of the SIT and AW-IPM, an organization established to manage, finance, and operate a pest management programme. Even though somewhat similar to a government, a commission has the advantage of being independent of normal government bureaucratic procedures and therefore is able to respond quickly and efficiently in dealing with programme requirements (Dyck, Flores et al., this volume). See ‘operational independence’.
compatibility	Ability to exist or be used together without conflict, well suited to each other (Oxford 2001). Ability of two organisms to live together in a balanced relationship, e.g. host and parasite; also applies to a mixture of chemicals in a pesticide spray (Hill 1997, Bijlmakers 2008). In the context of sexual compatibility, the level of anatomical and especially behavioural similarity that permits mating between individuals of different origins, e.g. different insect strains of different geographical origins. Mating tests in a field cage or laboratory can measure sexual compatibility. Mating compatibility means that females of a given strain are able and willing to accept, for mating, the males of another strain; this also includes synchrony and other factors that cause reproductive disconformancy (FAO/IAEA/USDA 2003). Refer to Lance and McInnis (this volume). See ‘mating compatibility’, ‘mating barrier’.
competitiveness	Ability of an organism to compete with conspecific organisms for a limited environmental resource (FAO/IAEA/USDA 2003). The level of ability to compete with others (physical struggle or indirect interaction) for the same object, place or goal. The interaction among individuals for a common resource. Competition can be intraspecific or interspecific (Gordh and Headrick 2001). Competition occurs when two or more organisms, or populations, interfere with or inhibit one another as they strive to secure a resource that is in limited supply (Bijlmakers 2008, FAO/IAEA/USDA 2003). Interaction between two or more organisms or species that utilize the same resources, in which the presence of one reduces the birth rate or increases the death rate of the other (Resh and Cardé 2003). In the SIT, reared sterile males compete against wild males to mate with wild females. See ‘mating competitiveness’, ‘Haisch Index’.
conditional lethal mutation	A mutation that may be lethal only under certain environmental conditions (Hoy 2003). Any mutation that produces a mutant whose viability depends on the conditions of growth. It grows normally in permissive conditions but in restrictive conditions it does not grow, thereby expressing its lethal mutation, e.g. temperature-sensitive mutation (Oxford 2006, Watson 1976). A mutation that exhibits wild phenotype under permissive environmental conditions, but exhibits a mutant phenotype under restrictive conditions. For example, some bacterial mutants are conditional lethals that cannot grow above 45ºC, but grow well at 37ºC (King et al. 2006, Fenner et al. 1987, Lewin 1985, Ayala and Kiger 1984). See ‘temperature-sensitive lethal (tsl)’.
conditional probability	The probability that an event occurs given the outcome of some other event; usually written, Pr(A\|B) (Everitt 2006). For two events A and B, the probability that A occurs, given that B has occurred, is denoted by Pr(A\|B), read as ‘the probability of A given B’ (Clapham 1996).
confidence limits	The endpoints of the interval about the sample statistic that is believed, with a specified confidence coefficient, to include the population parameter (ASQC 1996). A confidence interval is an interval, calculated from a sample, which contains the value of a certain population parameter with a specified probability. The end-points of the interval are the confidence limits. The specified probability is called the confidence level. An arbitrary but commonly used confidence level is 95%, which means that there is a one-in-twenty chance that the interval does not contain the true value of the parameter (Clapham 1996). A confidence interval is a range of values, calculated from the sample observations, that is believed, with a particular probability, to contain the true parameter value (Everitt 2006).
conservation	Avoiding waste of, and renewing when possible, human and natural resources; the protection, improvement, and use of natural resources according to principles that will assure their highest economic or social benefits (USDA 1993). Preservation of natural habitats, and protection of natural resources with a view to sustained yield (Hill 1997). In biological control, any practice designed to protect and maintain populations of existing natural enemies (Pedigo 2002, Weeden et al. 2000, Daly et al. 1998).
conspecific	Belonging to the same species (Jolivet 1998, Earthlife 2008). Individuals, populations or subspecies that are assigned to one nominal species or belong to the same species (Gordh and Headrick 2001).
constraint	A limitation or restriction (Oxford 2001). Refer to Whitten and Mahon (this volume).
contact pheromone	A pheromone communicated by contact with antennae (contact chemoreception), involves cuticular hydrocarbons, and may be a component of mate recognition and other behaviour such as aggregation (Schulz and Ando 2004, Wyatt 2003, Cardé and Minks 1997, Siljander et al. 2007, Ginzel and Hanks 2003, Ginzel et al. 2003, Hammack 1992). See ‘pheromone’, ‘cuticular hydrocarbon’.
containerized rearing system	To avoid cannibalism, rearing individual insects in containers, e.g. cups, cells, etc. that isolate insects from each other. Rearing insects in relocatable containers (each container being a small laboratory) which can be moved to a new site if desired.
containment	Application of phytosanitary measures in and around an infested area to prevent spread of a pest (FAO 2006; IAEA 2003; Hendrichs et al., this volume). The prevention of the spread of an organism or substance beyond a defined boundary (Coombs and Hall 1998). A type of regulatory-control programme in which a target pest is confined within a geographical region. The concept of containment is applied in a legal sense against pests established in the area of concern and for which eradication is not practical or applicable. Typically, containment does not attempt to reduce or eliminate the pest population in the area of infestation (Gordh and Headrick 2001). Refer to Hendrichs et al.(section 2.3.) (this volume). See ‘prevention’, ‘exclusion’, ‘pest free area’, ‘invasive species’, ‘strategic option’.
contamination	Presence in a commodity, storage place, conveyance or container, of pests or other regulated articles, not constituting an infestation (FAO 2006). A contaminant is an undesired physical, chemical, biological, or radiological substance that can have an adverse effect on air, water, soil, etc. (USDA 1993). The deposition of unwanted radioactive material on the surfaces of structures, areas, objects, or personnel. It may also be airborne or internal (inside components or personnel) (FAO/IAEA 2009). Presence of an undesirable substance, the contaminant. For artificial diets, contaminants are often fungi or bacteria.
contingent valuation	Attempts to elicit consumer valuations of goods and services which are not usually traded in markets. Individuals are confronted with hypothetical choices and are asked either ‘willingness to pay’ or ‘willingness to accept compensation’ questions. This approach has been most widely used in the area of environmental economics (Pearce 1992). Survey-based economic method that is used to determine the monetary value of the benefits or costs of an environmental policy (Collin 2001). A method of estimating the value people put on, usually, non-market goods or costs by surveying their willingness to pay to receive or avoid them (NAL 2008). Refer to Enkerlin (this volume). See ‘willingness to pay (WTP)’.
continuous distribution	Individuals of a species are distributed continuously over their habitat, i.e. no large separations between individuals from one part of the habitat to another. Similar to a uniform distribution, and contrasts with a clumped distribution. Refer to Hendrichs et al. (this volume). See ‘distribution’, ‘clumped distribution’, ‘homogeneous distribution’, ‘fragmented distribution’, ‘island distribution’.
control chart	A graphical method for evaluating whether a process is or is not in a state of statistical control. The concept was developed by W.A. Shewhart. If a standard value is known for the parameter under consideration, the control limits on the chart are based on adopted standard values applicable to the statistical measures plotted on the chart. Limits on a control chart are used as criteria for signalling the need for action (ASQC 1996). A chronological graphical comparison of measured product characteristics with limits reflecting the ability to produce, derived from past experience (Chambers and Ashley 1984). Chronological graphical comparison of the specifications of all quality assessment and control parameters (Moore et al. 1985). To plot a parameter with predetermined limits on a time scale and to present this information in an easy to interpret graphical form such as on mean- or range-charts that have control limit lines (FAO/IAEA/USDA 2003). A chronological graphical comparison of actual product-quality characteristics with limits reflecting the ability to produce as shown by past experience on the product characteristics. Used to analyse data generated over a period of time. It fulfils three functions: 1) define a goal of an operation, 2) aid in attaining the goal, and 3) judge whether the goal has been reached (Feigenbaum 1961). A graphical chart with upper and lower control limits and plotted values of some statistical measure for a series of samples. Control limits are numerical calculations of the usual variation limits. Limits on a control chart are used as criteria for action (Charbonneau and Webster 1978). Refer to Calkins and Parker (section 8 and Box 2) (this volume) for a description and examples of control charts.
control strategy	Suppression, containment or eradication of a pest population (FAO 2006; IAEA 2003; FAO/IAEA/USDA 2003; Hendrichs et al., this volume). A strategy for controlling a pest population, e.g. suppression, eradication, containment, prevention (Hendrichs et al., this volume). A strategy for reducing or regulating a population in an area (Gordh and Headrick 2001). Refer to Hendrichs et al. (this volume). See ‘pest control’, integrated pest management (IPM)’, ‘suppression’, ‘eradication’, ‘containment’, ‘prevention’.
conventional pest management	Pest management according to conventional strategies and methods, usually implying that single control methods, especially chemical pesticides, are applied to reduce or suppress a pest population. See ‘integrated pest management (IPM)’.
copulation	The act of coupling or bonding during sexual intercourse; the state of being joined during sexual intercourse (Gordh and Headrick 2001, FAO/IAEA/USDA 2003). The period or process during which an intromittent organ (almost always of the male) introduces gametes into a reproductive tract of the opposite sex (Resh and Cardé 2003, Aluja and Norrbom 2001). The joining of male and female genital structures; mating (Pedigo 2002). See ‘insemination’, ‘fertilization’, ‘locking’, ‘mating duration’.
cordelitos	Baited (with a synthetic lure) and insecticide-treated wicks which attract and kill fruit flies; from Spanish. These may be released in large numbers from aircraft. Refer to Nagel and Peveling (this volume).
cost recovery	Obtaining back or recovering money spent directly or indirectly on something, a project or service. See ‘payback’.
cost-effective	An activity that generates sufficient value to offset it’s cost (Friedman 2007). To achieve a goal with the minimum of expenditure; to achieve a goal with an expenditure that makes the achievement viable in commercial terms (Oxford 1993). A measure of the extent to which money has been effectively spent on something. It is found by seeing whether the benefits that have resulted could have been obtained with a lower expenditure (Statt 1991). Achieving an objective in the least-cost way (Pearce 1992).
courtship	Traditionally viewed as communication between the sexes that brings about successful copulation. However, given that communication during copulation may influence fertilization success, courtship can in theory occur anytime during mating (Resh and Cardé 2003). An elaborate pattern of instinctive behaviour performed by some animals prior to mating (Leftwich 1973). A series of behavioural events between two conspecific individuals of opposite sex that may result in the mounting of the female by the male (Aluja and Norrbom 2001). The courting behaviour of male animals with the expectation of mating (FAO/IAEA/USDA 2003). See ‘lek’, ‘mating behaviour’, ‘mate-choice’.
critical ratio	The minimum overflooding ratio of sterile to wild males in the field needed for the SIT to reduce fertility in the wild population and suppress its density. Kean et al. (2007) provided a mathematical description of the critical overflooding ratio (Φc), the number of irradiated males that needs to be released per wild male to prevent the population from increasing. Refer to Hendrichs et al. (this volume) and Barclay (this volume).
critical release rate	The number of sterile males that must be released in a specified time period to achieve a critical ratio. (This rate is influenced by many biological variables, e.g. wild population density, survival and competitiveness of released males). Refer to Barclay (this volume). See ‘release’, ‘release rate’.
crop damage	A measurable loss of crop (plant) utility, most often including yield quantity, quality, or aesthetic appeal (Pedigo 2002). The adverse effect on plants or crops due to biotic or abiotic agents, resulting in economic loss (reduction of yield and/or quality) (Bijlmakers 2008). In agricultural entomology, damage to crop plants caused by the actions of insect pests, e.g. feeding damage to fruits, seeds, leaves.
crop residue	Any organic matter left in the field after the harvest of a crop plant, e.g. leaves, stalks, stubble, roots, hulls (NAL 2008). A crop is the plants grown by humans for particular purposes, usually edible plants grown for their fruits or foliage, etc. (Hill 1997). See ‘sanitation’, ‘cultural control’.
cross-bred	An animal resulting from crossbreeding (outbreeding) two distinctive varieties of a species (MH 1997), or from the fertilization of an organism from another organism with a different genetic constitution (Schlindwein 2006).
crossing-over	The reciprocal exchange of segments at corresponding positions along pairs of homologous chromosomes by symmetrical breakage and crosswise rejoining (NAL 2008). The reciprocal exchange of segments at corresponding positions along pairs of homologous chromosomes by symmetrical breakage and crosswise rejoining of the chromatids. It results in the recombination of alleles (Oxford 2006). The exchange of genetic material between paired homologous chromosomes during meiosis (MH 1997). The reciprocal exchange of polynucleotides between homologous chromosomes during meiosis (Hoy 2003). The exchange of genetic material between homologous chromosomes. Meiotic crossing over occurs during pachynema, and involves the non-sister strands in each meiotic tetrad. Each exchange results in a microscopically visible chiasma. Crossing over can also occur in somatic cells during mitosis. Exchange between sister chromatids can also occur, and is a sensitive indicator of DNA damage caused by ionizing radiations and chemical mutagens. Sister chromatid exchanges normally do not result in genetic recombination (King et al. 2006). The breaking during meiosis of one maternal and one paternal chromosome, the exchange of corresponding sections of DNA, and the rejoining of the chromosomes. This process can result in an exchange of alleles between chromosomes and gives rise to new character combinations (Schlindwein 2006, Burt and Trivers 2006). This is one of the essential biological mechanisms for creating genetic variation during sexual reproduction of eukaryotic organisms (Kahl 1995). See ‘chiasmata’, ‘pachytene’.
cryopreservation	The maintenance of cells under extremely cold conditions, such as liquid nitrogen (Gordh and Headrick 2001). Refer to Leopold (2007).
cryptic species	Reproductively distinct species that show little or no outward morphological differences, and thus are difficult to distinguish (Gordh and Headrick 2001). [Cryptic = hidden or concealed] See ‘sibling species’.
cucurbitacin	A chemical attractant for adult corn rootworms (Klassen, this volume).
cuelure	A synthetic lure (cuelure is a parapheromone) to attract fruit flies (IAEA 2003). A synthetic kairomone eliciting attraction of tephritid fruit flies (NAL 2008). See ‘parapheromone’, ‘ceralure’, ‘disparlure’, ‘gossyplure’, ‘hexalure’, ‘propylure’, ‘swormlure’, ‘trimedlure’.
cultural control	A pest management strategy that involves the use of production practices, such as crop spacing, crop rotation, planting and harvest dates, clean culture, irrigation, pruning and tillage operations, individually or in combination, to disrupt a pest’s life cycle (Gordh and Headrick 2001, USDA 1993). Purposeful manipulation of a cropping environment to reduce rates of pest increase and damage (Pedigo 2002). See ‘integrated pest management (IPM)’, ‘sanitation’, ‘crop residue’, ‘trap crop’.
cumulative recaptures	Accumulating or adding up the number of marked insects recaptured in a trap over time. Refer to Itô and Yamamura (this volume).
cuticular hydrocarbon	Chemicals (hydrocarbons) from the insect cuticle can serve as chemical messengers between insects (Howard and Blomquist 1982) and as identifiers of the geographical source of adults (Brown et al. 1998). See ‘contact pheromone’.
cytochrome oxidase	Terminal enzyme of the electron transport chain that accepts electrons from (i.e. oxidizes) cytochrome c and transfers electrons to molecular oxygen (Lackie and Dow 1995). Any of a family of respiratory pigments that react directly with oxygen in the reduced state. Also known as ‘cytochrome a3‘ (MH 1997). Cytochrome refers to the complex protein respiratory enzymes occurring within plant and animal cells in the mitochondria, where they function as electron carriers in biological oxidation (Hoy 2003).
cytology	Branch of biology dealing with the structure, behaviour, growth, and reproduction of cells, and the function and chemistry of cell components (MH 1997, King et al. 2006).
cytoplasm	The protoplasm of an animal or plant cell external to the nucleus (MH 1997, King et al. 2006). Substance contained within the plasma membrane excluding, in eukaryotes, the nucleus (Lackie and Dow 1995).
cytoplasmic incompatibility	Reproductive incompatibility between two populations caused by factors that are present in the cytoplasm. Often associated with micro-organisms (Hoy 2003). Occurs when factors in the egg cytoplasm prevent fusion of the sperm and egg nuclei (Pedigo 2002). Reproductive incompatibility between allopatric populations of the same species in which eggs fertilized by sperm from males infected with a rickettsial endosymbiont fail to hatch. This effect occurs chiefly in insects as well as some other arthropods, and the most studied and apparently most common of these reproductive parasites are Wolbachia spp. (NAL 2008).
data analysis	Data analysis is the process of looking at and summarizing data with the intent to extract useful information and develop conclusions (Wikipedia 2008). Organizational, mathematical or structural manipulation of data (database) to distil [extract the most important aspects of] higher levels of order or patterns (Gordh and Headrick 2001).
data layer	A data layer is a set of data on a particular subject, e.g. insect density in the field, insect population distribution, meteorological data, host animals, vegetation classification, crop, land use, soil type, geographical boundaries, satellite imagery, digitized topographical maps, demographic data. In using geographic information systems (GIS), many data layers may be used and are then related to each other. Refer to Cox and Vreysen (this volume) and Leak et al. (2008). See ‘geographic information systems (GIS)’.
data management	The systematic management of a large structured collection of information, that can be used for storage, modification and retrieval of data (Everitt 2006). Methodology of storing, manipulating, and retrieving data in a database. Aspects include entering, classifying, modifying and updating data and presenting output reports. Also, sorting, recording, and classifying data for making calculations or decisions (Friedman 2007). Raw information is collected, recorded, organized and analysed, and converted into a form where it may conveniently be used or stored (Statt 1991).
database	A structured collection of data that is organized in such a way that it may be accessed easily by a wide variety of application programmes (Everitt 2006). A collection of data stored on a computer storage medium in a common pool for access on an as-needed basis. The same pool of information can serve many applications, even those not anticipated at the time the database was created (Friedman 2007). A store of information, usually held in a computer, which is logically arranged for a certain use (Statt 1991). A large collection of data organized such that elements of information can be expanded, updated and retrieved rapidly for various tasks (Gordh and Headrick 2001). A large collection of information that has been coded and stored in a computer in such a way that it can be extracted under a number of different category headings (Isaacs 2000).
decision support	Use of various tools such as computer software to provide supporting information that enables an informed decision about an activity to be made. Refer to Cox and Vreysen (this volume).
declaration of eradication	A formal statement by an authority that a certain insect pest has been eradicated in a defined region. However, a particular procedure must be followed before a declaration can be made, i.e. two phases of monitoring must be conducted. The first phase involves the continual operation of traps to attempt to catch the insect while also continuing control actions. The second phase involves stopping control actions but continuing detection trapping and waiting for an appropriate period of time. Refer to Barclay et al. (this volume) for a detailed description of the required procedures to follow before eradication can be declared. Refer also to Barclay and Hargrove (2005).
defined diet	Diet in which all components are chemically pure and of known composition (Cohen 2004). Diet in which the constituents can be described (ideally consisting of only chemically pure constituents) (Vanderzant 1966). See ‘artificial diet’.
delayed sterility	Synonym for inherited sterility (IS) or F1 sterility (Carpenter et al., this volume). See ‘inherited sterility (IS)’, ‘partial sterility’, ‘full sterility’, ‘sterility’, ‘induced sterility’.
deleterious	Causing harm or damage (Oxford 2001). ‘Deleterious’ may be used in the context of harmful effects on chromosomes caused by radiation.
delta trap	Triangular insect trap [delta-shaped from the fourth letter of the Greek alphabet ‘Δ’] containing a lure, e.g. a sex pheromone, and coated with a sticky substance on the inside to hold the insect after it enters the trap (Cooper Mill 2008). See ‘attractive device’, ‘Jackson trap’, ‘pheromone trap’, ‘sticky trap’, ‘trap’, ‘wing trap’.
deme	A local population of a species consisting of potentially interbreeding individuals at a given locality (Gordh and Headrick 2001, Leak et al. 2008). A subpopulation of interbreeding individuals (Pedigo 2002, Schlindwein 2006). Assemblage of taxonomically closely related individuals (Hill 1997, Minks and Harrewijn 1987). A randomly mating population (Doncaster 2008). See ‘population’, ‘gene flow’, ‘area-wide’.
demographic	Pertaining to demography or parameters of populations. Demography is the statistical analysis of populations, including natality, mortality, migration, and sex; the rate of growth and age structure of populations, and the study of the factors which influence them (Gordh and Headrick 2001, MH 1997).
density	The number of individuals of a species per unit of habitat (Resh and Cardé 2003, Pedigo 2002).
density-dependence	The change of influence of environmental or physiological factors upon population size as population density increases (Gordh and Headrick 2001). A population-regulating factor changes proportionally in intensity with changes in population density (Pedigo 2002, MH 1997). Population of a species is regulated by its density (Collin 2001). The tendency for the birth rates or death rates to change as density of a population increases or decreases (Resh and Cardé 2003). Population growth can be density-dependent where either or both of birth rate and mortality depend on population size, usually in such a way as to eventually stabilize the population around some long-term mean value (Barclay, this volume). Contrast with density-independence. See ‘inversely density-dependent’, ‘density-independence’.
density-independence	The lack of change in population size as population density changes (Gordh and Headrick 2001). A population-regulating factor that causes mortality and is unrelated to a population’s density (Pedigo 2002, MH 1997). Factors operating in population regulation that are not related to population density, e.g. climate (Resh and Cardé 2003). Population growth can be density-independent where birth rate and mortality are independent of population size (Barclay, this volume). Contrast with density-dependence. See ‘density-dependence’.
derelict orchard	An orchard in very poor condition resulting from disuse and neglect (Oxford 2001).
deterministic model	A simulation model that offers an outcome with no allowance or consideration for variation. Deterministic models are well suited to predict results when the input is predictable (Friedman 2007). A model that contains no random or probabilistic elements (Everitt 2006). A model is a mathematical explanation applied to biological phenomena (Gordh and Headrick 2001). Each independent variable in the model may be assigned a predetermined value to observe its effect on other variables (FAO/IAEA 1973). See ‘stochastic model’, ‘model’, ‘modelling’.
developmental stage	A morphologically recognizable stage in the development of an insect during its life cycle, e.g. egg, larva or nymph, pupa, adult. Development is an orderly sequence of progressive changes resulting in an increased complexity of a biological system (King et al. 2006).
diapause	A dynamic state of low metabolic activity, with reduced morphogenesis, increased resistance to environmental extremes, and altered or reduced behavioural activity (Brown 1991). A syndrome of developmental, physiological, biochemical, and behavioural attributes that together serve to enhance survival during seasons of environmental adversity (Denlinger 2003). A programmed state of dormancy or arrest of development mediated by the neuroendocrine system, usually occurring in a species-specific stage of the life cycle. It may be induced obligatorily or facultatively in response to seasonal cues (daylength, temperature, food quality, etc.) (Resh and Cardé 2003, Pedigo 2002, Coombs and Hall 1998). A physiological condition or state of restrained development and reduced metabolic activity which cannot be directly attributed to unfavourable environmental conditions; an anticipated, typically long-term, cyclical interruption in growth or development of an organism due to one or more environmental factors that occur well before adverse environmental conditions are manifest (Gordh and Headrick 2001, Pedigo 2002, Coombs and Hall 1998). See ‘dormancy’.
dicentric	A chromosome or chromatid having two centromeres (King et al. 2006, Hoy 2003). Applied to a chromatid or chromosome with two centromeres, such as arises in an inversion heterozygote as a result of crossing-over between a normal and an inverted segment that does not include the centromere (Schlindwein 2006). See ‘centromere’, ‘acentric’, ‘monocentric’, ‘holokinetic’, ‘monokinetic’.
dichotomous spermiogenesis	Spermiogenesis is the series of morphological and chemical changes that transform the haploid spermatids resulting from the meiotic divisions of a spermatocyte into functional spermatozoa (King et al. 2006, Oxford 2006, MH 1997, Scott 1996). Dichotomous refers to the formation of two types of spermatozoa, i.e. apyrene and eupyrene, found in some insects, e.g. Lepidoptera. Refer to Carpenter et al. (this volume). See ‘apyrene’, ‘eupyrene’.
diet	The foods on which an animal feeds (Cohen 2004). If the diet is artificial, a synonym is ‘medium’, but usually ‘medium’ is used in the context of culturing micro-organisms (Singh 1977). See ‘artificial diet’, ‘defined diet’, ‘extruder’, ‘food processing’.
diet disposal	Disposing (getting rid of, throwing away) of insect diets after being used. Environmental concerns must be addressed when disposing of artificial diet (Parker, this volume; Dyck 2010). See ‘spent diet’, ‘artificial diet’.
dietary supplement	A product that is intended to supplement the diet. In insect rearing, supplements or additives may be included to improve competitive behaviour, e.g. sexual performance, dispersal. Some supplements are proteins, semiochemicals and micro-organisms. Refer to Parker (this volume), Robinson and Hendrichs (this volume), Niyazi et al. (2004). See ‘probiotic’.
diffusion	The process of movement or insect dispersal used in differential equations; it is measured by the coefficient, D, as used in diffusion equations. Refer to Itô and Yamamura (this volume) and Barclay (this volume). See ‘dispersal’.
dilution	Act of diluting (weakening or thinning) by modifying or adding other elements (Oxford 2001). In the context of insect dispersal, dilution refers to the recruitment of insects in a specified area from immigration or emergence, resulting in the dilution of a marked population in that area. Refer to Itô and Yamamura (this volume).
dimer	A dimer is a molecule or molecular complex consisting of two identical molecules linked together (Oxford 2008, 1990). A dimer is a chemical entity consisting of an association of two monomeric subunits (King et al. 2006). See ‘monomer’, ‘polymer’, ‘primer’.
dimeric locus	A locus that codes for an enzyme of two subunits. Heterozygotes for dimeric enzymes display three bands. Refer to Krafsur (this volume). See ‘dimer’, ‘locus’, ‘monomeric locus’.
dip	Special pool with water and insecticide through which cattle are forced to swim and thus become ‘dipped’ to control tsetse flies (Vale and Torr 2004). See ‘pour-on’, ‘chemical control’, ‘live-bait technology’.
diploid	Having two complete sets of chromosomes (Burt and Trivers 2006, Hoy 2003, Resh and Cardé 2003). Chromosomes are in homologous pairs, thus with two copies of each autosomal genetic locus (Lacker and Dow 1995). Possessing the full complement of maternal and paternal chromosomes (Pedigo 2002). A full set of genetic material, consisting of paired chromosomes, one chromosome from each parental set. Most animal cells except the gamete have a diploid set of chromosomes (Schlindwein 2006). Diploidy results from the fusion of the haploid egg nucleus and a haploid sperm nucleus (King et al. 2006, Oxford 2006). See ‘haploid’. ‘polyploid’.
direct benefits	Economic benefits from pest management activities received directly by agricultural producers, e.g. increased yield and quality of products, and reduced production costs (Enkerlin, this volume). See ‘benefit/cost analysis (BCA)’, ‘indirect benefits’.
direct sampling	Taking a direct sample of insects from the habitat, i.e. actual insects are collected, using traps or by dissecting host organisms (Vreysen, this volume). See ‘sampling’, ‘indirect sampling’.
disability-adjusted life year index (DALY)	An index that measures the burden of a disease — life years lost due to the disease (Murray 1994).
discount rate	A rate used in determining the present value of future cash flows (Friedman 2007). The rate at which future benefits and costs are discounted because of time preference or because of the existence of a positive interest rate (Pearce 1992). The discount rate is the real cost of deferring benefits, for example the interest rate minus the inflation rate would give a commercial discount rate. The actual discount rate applied may be more than this, if the opportunity costs for an investment were higher than the commercial interest rate. The discount rate could also be lower if a social rate of interest was applied, for example one could argue that a social discount rate of zero be applied if there was no difference between present and future values, for example for conservation or disease prevention. See ‘present value’, ‘net present value (NPV)’, ‘future value’, ‘economic return’, ‘rate of return’, ‘internal rate of return’.
discrete generations	Generations of an insect population where each generation is individually distinct, separate in time and clearly identifiable.
disease transmission	In medical and veterinary entomology, transmitting or passing on a disease, e.g. malaria, nagana, sleeping sickness. Transmission may be biological or mechanical. The passage of an infective parasite from an intermediate host (insect vector) to a definitive host (e.g. human), or vice versa (Gordh and Headrick 2001, Torre-Bueno 1978). See ‘vector’, ‘transmission’, ’parasitism’, ‘African animal trypanosomosis (AAT)’, ‘human African trypanosomosis (HAT)’.
disinfestation	A process or treatment which gets rid of an infestation of pests by destroying the pests infesting a commodity, e.g. fumigation or heat treatment of fruit destined for export. Refer to Bakri et al. (this volume).
disparlure	Synthetic sex pheromone of the gypsy moth Lymantria dispar (L.) (Gordh and Headrick 2001). A chemical substance that is a synthetic analogue of the sex pheromone produced by females, and it attracts male moths (Coombs and Hall 1998, NAL 2008). See ‘sex pheromone’, ‘ceralure’, ‘cuelure’, ‘gossyplure’, ‘hexalure’, ‘propylure’, ‘swormlure’, ‘trimedlure’.
dispersal	A non-directional movement of insects within or between habitats (Gordh and Headrick 2001). The process of scattering, spreading out, in various directions; an active or passive extension of territory (Pedigo 2002, Scott 1996). Movement of individuals out of a population (emigration) or into a population (immigration) (Hill 1997). See ‘migration’.
dispersion	The spatial arrangement of individuals in their habitat (Pedigo 2002). The distribution of the individuals of a species in space or on a surface (Scott 1996). See ‘distribution’.
distribution	The distribution of individuals (manner in which they are spread out over an area) may be described as uniform, random or clumped (Wikipedia 2008). Pattern in which a species is found in various areas, depending on climate, altitude, etc. (Collin 2001). Range of an organism or group in biogeographical divisions of the world; spatial arrangement or pattern of the members of a group (Hill 1997). The geographical area inhabited by a species (Bijlmakers 2008). The pattern of location of individuals in their habitat — how they are located in relation to one another. For examples of tsetse fly Glossina spp. distribution, refer to Rogers and Robinson (2004). See ‘clumped distribution’, ‘homogeneous distribution’, ‘continuous distribution’, ‘fragmented distribution’, ‘island distribution’, ‘dispersion’.
diurnal rhythm	Regular periodicity in the pattern of biological activity or behaviour of animals in which the pattern recurs daily during daylight (Scott 1996). Contrast with nocturnal.
diversity	Differences in appearance, habits, etc. in a group of animals or plants; also species variety and richness (Hill 1997, Collin 2001). The distribution and abundance of different plant and animal communities and species within an area; the number of species in a community or region (USDA 1993). See ‘biodiversity’.
DNA	Deoxyribonucleic acid — a compound of deoxyribose, phosphoric acid, and nitrogen bases. A DNA molecule consists of two strands in the shape of a double helix (Pedigo 2002). The molecule that encodes genetic information. DNA is a double-stranded molecule held together by weak bonds between base pairs of nucleotides. The four nucleotides in DNA contain the bases adenine, guanine, cytosine and thymine (Schlindwein 2006). See ‘RNA’.
DNA repair	The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions (NAL 2008). Following DNA damage from ionizing radiation, a molecular process in which the DNA is repaired. This is mentioned in the context of the high radioresistance in Lepidoptera. Refer to Carpenter et al. (this volume).
domestication	The process of breeding for one or more desirable characteristics in plants and animals (NAL 2008). The adaptation of an animal or plant through breeding in captivity to a life intimately associated with, and advantageous to, humans (MH 1997). The conversion of wild animals into domestic animals. Domesticated species show a much wider variation of form than the corresponding wild species (Scott 1996). See ‘strain domestication’, ‘selection’, ‘colonization’.
dominant conditional lethal (DCL)	Dominant lethal mutation which is expressed only under a certain set of permissive conditions, e.g. temperature, or only in females as described for Lepidoptera in Marec et al. (2005). See ‘dominant gene’, ‘lethal gene’.
dominant gene	An allele of a character which is fully expressed in a heterozygote. A dominant gene is the stronger gene of a pair of alleles, expressed as fully when in single dose (i.e. heterozygous) as it is when present in double dose (i.e. homozygous). The opposite is recessive (Resh and Cardé 2003, NAL 2008). See ‘gene’.
dominant lethal induction	Use of any mechanism to induce a dominant lethal mutation in germ cells. See ‘dominant gene’, ‘lethal gene’, ‘dominant lethal mutation (DLM).
dominant lethal mutation (DLM)	Any mutation which kills an individual which is heterozygous for it. See ‘dominant gene’, ‘lethal gene’.
dormancy	A seasonally recurring period in the life cycle when growth, development, and reproduction are suppressed (Pedigo 2002, Weeden et al. 2000). A condition of resting or quiescence, hibernation or aestivation, alive but not growing (Hill 1997, MH 1997). State of an animal or plant, where metabolism is slowed during a certain period of the year (Collin 2001, Scott 1996). An imperfectly understood physiological phenomenon that is generally regarded as a state of suspended development or reduced metabolic activity (Gordh and Headrick 2001). See ‘diapause’.
dose	A general term denoting the quantity of radiation or energy absorbed in a specific mass (FAO/IAEA 2009). See ‘absorbed dose’.
dose distribution	See ‘absorbed-dose distribution’.
dose fractionation	Process where the required dose is delivered over time in a series of smaller irradiations (K. Mehta, personal communication). A method of administering radiation in which relatively small doses are given daily or at longer intervals (Borders 1991).
dose mapping	Measurement of the absorbed dose distribution within a process load through the use of dosimeters placed at specific locations within the process load (FAO 2006). See ‘absorbed-dose mapping’.
dose rate	See ‘absorbed-dose rate’.
dose-response curve	The functional relationship between dose and effect (Borders 1991).
dosimeter	A device that, when irradiated, exhibits a quantifiable change in some property of the device which can be related to absorbed dose in a given material using appropriate analytical instrumentation and techniques (FAO 2006, ISO/ASTM 2004a).
dosimetry	A system used for determining absorbed dose, consisting of dosimeters, measurement instruments and their associated reference standards, and procedures for the system’s use (FAO 2006, ISO/ASTM 2004a).
double-stranded RNA (dsRNA)	A structure that occurs when complementary base sequences in single-stranded RNA form a duplex (Oxford 2006). An RNA duplex in which a messenger RNA is bound to an antisense RNA containing a complementary sequence of bases. Endogenous or exogenous dsRNAs provide a powerful means of silencing gene expression (King et al. 2006).
droopy wing syndrome	Wings of reared fruit flies drooped due to mechanical damage from sifting pupae while they were developing. Evidently indirect flight muscles did not insert properly into the cuticle of the exoskeleton, resulting in non-flying flies (Little and Cunningham 1978). Refer to Calkins and Parker (this volume).
drug resistance	A decreased reactivity of living organisms to the injurious actions of certain drugs and chemicals (MH 1997). The relatively enhanced resistance of an organism to the action of a drug. It may be caused by induction of an enzyme acting on the drug, by mutation, or by the acquisition of a plasmid coding for drug resistance (Oxford 2006). Resistance in an organism to a drug administered for the control of a disease, e.g. trypanosome parasites are becoming resistant to drugs administered to control trypanosomosis. Refer to Feldmann et al. (this volume). See ‘African animal trypanosomosis (AAT)’.
dry storage of radiation source	When a radiation source is not in use, dry storage involves shielding the source by lead or other appropriate high-atomic-number material (Bakri et al., this volume). See ‘wet storage of radiation source’, ‘panoramic irradiator’, ‘gamma irradiator’.
Dyar’s Rule	Insects double their weight at each moult, and thus their cells need to divide only once per moulting cycle (Hutchinson et al. 1997, Behera et al. 1999). Refer to Bakri et al. (this volume). Dyar’s Law -- An empirical observation that indicates a geometric progression in head width in successive instars of most holometabolous larvae, as proposed by H. G. Dyar in 1890 (Resh and Cardé 2003, Gordh and Headrick 2001, Torre-Bueno 1978).
dye	A chemical used to colour insects internally or externally, and thereby mark them for future identification purposes. Internal dyes are usually added to an artificial diet, and may be fat-soluble, while external dyes are usually fluorescent powders to permit later identification under ultraviolet light. Refer to Parker (this volume), and Dyck (2010). See ‘fluorescent dye’, ‘marking’, ‘mark-release-recapture’.
dynamics	The forces which stimulate development or change within a system or process (Oxford 2008). Active, as opposed to static (Gordh and Headrick 2001). See ‘population dynamics’.
economic damage	The amount of pest-induced injury that justifies the cost of applying pest control measures (Gordh and Headrick 2001, Hill 1997).
economic injury level	The level of injury to a crop by a pest at which the implementation of control measures becomes cost effective (Gordh and Headrick 2001). The lowest pest population density that will cause economic damage (Hill 1997). The degree of crop damage at which economic losses become significant (Maxwell and Jennings 1980). The amount of pest damage equal to the cost of preventing damage (Daly et al. 1998). See ‘economic threshold’, ‘cost-effective’, ‘economic damage’, ‘economic loss’.
economic loss	For an agricultural crop, the fraction of the realizable yield that is lost to the combined effect of all pests and the physical forces of the environment (Resh and Cardé 2003). Situation in which a producer does not earn the level of profit that would justify remaining in business in the long run (Friedman 2007).
economic return	Financial profit or economic benefit obtained from an investment. See ‘rate of return’, ‘internal rate of return’, ‘discount rate’, ‘net present value’, ‘present value’.
economic threshold	The pest density at which management action should be taken to prevent an increasing pest population from reaching the economic injury level (Gordh and Headrick 2001, Daly et al. 1998, Hill 1997). A pest population level at which economic damage begins to occur; this level may vary depending upon crop and locality (USDA 1993). See ‘economic injury level’, ‘economic damage’.
economies of scale	Reductions in the average cost of a product in the long run, resulting from an expanded level of output (Pearce 1992). Reduction of the costs of production of goods due to increasing the size of the producing entity and the share of the total market for the good (Friedman 2007). The advantages resulting from a large, as opposed to a small, scale of operation in an organization. They include lower unit costs, greater purchasing power by buying in bulk, opportunities for training, etc. (Statt 1991).
ecosystem	A dynamic complex of plant, animal and micro-organism communities and their abiotic environment interacting as a functional unit (FAO 2006). A community of organisms and their interaction with the physical environment (Resh and Cardé 2003). An ecological system formed of component members (a community) and the abiotic environment surrounding the system (Gordh and Headrick 2001, Hill 1997, Walker and Cox 1995).
ectoparasitic	An ectoparasite is a parasite that lives on the surface or within the skin of its host (Resh and Cardé 2003). Ectoparasites include fleas and lice (Gordh and Headrick 2001). See ‘parasitism’, ‘endoparasitic’.
ectopic	Meaning ‘out of place’, occurring in an unusual place or an unusual form or manner. In developmental genetics, the word ‘ectopic’ is sometimes used to describe the expression of a regulatory gene in the wrong place (King et al. 2006, Oxford 2006). Ectopic expression is the expression of a gene in all tissues (Robinson, this volume).
effective population size	Approximately the number of successfully reproducing individuals in a population (Krafsur, this volume; Ayala and Kiger 1984). The average number of individuals in a population that contributes genes to succeeding generations. If the population size shows a cyclical variation as a function of season of the year, predation, parasitism, and other factors, the effective population size is closer to the number of individuals observed during the period of maximal contraction (King et al. 2006). The size of a real population, adjusted mathematically to account for varying sex ratios, degrees of inbreeding, etc., so that different populations may be compared (Scott 1996).
egg mass	The group of eggs laid by a female in a single egg-laying event (NAL 2008).
egg raft	A mass of eggs that floats on water, produced for example by Culex fatigans mosquitoes (MH 1997). Refer to Robinson (this volume).
eggshell	The typically hard, external covering of an egg; collectively, the chorion and vitelline membrane of an insect egg (Gordh and Headrick 2001).
ejaculate	Seminal fluid emitted from the body of the male (Gordh and Headrick 2001). The semen released in a given copulatory interaction (King et al. 2006).
electromagnetic radiation	Kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously (Oxford 2008). Radiation consisting of associated and interacting electric and magnetic waves that travel at the speed of light (Borders 1991). Radiation from synchro systems and magnetic waves travelling at the speed of light. (Koelzer 2008).
electron accelerator	Device the accelerates a beam of electrons to high energy, and emits it towards some material (with the intention of modifying its properties) (K. Mehta, personal communication). Device to accelerate electrically charged particles to high energies (Koelzer 2008).
electron beam	A stream of electrons, generally emitted from an electron accelerator (K. Mehta, personal communication). See ‘electron accelerator’.
electroretinogram	Device to measure the quality of vision (Agee and Park 1975). Refer to Calkins and Parker (this volume) and Scott (1996).
elemental marker	Using chemical elements, e.g. stable isotopes, instead of dyes to mark insects (Hood-Nowotny and Knols 2007, FAO/IAEA 2009). Refer to Parker (this volume). See ‘isotope’, ‘dye’.
embryogenesis	The formation of an embryo from an egg and the processes of its development (Oxford 2006, MH 1997). The development of the embryo within an egg (Gillett 1971).
embryonic arrest	Cessation of embryonic development, and death of the embryo (Vreysen, this volume).
emergence	The escape of the adult insect from the cuticle of the pupa (FAO/IAEA/USDA 2003). The escape of an adult winged insect from its cocoon, pupal case or nymphal integument (Gordh and Headrick 2001, Bijlmakers 2008, Torre-Bueno 1978). See ‘Tanaka box’, ‘plastic adult rearing container (PARC)’, ‘tower system’.
emigration	Movement of organisms out of a particular area (Hill 1997, Pedigo 2002). The movement of individuals out of a population (Bijlmakers 2008). The movement of individuals, groups or populations from one place to another place (Gordh and Headrick 2001). See ‘migration’, ‘immigration’.
endoparasitic	An endoparasite lives within the body of its host (Resh and Cardé 2003); any organism that develops as a parasite within the body of another organism at the expense and to the detriment of the ‘host’ (Gordh and Headrick 2001, Coombs and Hall 1998). See ‘parasitism’, ‘ectoparasitic’.
endosymbiont	An organism that lives within another organism in a symbiotic relationship, e.g. ants, termites and other wood-feeding insects contain endosymbiotic bacteria that digest cellulose and make it available as food (Resh and Cardé 2003, Burt and Trivers 2006). Internal symbionts are generally on the gut wall or inside the Malpighian tubules of an insect (Jolivet 1998). Symbiotic organisms (bacteroids/rickettsia-like organisms) living in the digestive tract (Leak 1999). Symbionts that live intracellularly or within hemocoel (Daly et al. 1998). An example of an endosymbiont is the genus Wolbachia (Robinson and Hendrichs, this volume). See ‘symbiont’.
enforcement	The cooperation of whole communities is required for area-wide integrated pest management programmes to succeed, and if cooperation is not voluntary then sometimes it has to be enforced by appropriate authorities. Quarantine practices, bylaws, agreements and pest control actions may require enforcement (Dyck, Regidor Fernández et al., this volume).
entomopathogen	An organism that causes an insect disease (Coombs and Hall 1998, Resh and Cardé 2003, Coppel and Mertins 1977).
entry	Movement of a pest into an area where it is not yet present, or present but not widely distributed and being officially controlled (FAO 2006, FAO/IAEA/USDA 2003). See ‘established pest’, ‘exotic species’, ‘native species’, ‘invasive species’.
environment	The complex of physical and biotic factors within which an organism exists (King et al. 2006, Collin 2001, Allaby 1994 ). The total of the natural conditions under which animals live, including climatic, geographic, physiographic and faunal conditions (Gordh and Headrick 2001, Porteous 1996). The sum total of external influences acting upon an organism including physical, chemical and biotic factors (Hill 1997).
environmental compatibility	The extent to which a technology, e.g. the SIT, is compatible with the environment. See ‘environment-friendly’.
environmental control	Control of the environment, e.g. temperature, relative humidity, in an insect mass-rearing facility, using engineered systems and appropriate equipment to achieve the level of control required. Often referred to as ‘controlled environment’. Refer to Parker (this volume).
environmental impact assessment	Environmental analysis that evaluates the positive and negative changes to the environment conditions at and around a particular site of a proposed project. Evaluation of the effect upon the environment of, for example, a large construction programme (Collin 2001). The identification and evaluation of the environmental consequences of a proposed development, and of measures intended to minimize adverse effects (Allaby 1994). The assessment is embodied in an environmental impact statement. This statement is a tool for decision making; it describes the positive and negative effects of the undertaking and cites alternative actions (NAL 2008, USDA 1993).
environmental impact quotient (EIQ)	A relative value that estimates the environmental impact of a pesticide, by taking into account toxicity to natural enemies, wildlife, and humans, degree of exposure, aquatic and terrestrial effects, soil chemistry, etc. (Weeden et al. 2000). An economic value for the environmental damage of pesticides (Kovach et al. 1992; Mumford, this volume).
environmental risk	The risk that methods of pest management (e.g. insecticides, the SIT, operating an insect mass-rearing facility), or even increasing agricultural production, might harm the environment must be assessed and prevented or at least managed. Risk mitigation is important for protecting the environment. Refer to Nagel and Peveling (this volume). The Precautionary Principle is the belief that even if there is scientific uncertainty regarding a risk and its consequences, preventive measures may be justified (Webster 2008).
environment-friendly	Not harmful to the environment (Collin 2001). See ‘environmental compatibility’.
epidemiology	The study of development and spread of a disease throughout a host population (Hill 1997). Science of the study of disease in populations (Fenner et al. 1987).
equilibrium	State of balance. Fluctuation around an apparent average state, where the average state is also changing through time. A stable population stays at the same level (same number of individuals in an area) since numbers entering and leaving the population are approximately in balance (Collin 2001, Allaby 1994, Pedigo 2002, Gordh and Headrick 2001). In a population, the condition in which the frequencies of allelic genes are maintained at the same values from generation to generation (MH 1997). Equilibrium in the number of individuals in a population, in the genotypes present in a population, and among groups within the population. Refer to Barclay (this volume), Klassen and Curtis (this volume), Krafsur (this volume), Franz (this volume).
eradication	Application of phytosanitary measures to eliminate a pest from an area (FAO 2006; IAEA 2003; FAO/IAEA/USDA 2003; Resh and Cardé 2003; Hendrichs et al., this volume). A type of regulatory-control programme in which a target pest is eliminated from a geographical region (Gordh and Headrick 2001). Complete and total elimination of a group of organisms from an area (Pedigo 2002). The elimination of a (tsetse) species from a given area ‒ it does not mean global elimination (extinction) (Leak et al. 2008). The complete elimination of a pest species; for some agricultural pests, this may mean the reduction of the pest populations to non-detectable levels (USDA 1993). Refer to Hendrichs et al. (section 2.2.) (this volume). Pest free area = An area in which a specific pest does not occur as demonstrated by scientific evidence and in which, where appropriate, this condition is being officially maintained (FAO 2006, IAEA 2003). See ‘extinction’, ‘freedom from pests’, ‘insect-free’, ‘fly-free’, ‘pest free area’, ‘pest free field’, ‘pest free status’, ‘pest free zone’, ‘tsetse-free zone’, ‘strategic option’.
established pest	A pest species that is expected, for the foreseeable future, to be present in an area. This species may have been in the area for a very long time, e.g. native pest, invaded or ‘entered’ the area long ago, or become established recently. It is expected that the pest is, or has become, a part of the local community of organisms and the ecosystem, fits into a suitable habitat, and its population dynamics is adjusted to local natural enemies. See ‘establishment’, ‘entry’, ‘exotic species’, ‘native species’, ‘invasive species’, pest establishment’.
establishment	See ‘pest establishment’, ‘established pest’.
eupyrene	A type of spermatozoa produced by Lepidoptera during spermatogenesis, having correctly formed chromatin, that fertilizes eggs (Gordh and Headrick 2001, King et al. 2006). Contrasts with apyrene spermatozoa. See ‘apyrene’, ‘dichotomous spermiogenesis’.
evolutionary genetics	Evolution from a genetic and molecular perspective; the genetic mechanisms of evolution. The study of evolution at the molecular level to understand the mechanisms of evolution and to clarify the evolutionary history of genes or species at the molecular level. For a population to evolve, the gene frequencies of that population must undergo change. The major tenets of the evolutionary synthesis, then, is that populations contain genetic variation that arises by random mutation and recombination; that populations evolve by changes in gene frequency brought about by random genetic drift, gene flow, and especially natural selection. This field of study attempts to account for evolution in terms of changes in gene and genotype frequencies within populations, and the processes that convert the variation with populations into more or less permanent variation between species. The central challenge of evolutionary genetics is to describe how the evolutionary forces shape the patterns of biodiversity observed in nature (SEP 2008, Wikipedia 2008). Refer to Krafsur (this volume), Avise (2004), Li (1997), Smith (1998), Doncaster (2008), UG (2006), McClean (1997), Fitch (1997). See ‘biodiversity’, ‘Hardy-Weinberg theorem’.
exclusion	Synonym for ‘prevention’. Prevention is defined as the application of phytosanitary measures in and/or around a pest free area to avoid the introduction of a pest (Hendrichs et al., this volume). The application of regulatory and phytosanitary measures to prevent the introduction or re-introduction of a pest into a pest free area (IAEA 2003). Control of a pest organism by excluding it from an area or country, often by use of phytosanitary legislation (Hill 1997). See ‘prevention’, ‘containment’, ‘pest free area’, ‘invasive species’.
exotic species	Organisms that are not native to a particular country, ecosystem or ecoarea (applied to organisms intentionally or accidentally introduced as a result of human activities) (FAO 2006, FAO/IAEA/USDA 2003). Not native, introduced from abroad (Coppel and Mertins 1977). Species that is introduced, foreign, non-endemic; a foreign animal or plant species that is not acclimatized (Hill 1997). An organism that evolved in one part of the world and that now occurs either accidentally or intentionally in a new region (Bijlmakers 2008). See ‘entry’, ‘established pest’, ‘native species’, ‘invasive species’.
externalities	External costs (externalities) are the harmful effects arising from pest control operations, which affect parties other than the pest control decision-maker, but for which no compensation is paid to the persons harmed (Reichelderfer et al. 1984). Externalities are the environmental and social impacts on society from actions such as pest management operations. Refer to Klassen, Mumford, Whitten and Mahon, and Enkerlin (this volume). In economics, a cost or benefit attributable to an economic activity which is not reflected in the price of the goods or services being produced. Thus damage to the environment may not be counted as a cost (or environmental protection as a benefit) in production (Allaby 1994).
extinction	The eradication of a species from an area, or possibly even from the earth in a range-wide species extinction. The act or process of destroying life or eliminating it (Gordh and Headrick 2001). Annihilation; the death or extinguishing of a species or a population (Hill 1997). Dying out of a species (Collin 2001). The worldwide death and disappearance of a specific organism or group of organisms (MH 1997). In evolutionary history, many species have become extinct, but this has not occurred as a consequence of human efforts directed specifically at that result. See ‘eradication’, ‘freedom from pests’, ‘insect-free’, ‘fly-free’, ‘pest free area’, ‘pest free field’, ‘pest free status’, ‘pest free zone’, ‘tsetse-free zone’.
extruder	Machine that, after processing and sterilizing insect artificial diet, forces out (extrudes) the diet on to trays or into containers. Extruders are extensively used in the food processing industry, providing versatility and high output (Cohen 2004). Refer to Parker (this volume). See ‘diet’, ‘food processing’.
F1 generation	The first filial generation; the first generation following the parental (P) generation (King et al. 2006). The first generation formed by crossing two parental lines (Burt and Trivers 2006).
F2 generation	The second filial generation; the progeny produced by intercrossing or self-fertilization of F1 individuals (King et al. 2006).
facility design	The engineering design, layout and plans for an insect rearing facility (Dowell et al., this volume; Dyck 2010; IAEA 2008a; Fisher 2002; Phillimore 2002; Wyss 2002; Leppla and Eden 1999; Nordlund 1999; Wood and Wendel 1999; Oborny 1998; Fisher 1984; Fisher and Leppla 1985; Griffin 1984a, b; Harrell and Gantt 1984; Kakinohana 1982; Marroquin 1985; Owens 1984; Schwarz et al. 1985).
fauna	The collective animal life of any region, place or area (Gordh and Headrick 2001, Torre-Bueno 1978). The animal life characteristic of a particular region or environment (MH 1997). See ‘flora’.
feasibility assessment	An assessment of the feasibility of conducting a programme, e.g. an AW-IPM programme. It involves many aspects, e.g. financial budgets and a benefit/cost analysis, economic development, organization and administrative/political matters, work plan, pest impact, biological procedures, and environmental issues. Refer to Dyck, Reyes Flores et al. (this volume), Mumford (this volume), and Cox and Vreysen (this volume). See ‘decision support’.
fecundity	The number of eggs produced by a female during her lifetime (Gordh and Headrick 2001). The rate at which females produce eggs (Pedigo 2002). The innate potential reproductive capacity of the individual organism (MH 1997). See ‘infecundity’.
feedback loop	Feedback refers to the influence of the result of a process upon the functioning of the process (King et al. 2006); information about the output of a system is used to influence the input to that system, and such feedback may increase the input to the system. A cyclic system of components participating in feedback forms a feedback loop (Oxford 2006). Returning output information to the beginning of a process for correcting discrepancies between intended and actual performance or for the maintenance of current process standards and procedures (Chambers and Ashley 1984, Moore et al. 1985). In the context of insect mass-rearing and quality control, quality assessments provide an ongoing check on the quality of insects being produced, providing an opportunity to correct any quality problems; this acts as a feedback loop to the production process. Refer to Calkins and Parker (this volume), Dowell et al. (this volume), and Dyck (2010). See ‘quality control (QC)’.
feeding stimulant	Substance that increases the appetite of an organism, usually an insect pest. Feeding stimulants are often used in combination with biopesticides to ensure that insects ingest lethal doses of toxin (Coombs and Hall 1998). Chemical compounds can be added to attract insects to, and stimulate feeding on, baits. Refer to Nagel and Peveling (this volume), Mangan (this volume), Nigg et al. (2004). Also feeding stimulants may be added to artificial diets to encourage neonate insects to feed on the diet. Refer to Dyck (2010). See ‘bait’, ‘bait spray’. Also see ‘artificial diet’, ‘diet’.
female relative performance index (FRPI)	Relative measure of the mating propensity of females, and indicates the degree of sexual compatibility (or isolation) between two strains/populations of insects. The mathematical formula for this quality control test is given in Calkins and Parker (Box 1) (this volume) and FAO/IAEA/USDA (2003). See ‘isolation index (ISI)’, ‘relative isolation index (RII)’, ‘male relative performance index (MRPI)’, ‘assortative mating’.
female-specific trap	A trap designed to attract and catch only female insects. Refer to Franz (this volume), Vreysen (this volume), IAEA (2003). See ‘trap’.
fertility	Ability to reproduce (Torre-Bueno 1978). The ability to reproduce or produce viable offspring (Gordh and Headrick 2001, King et al. 2006). The rate at which fertilized eggs (zygotes) are produced (Pedigo 2002). See ‘zygote’.
fertilization	Union or fusion of male and female gametes to form a diploid zygote. In insects, fertilization is characterized by mature sperm moving through the micropyle of an egg to unite with the female pronucleus (Gordh and Headrick 2001, King et al. 2006, Leftwich 1973, Torre-Bueno 1978, Watson 1976). See ‘gamete’, ‘diploid’, ‘zygote’, ‘fusion’.
filariasis	A disease transmitted by mosquitoes or other nematocerous Diptera, caused by the presence of microscopic nematodes (filaria) (Gordh and Headrick 2001). See ‘vector’, ‘transmission’, ‘parasitism’, ‘pathogen’.
filter rearing system (FRS)	This system for insect rearing is described by Parker (this volume). The concept involves maintaining a small colony at a low density, or even under semi-natural conditions, and therefore assumedly a low-selection pressure. Surplus insects from this low-density mother stock or clean stream are fed into a high-density amplification chain, leading up to the final insects to be released. The important feature is that no individuals are ever fed from the amplification stages back to the mother stock. The low-density rearing conditions of the filter can be supplemented with any further conditions deemed desirable, e.g. host plant, mating competition or pheromone response, and each generation the non-performing individuals are eliminated. A filter rearing system can provide a means to control the selection pressure on the mother stock used for the colony while avoiding many of the worst traits from the pressure of mass-rearing. Any undesirable traits selected for in the high-density amplification stages have only three or four generations to accumulate before release, and do not affect the mother stock. A further advantage is that, if it is desired to replace the strain with a new one, a new mother stock can be set up in parallel with the old one, and amplification easily switched from one to the other. Refer to Calkins and Parker (this volume), Franz (this volume), Robinson and Hendrichs (this volume). See ‘colony’.
fitness	The survival value and the reproductive capability of a given genotype as compared with the average of the population or of other genotypes in the population (Oxford 2006, King et al. 2006). The environment, and competition for survival within it, determine which individuals are fittest to survive and propagate their genes in the next generation (Doncaster 2008). Genetic fitness. See ‘survival’, ‘fertility’.
fixed cost	Cost that remains constant regardless of output. Fixed costs of a business include salaries of executives, interest expense, rent, depreciation, and insurance expenses. They contrast with variable costs (direct labour, materials costs) and semivariable costs, which vary, but not necessarily in direct relation to sales (Friedman 2007). See ‘variable cost’.
fixed-wing aircraft	Conventional aircraft with wings fixed or permanently attached to the fuselage or body of the aircraft. Contrast with helicopter. See ‘helicopter’.
flight ability	Flight is the movement and active locomotion in the air of adult insects with the aid of wings that are powered by muscles (Gordh and Headrick 2001; Scott 1996; Leftwich 1973, 1976). Adult capability to achieve a defined flight performance; a routine quality control test (FAO/IAEA/USDA 2003). Refer to Calkins and Parker (this volume), Dyck (2010). See ‘quality control’, ‘product control’.
flight tube	A plastic tube used in a flight ability test (FAO/IAEA/USDA 2003; Calkins and Parker, this volume; Dyck 2010). Observations are made on the ability of adults to fly out of the tube. See ‘flight ability’.
flora	The plant life characterizing a specific geographic region or environment (MH 1997, Allaby 1994). Wild plants which grow naturally in a certain area (Collin 2001). See ‘fauna’.
fluorescent dye	A dye which fluoresces under ultraviolet light. A powdered dye (various colour are available) is dusted onto adult insects to mark them. Refer to Parker (this volume), Dowell et al. (this volume), Dyck (2010). See ‘dye’, ‘marking’, ‘mark-release-recapture’.
fly-free	The FAO defines ‘free from’ as follows: Without pests (or a specific pest) in numbers or quantities that can be detected by the application of phytosanitary procedures (FAO 2006). An area where flies of a particular pest species are not present, i.e. free of flies, either due to natural causes, e.g. unsuitable habitat or climate, or to eradication resulting from an area-wide integrated pest management programme. Refer to Barclay et al. (this volume), Enkerlin (this volume), Feldmann et al. (this volume), Hendrichs et al. (this volume). See ‘eradication’, ‘extinction’, ‘freedom from pests’, ‘insect-free’, ‘pest free area’, ‘pest free field’, ‘pest free status’, ‘pest free zone’, ‘tsetse-free zone’.
follicle	The ovarian follicle is a sac or tube of cells in the ovary enclosing a developing ovum (Leftwich 1973, Torre-Bueno 1978). Follicle cells, not derived from germ cells, cover oocytes and contribute to their development (Resh and Cardé 2003, Gordh and Headrick 2001). Refer to Vreysen (this volume). See ‘ovary’, ‘ovariole’.
food chain	A trophic path or succession of populations through which energy flows as a result of feeding; each provides food for the next (Gordh and Headrick 2001, Collin 2001, Allaby 1994, Porteous 1996). The scheme of feeding relationships by trophic levels which unites the member species of a biological community (MH 1997). See ‘food web’, ‘ecosystem’.
food irradiation	Processing of food products by ionizing radiation [specifically gamma rays, X-rays or accelerated electrons as specified in the Codex General Standard for Irradiated Foods] to, among other things, control foodborne pathogens, reduce microbial load and insect infestation, inhibit the germination of root crops, and extend the durable life of perishable produce (ISO/ASTM 2003). See ‘irradiation’, ‘ionizing radiation’, ‘gamma radiation’, ‘X-ray’, ‘electron accelerator’.
food processing	Manufacturing foods, usually on a large scale, using any of a wide variety of processing techniques, most often with the goal of preserving food for the market (NAL 2008). Food processing is the set of methods and techniques used to transform raw ingredients into food for consumption by humans and animals. Food processing often takes clean, harvested or slaughtered and butchered components, and uses these to produce attractive and marketable food products (Wikipedia 2008). See ‘diet’, ‘extruder’.
food residue	Regarding insect diets, food remaining after insects have completed their development. See ‘diet disposal’.
food safety	The fitness of a food for human consumption (NAL 2008). Food safety is a scientific discipline describing the handling, preparation, and storage of food in ways that prevent foodborne illness (Wikipedia 2008). See ‘biosafety’, ‘genetically modified organism (GMO)’.
food security	Food security exists when all people, at all times, have access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life (FAO). Access by all people, at all times to sufficient food for an active and healthy life. Food security includes at a minimum: the ready availability of nutritionally adequate and safe foods, and an assured ability to acquire acceptable foods in socially acceptable ways (NAL 2008). See ‘biosecurity’.
food web	A complex of food chains that connect populations in an ecosystem (Gordh and Headrick 2001, Collin 2001, Allaby 1994, Porteous 1996). A modified food chain that expresses feeding relationships at various, changing trophic levels (MH 1997). See ‘food chain’, ‘ecosystem’.
founder effect	When a new population is derived from a few immigrants, these founders represent a very small sample of the genetic pool to which they formally belonged; natural selection operating on this restricted variety soon yields gene combinations quite different from those found in the ancestral population, or those of a second small sample of founders (Doncaster 2008, Gordh and Headrick 2001). The principle that when a small sample of a larger population establishes itself as a newly isolated entity, its gene pool carries only a fraction of the genetic diversity represented in the parental population. The evolutionary fates of the parental and derived populations are thus likely to be set along different pathways because the different evolutionary pressures in the different areas occupied by the two populations will operate on different gene pools (NAL 2008, King et al. 2006). A high frequency of a particular allele in a population resulting from the presence of the allele in one or more of a small number of individuals from whom the population is descended (Oxford 2006). Refer to Parker (this volume) and Dyck (2010). Genetic drift observed in a population founded by a small non-representative sample of a larger population (Schlindwein 2006, Ayala and Kiger 1984). Speciation resulting from the establishment of a small population in an entirely new area and the subsequent divergence of the resulting population from the parent stock (Auburn 2008). See ‘colony’, ‘bottleneck’, ‘genetic drift’, ‘founding population’.
founding population	The insects that are collected from a wild population and used to initiate and found (lay the base for) an insect colony in a laboratory (Dyck 2010). Refer to Parker (this volume). See ‘founder effect’, ‘colony’.
fractionated dose	See ‘dose fractionation’.
fragmented distribution	Distribution of a species in a fragmented pattern, i.e. occupied habitats are not contiguous due to, for example, patches of unsuitable habitat in between the occupied habitats. Some tsetse fly species have a fragmented distribution (Feldmann et al., this volume). Refer to Hendrichs et al. (this volume). See ‘distribution’, ‘clumped distribution’, ‘homogeneous distribution’, ‘continuous distribution’, ‘island distribution’.
free radical	A molecular fragment or an ion that has one or more unpaired electrons, rending it highly reactive (Porteous 1996). An unstable and highly reactive molecule, bearing an atom with an unpaired electron, that non-specifically attacks a variety of organic structures, including DNA. The interaction of ionizing radiation with water can generate hydroxyl and hydroperoxyl groups (free radicals that are potent oxidizing agents) (King et al. 2006). An atom or group of atoms with an unpaired valence electron (K. Mehta, personal communication). See ‘hydrogen radical’, ‘peroxy-radical’.
freedom from pests	Without pests (or a specific pest) in numbers or quantities that can be detected by the application of phytosanitary procedures (FAO 2006). Refer to Barclay et al. (this volume). See ‘eradication’, ‘extinction’, ‘insect-free’, ‘fly-free’, ‘pest free area’, ‘pest free field’, ‘pest free status’, ‘pest free zone’, ‘tsetse-free zone’.
free-rider	Those farms, which do not use the SIT but are located adjacent or near to farms that do apply the SIT, are called ‘free-riders’ [they get a free ride] since they benefit somewhat from the SIT (some sterile insects move into their fields from the fields in which they were released) but do not pay directly for this benefit. Refer to Whitten and Mahon (this volume). Refer also to Pearce (1992).
frugivorous	Feeding on fruit (Aluja and Norrbom 2001, White and Elson-Harris 1992, Gordh and Headrick 2001). See ‘insectivorous’, ‘nectarivorous’.
fruit stripping	Removing (stripping) all or infested fruit from fruit trees to also remove insect pests, e.g. codling moth larvae, feeding inside the fruit. This is a method of reducing a pest population during the population reduction phase. Refer to Hendrichs et al. (this volume).
full sterility	Fully sterile insects are unable to reproduce. Refer to Robinson (this volume) and Carpenter et al. (this volume). See ‘inherited sterility (IS)’, ‘partial sterility’, ’delayed sterility’, ‘sterility’, ‘induced sterility’.
fumigation	Treatment with a chemical agent that reaches the commodity wholly or primarily in a gaseous state (FAO 2006). Treating a confined area with a volatile chemical that acts as a poisonous gas (Resh and Cardé 2003, USDA 1993). The application of a fumigant to disinfest an area from pests (Bijlmakers 2008).
fusion	Synonym of ‘fertilization’. A union or combining of gametes into one cell, the zygote. See ‘fertilization’, ‘zygote’, ‘gamete’.
future value	The value that a sum of money (the present value) invested at compound interest will have in the future (Oxford 1993). See ‘present value’. ‘net present value (NPV)’, ‘discount rate’.
gamete	A germ or reproductive cell, i.e. the sperm and ovum or egg (Hoy 2003, Borders 1991). A haploid germ cell (King et al. 2006). A mature reproductive cell capable of fusing with a similar cell of opposite sex to give a zygote (Ayala and Kiger 1984). See ‘zygote’, ‘fusion’, ‘haploid’, ‘germ cell’.
gametogenesis	The formation of gametes (King et al. 2006). See ‘gamete’.
gamma irradiator	The basic components of an irradiation unit are the radiation source (pencils of either cobalt or caesium) and the associated control systems, system for transporting the product (e.g. insects) to and from the position at which irradiation occurs, and shielding to protect workers and the surrounding environment from radiation (Bakri et al., this volume). Refer to Bakri et al. (this volume), IAEA (2008b). See ‘panoramic irradiator’, ‘dry storage of radiation source’, ‘wet storage of radiation source’.
gamma radiation	The electromagnetic radiation emitted in the process of nuclear transition or particle annihilation (IAEA 1992, Borders 1991). High energy, short wavelength radiation emitted from the nuclei of atoms. Less damaging than the same dose of alpha radiation, but much more penetrating. Can be stopped by thick slabs of lead or concrete (FAO/IAEA 2009). Highly-energetic, short-wave electromagnetic radiation emitted from the nucleus of an atom. Gamma radiation energies usually range between 0.01 and 10 MeV. X-rays also occur within this energy range; they originate, however, not from the nucleus, but are generated by electron transfers in the electron sheath or by electron deceleration in matter (Bremsstrahlung). In general, alpha and beta decays and always the fission process are accompanied by gamma radiation. Gamma rays are extremely penetrative, and may best be weakened by material of high density (lead) and high atomic number (Koelzer 2008). See ‘X-ray’, ‘gamma ray’, ‘Bremsstrahlung’, ‘ionizing radiation’, ‘radiation’.
gamma ray	A highly penetrating type of nuclear radiation, similar to X-rays, except that it comes from within the nucleus of an atom, and, in general, has a shorter wavelength (FAO/IAEA 2009). Short-wavelength electromagnetic radiation of nuclear origin (Borders 1991). Electromagnetic radiation of short wavelength emitted from an atomic nucleus undergoing radioactive decay (King et al. 2006). Gamma rays have shorter wavelengths than X-rays and higher photon energies (Oxford 2006). See ‘gamma radiation’, ‘X-ray’.
gamodemes	Isolated breeding communities (MH 1997). Sympatric, and generally non-interbreeding, populations (Whitten and Mahon, this volume).
gel electrophoresis	Separation of molecules on the basis of their net electrical charge and size (Hoy 2003). The movement of the charged molecules in solution in an electrical field. The solution is generally held in a porous support medium, such as a gel made of starch, agar, or polyacrylamide. Electrophoresis is generally used to separate molecules from a mixture, based upon differences in net electrical charge and also by size or geometry of the molecules, dependent upon the characteristics of the gel matrix (King et al. 2006, Walker and Cox 1995, Kahl 1995). The negatively charged DNA molecules move at a rate that is inversely proportional to their size (Viljoen et al. 2005). See ‘acrylamide gel’, ‘polymerase chain reaction (PCR)’.
gene	The fundamental physical and functional unit of heredity. A gene is an ordered sequence of nucleotides. It encodes a specific functional product, i.e. a protein or RNA molecule. It includes regions involved in regulation of expression and regions that code for a specific functional product (Schlindwein 2006). A hereditary unit that occupies a specific position (locus) within the genome or chromosome; a unit that has one or more specific effects upon the phenotype of the organism; a unit that can mutate to various allelic forms; and a unit that recombines with other such units (King et al. 2006). A segment of DNA that codes for an RNA and/or a polypeptide molecule (Hoy 2003, Doncaster 2008).
gene flow	The exchange of genes between different populations of the same species produced by migrants, resulting in simultaneous changes in gene frequencies at many loci in the recipient gene pool (King et al. 2006). The exchange of genes between different but (usually) related populations (Schlindwein 2006, NAL 2008). The exchange of genes (in one or both directions) at a low rate between two populations, due to the dispersal of gametes or of individuals from one population to another (Ayala and Kiger 1984). The injection of new genes by migration. When the rate of immigration is high, gene flow can serve both as a source of new genetic variability and as a prime mover of evolution (Doncaster 2008). See ‘deme’, ‘gene pool’.
gene frequency	The percentage of all alleles at a given locus in a population represented by a specific allele (King et al. 2006). A measure of the proportion of an allele in a given population, equal to the number of loci at which a given allele occurs, divided by the total number of loci at which it could occur (Oxford 2006). The proportion of one particular in the total of all alleles for one genetic locus in a breeding population (NAL 2008). See ‘locus’, ‘allele’.
gene pool	All the hereditary material (genes) in a population (Doncaster 2008, Burt and Trivers 2006). The total genetic information possessed by the reproductive members of a population of sexually reproducing organisms (King et al. 2006). All of the alleles available among the reproductive members of a population from which gametes can be drawn (Schlindwein 2006). See ‘allele’, ‘gamete’.
gene-silencing	A phenomenon in which genes near certain chromosomal regions, such as centromeres or telomeres, are rendered transcriptionally inactive (King et al. 2006). Interruption or suppression of the expression of a gene at transcriptional or translational levels (NAL 2008). See ‘centromere’, ‘telomere’.
genetic control	Altering the genetic makeup of organisms to inhibit their reproduction and survival (Pedigo 2002). A method of pest control that employs genetically altered individuals which are released into the wild population, successfully copulate with members of that population, and produce sterile or inviable progeny (Gordh and Headrick 2001). A method of pest control which makes use of selected strains of the target species that possess genetic abnormalities (Bijlmakers 2008). See ‘sterile insect technique’, ‘genetically impaired female technique (GIFT)’, ‘genetic engineering’, ‘release of insects carrying a dominant lethal (RIDL)’, ‘transgenesis’.
genetic damage	Deleterious effects on genetic material. Refer to Robinson (this volume). See ‘somatic damage’.
genetic differentiation	The accumulation of differences in allelic frequencies between isolated or semi-isolated populations due to various evolutionary forces such as selection, genetic drift, gene flow, assortative mating, etc. (King et al. 2006, MH 1997). See ‘selection’, ‘genetic drift’, ‘gene flow’, ‘assortative mating’.
genetic distance	A measure of the numbers of allelic substitutions per locus that have occurred during the separate evolution of two populations or species. The distance between linked genes in terms of recombination units or map units (King et al. 2006, MH 1997). A way of measuring the amount of evolutionary divergence in two separated populations of a species by counting the number of allelic substitutions per locus that have cropped up in each population (Schlindwein 2006).
genetic diversity	A property of a community of organisms of a certain species, in which members of the community have variations in their chromosomes due to a large number of slightly dissimilar ancestors; this property makes the community in general more resistant to diseases or to changing ecological conditions (Schlindwein 2006).
genetic drift	The fluctuation of the allele frequency from one generation to the next (NAL 2008). Random change in gene frequency in a small and isolated population (MCC 1996, MH 1997). The random change in the occurrence of a particular gene in a population; genetic drift is thought to be one cause of speciation when a group of organisms is separated from its parent population (Schlindwein 2006). The alteration of gene frequencies (evolution) through chance processes alone. Genetic drift is most likely to be effective in very small populations (<100 individuals), where reduction of genetic variability lowers the capacity of a population to adapt to changes in the environment, and also tends to reduce the overall fitness of the population (Doncaster 2008). The random fluctuations of gene frequencies due to sampling errors. While drift occurs in all populations, its effects are most evident in very small populations (King et al. 2006). See ‘founder effect’, ‘fitness’, ‘colony’.
genetic engineering	The formation of new combinations of heritable material by the isolation of nucleic acid molecules, produced by whatever means outside the cell, into any virus, bacterial plasmid, or other vector system so as to allow their incorporation into a host organism in which they do not naturally occur, but in which they are capable of continued propagation (Walker and Cox 1995, Kahl 1995). The technique of removing, modifying, or adding genes to a DNA molecule (Pedigo 2002, MH 1997). Technology used to isolate genes from an organism, manipulate the genes in the laboratory, and insert them into another organism (Gordh and Headrick 2001). Directed modification of the gene complement of a living organism by such techniques as altering the DNA, substituting genetic material by means of a virus, transplanting whole nuclei, transplanting cell hybrids, etc. (NAL 2008). Gene splicing, gene manipulation, gene technology, recombinant DNA technology (Hoy 2003). The manipulation of a cell's or an organism's genetic endowment by introducing or eliminating specific genes through modern molecular biology techniques. Should result in a new capability such as production of different substances or new functions. A broad definition of genetic engineering also includes selective breeding and other means of artificial selection (Schlindwein 2006). See ‘genetic control’, ‘genetically impaired female technique (GIFT)’, ‘release of insects carrying a dominant lethal (RIDL)’, ‘transgenesis’, ‘sterile insect technique’, ‘recombination’, ‘vector’.
genetic fingerprinting	A technique (more properly termed DNA typing) that relies on the presence of simple tandem-repetitive sequences that are scattered throughout the genome. DNAs from different individuals are enzymatically cleaved and separated by size on a gel. A hybridization probe containing the core sequence is then used to label those DNA fragments that contain complementary sequences. The pattern displayed on each gel is specific for a given individual (King et al. 2006). Genetic profiling (Oxford 2006). The establishment of a DNA fingerprint (the highly specific hybridization pattern [fingerprint] generated by restriction fragment length polymorphisms (RFLP) of genomic DNA). Genomic DNA is restricted with a four- or six-base cutter restriction endonuclease. The resulting fragments are separated by gel electrophoresis, transferred to membranes and hybridized with a fingerprint probe. Since the appropriate probes detect individual-specific polymorphisms, this method can be used for the genetic identification of different individuals of one species with high certainty (Kahl 1995). Identification of chemical entities in animal tissues as indicative of the presence of specific genes (MH 1997). See ‘restriction fragment length polymorphism (RFLP)’, ‘gel electrophoresis’, ’probe’, ‘polymerase chain reaction (PCR)’.
genetic isolation	The absence of genetic exchange between populations or species as a result of geographic separation or of mechanisms that prevent reproduction (MH 1997).
genetic load	The accumulation of unfavourable or deleterious mutations in the gene pool of a specific population (Kahl 1995). Genetic burden. The decrease in fitness of a population due to deleterious mutations in the population gene pool. Specifically the average number of recessive lethal mutations, in the heterozygous state, estimated to be present in the genome of an individual in a population (Lackie and Dow 1995). See ‘gene pool’, ‘mutation’, ‘genome’, ‘fitness’.
genetic marker	A gene that enables one to detect a transgenic individual. The marker gene is located within the gene vector, usually a transposable element, and its expression indicates that the vector has inserted it into the target DNA (Resh and Cardé 2003). A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event (NAL 2008, Oxford 2006). An allele whose phenotype is recognized and which can be used to monitor the inheritance of its gene during genetic crosses between organisms with different alleles (Hoy 2003). A gene, whose phenotypic expression is usually easily discerned, used to identify an individual or a cell that carries it, or as a probe to mark a nucleus, chromosome, or locus (King et al. 2006, MH 1997). Molecular methods for making inferences about descent. These include ‘allozymes’, ‘restriction fragment length polymorphisms (RFLPs)’, ‘multilocus minisatellite’ or ‘DNA fingerprints’, ‘single locus minisatellites’ or ‘variable number of tandem repeats (VNTRs)’, ‘randomly amplified polymorphic DNA (RAPDs)’, ‘microsatellites’, and ‘mitochondrial DNA (mtDNA)’. Amongst the newer methods, minisatellites can provide a similarity index for populations, microsatellites reveal information about kinship, and mitochondrial DNA determines the maternal contribution to descent (Doncaster 2008). See ‘marker’, ‘selectable marker’, ‘transgenesis’, ‘transgenic strain’, ‘transposable element’, ‘vector’, ‘allozyme’, ‘restriction fragment length polymorphism (RFLP)’, ‘randomly amplified polymorphic DNA (RAPD)’, ‘microsatellite’, ‘mitochondrial DNA (mtDNA)’.
genetic recombination	Formation of new combinations of alleles in offspring as a result of exchange of DNA sequences between molecules (Lackie and Dow 1995, Hoy 2003). The processes by which a new genotype is formed by reassortment of genes resulting in gene combinations different from those that were present in the parents. In eukaryotes genetic recombination can occur by chromosome assortment, intrachromosomal recombination, or non-reciprocal interchromosomal recombination. Intrachromosomal recombination occurs by crossing over (Oxford 2006, King et al. 2006, Kahl 1995, Schlindwein 2006). The formation of new combinations of alleles, typically during meiosis. This may include the process by which DNA molecules are broken and the fragments rejoined into new combinations (Burt and Trivers 2006). The genetic exchange between two homologous chromosomes leading to the occurrence of recombinants. In case of genetic sexing, it refers primarily to recombination in males resulting, in the next generation, in a reversal of the sexing system, i.e. recombinants are either wild-type females or mutant males (FAO/IAEA/USDA 2003). Refer to Franz (this volume). See ‘recombination’, ‘male recombination’, ‘crossing-over’, ‘genetic engineering’, ‘meiosis’, ‘genetic sexing’.
genetic sexing	Also ‘genetic sexing system (GSS)’. Genetic method to produce unisexual progeny. See ‘sex separation’.
genetic sterility	Sterility caused through alteration in the genetic material. See ‘cytoplasmic incompatibility’, ‘refractory’, ‘genetic engineering’, ‘genetically impaired female technique (GIFT)’, ‘release of insects carrying a dominant lethal (RIDL)’.
genetic transformation	A stable, heritable change in genotype caused by the incorporation of foreign DNA into the genome (Resh and Cardé 2003). A change in the genetic structure of an organism via genetic engineering (Pedigo 2002). Change brought about to an organism’s genetic composition by unidirectional transfer and incorporation of foreign DNA into prokaryotic or eukaryotic cells by recombination of part or all of that DNA into the cell’s genome (NAL 2008). See ‘genotype’, ‘genome’, ‘genetic engineering’.
genetic variation	Genetic variation of a population is the presence of genotypically different individuals.
genetically impaired female technique (GIFT)	System combines chromosome rearrangements with eye colour and other mutations, such that mass-reared females are killed or debilitated. The mutations and rearrangements are inherited in the offspring of field females mated by released males, causing genetic death, leading to population collapse (Foster et al. 1993). Refer to Klassen (this volume). See ‘genetic control’, ‘sterile insect technique’.
genetically modified organism (GMO)	Food or plants with a genetic composition that has been altered through genetic engineering (Collin 2001). An organism whose genes have been deliberately manipulated (Bijlmakers 2008). Living modified organism (LMO) = Any living organism that possesses a novel combination of genetic material obtained through the use of modern biotechnology (FAO 2006). See ‘biosafety’, ‘biodiversity’, ‘genetic engineering’, ‘organism’.
genetics revolution	The recent rapid scientific developments in genetics, gene technology and biotechnology – genetically modified organisms (GMOs), genetic engineering, description of the genomes of humans and other organisms, treatment of diseases, cloning of animals, etc. Refer to Whitten and Mahon (this volume), Morgan (2005), TIME (1999). See ‘genome’, ‘genetically modified organism (GMO)’, ‘genetic engineering’.
genitalia	Genitalia are external components of the reproductive system (Gordh and Headrick 2001). Copulatory organs of an animal (Hutchinson 1998). See ‘copulation’.
genome	The entire nucleotide sequence of an organism, including the entire set of genes (Resh and Cardé 2003). The total complement of DNA in an organism (Hoy 2003). The full genome of an individual is borne by a single representative of each of all the chromosome pairs in a nucleus (Doncaster 2008). All the genetic material in the chromosomes of a particular organism; its size is generally given as its total number of base pairs (Schlindwein 2006). See ‘gene’, ‘chromosome’.
genotype	All or part of the genetic composition of an individual or population (Resh and Cardé 2003, Hoy 2003). The genetic constitution of an organism, cell, individual or taxon, as distinct from its physical appearance, i.e. phenotype (NAL 2008). The hereditary constitution of an individual, or of particular nuclei within its cells (Schlindwein 2006). See ‘phenotype’.
geographic information systems (GIS)	Computer-based systems capable of capturing, cleaning (checking for errors and gaps), integrating, storing, retrieving, analysing, and displaying spatial data. GIS incorporate spatial data (geographical features) in the form of geographical coverages (maps), and descriptive data (attributes) in the form of relational databases linked to the mapped features. GIS have the ability to analyse data based on their location and spatial characteristics (Cox and Vreysen, this volume). Computer-based information systems for gathering, storing, integrating, analysing, and displaying geospatial information, e.g. insect densities across a field (Pedigo 2002, Gordh and Headrick 2001, NAL 2008). See ‘database’. ‘spatial analysis’, ‘kriging’.
geographic range	The geographic area or region over which a species is distributed (MH 1997). See ‘home range’, ‘range fragmentation’.
geo-reference	Geo-referencing – The practice of establishing the relationship between coordinates on a map or image with the specific real-world coordinates (a geographic location) (NAL 2008). Examples: attaching geographic location information to insect traps in the field, or to data on pest population density or pest infestation. Refer to Leak et al. (2008). See ‘Global Positioning System (GPS)’, ‘geographic information systems (GIS)’.
geostatistics	A body of analytical techniques for the study of spatial pattern. There are two interrelated components to geostatistics: variography and spatial interpolation (kriging) (Glossary 2008). See ‘kriging’.
germ cells	Cells that are ancestors of oocytes (Resh and Cardé 2003). Early-stage undifferentiated reproductive cells in the ovariole which are destined to become ova or spermatozoa (Gordh and Headrick 2001). The male and female reproductive cells (Walker and Cox 1995). See ‘ovariole’, ‘oocyte’, ‘spermatogenesis’.
gestation	The period from egg fertilization to oviposition during which the embryo matures in the body of the female parent (Gordh and Headrick 2001), or in the case of insects that reproduce by adenotrophic viviparity, e.g. tsetse flies Glossina spp., the period from egg fertilization to larviposition. See ‘adenotrophic viviparity’, ‘fertilization’, ‘larviposition’, ‘larviparous’, ‘viviparous’.
ginger root oil	See ‘aromatherapy’, ‘citrus peel oil’.
Global Positioning System (GPS)	The GPS is useful for mapping spatial features. The basis of the GPS is a constellation of 24 satellites which act as reference points, with each satellite transmitting a radio signal in the form of pseudo-random code. On the ground, GPS receivers use this code to determine distances to each satellite (‘ranging’), and calculate their position and altitude by ‘trilaterating’ signals from a number of satellites (Cox and Vreysen, this volume). A technology that uses the position of satellites to provide precise location coordinates on the earth’s surface (NAL 2008). In applying the SIT, the GPS is used to geo-reference insect traps, and to guide the flight path of aircraft releasing sterile insects. Refer to Vreysen (this volume), Dowell et al. (this volume). See ‘geo-reference’, ‘aerial release’, ‘geographic information systems (GIS)’.
globalization	The worldwide integration of markets for goods, services and capital (NAL 2008).
gonadotrophic cycle	Also ‘gonadotropic cycle’, referring to cyclical gonadal functions, e.g. periodic production of an egg in the ovary of tsetse flies Glossina spp. A ‘gonad’ is an animal organ, e.g. ovary, that produces gametes. Refer to Vreysen (this volume), Saunders (1972).
gonial cells	Primordial sex cells (gonia), e.g. oogonia and spermatogonia (MH 1997).
gossyplure	The sex pheromone of the female pink bollworm Pectinophora gossypiella (Saunders) as well as the synthetic sex attractant used to elicit attraction of male bollworms (NAL 2008). Refer to Mangan (this volume), Bloem et al. (this volume). See ‘sex pheromone’, ‘attraction’, ‘ceralure’, ‘cuelure’, ‘disparlure’, ‘hexalure’, ‘propylure’, ‘swormlure’, ‘trimedlure’.
gravid	Pertaining to female animals when carrying young or eggs (MH 1997).
green fluorescent protein (GFP)	Sterile insects for release are usually marked with a fluorescent powder; transgenic techniques could enable them to be marked with a fluorescent protein. Using a genetic marker for released insects requires that the marker be dominant, and that it can be monitored even in dead adults, as insects are usually dead when removed from traps. There are currently two fluorescent protein markers available to accomplish this, i.e. green fluorescent protein (GFP) and red fluorescent protein (DsRed) (Robinson and Hendrichs, this volume). A protein produced by the jellyfish Aequorea victoria. It produces a green emission when it is excited by blue light. GFP provides an excellent means for cytologically localizing the product from any foreign gene that can be spliced to the GFP open reading frame. The fused protein is often fully functional, and can be localized to its normal site in the cell by its green fluorescence (King et al. 2006, Oxford 2006). See ‘marking’, ‘red fluorescent protein (DsRed)’, ‘genetic marker’.
gross domestic product (GDP)	The value of the total final output of goods and services produced inside a country during a given year (NAL 2008).
ground release	Release of sterile insects from the ground. Refer to Dowell et al. (section 5.2.) (this volume). See ‘release’, ‘aerial release’, ‘static release’.
ground spray	Application of a pesticide spray from the ground. Refer to Nagel and Peveling (this volume), Mangan (this volume). See ‘aerial spray’, ‘chemical control’.
growth model	Mathematical model or equation that describes the growth in number of individuals in a population over time. Refer to Barclay (this volume), Barclay et al. (this volume). A ‘growth curve’ is a graphed version of a growth model, showing changes over time in the population size (Gordh and Headrick 2001).
Haisch Index	An index to measure the sexual competitiveness of sterile insects in the field. Refer to Itô and Yamamura (this volume), Haisch (1970). See ‘competitiveness’. ‘mating competitiveness’.
Haldane’s Rule	There is preferential sterility or inviability in the hybrids of the heterogametic sex. This means that, in Lepidoptera where the female is heterogametic, the major hybrid effects would be seen in the resulting female hybrids, whereas in Diptera where the male is heterogametic, the F1 males will be more affected (Robinson, this volume). When one sex is absent, rare, or sterile, in the offspring of two different animal races or species, that sex is the heterogametic sex. The rule may be explained by the non-harmonious interaction of X- and Y-linked fertility genes in the hybrid (King et al. 2006). See ‘heterogametic’.
Hale-Malthusian	The basic mathematical model to describe the exponential increase of populations (Itô and Yamamura, this volume). See ‘logistic model’, ‘population model’.
Hamada method	One of the mark-recapture methods to estimate the population density in the field. The ‘Hamada method’ is a modification of the ‘Jackson positive method’; the bias is reduced in this method. It is assumed that the number of wild individuals, excluding marked individuals, is kept constant during the capture period (Itô and Yamamura, this volume). See ‘Itô method’, ‘Jackson positive method’, ‘Jackson negative method’, ‘Jolly-Seber method’, ‘Petersen method’, ‘Yamamura method’.
haplodiploidy	A genetic system found in some animals, e.g. honey bee, in which males develop from unfertilized eggs and are haploid, whereas the females develop from fertilized eggs and are diploid (King et al. 2006, Burt and Trivers 2006) See ‘haploid’. ‘diploid’.
haploid	Condition in which a cell or organism has a single genome or a single set of homologous chromosomes (King et al. 2006, Oxford 2006, Hoy 2003). See ‘diploid’, ‘polyploid’, ‘gamete’.
haplotype	The symbolic representation of a specific combination of linked alleles in a cluster of related genes. This term is a contraction of haploid genotype (King et al. 2006). A set of genes located on a single chromosome; the term is used also to denote the characteristics dependent on those genes (Oxford 2006). A set of closely linked genetic markers present on one chromosome which tend to be inherited together (Schlindwein 2006). See ‘haploid’, ‘genotype’.
Hardy-Weinberg theorem	The Hardy-Weinberg law: The allelic (gene) and genotype frequencies in an infinitely large interbreeding population remain constant from generation to generation if mating is at random and there is no selection, migration or mutation (Doncaster 2008, King et al. 2006). A principle by which genotypic frequencies can be predicted on the basis of gene frequencies, under the assumption of random mating (Ayala and Kiger 1984). Hardy-Weinberg equilibrium: An equilibrium of genotypes achieved in populations of infinite size in which there is no migration, selection, or mutation after at least one generation of panmictic mating (Hoy 2003). See ‘evolutionary genetics’, ‘population genetics’.
Heavily Indebted Poor Countries (HIPC)	Countries in the world listed as Heavily Indebted Poor Countries by the World Bank and the International Monetary Fund (WB 2008).
helicopter	Aircraft with horizontally rotating blades. See ‘fixed-wing aircraft’.
hemimetabolous	Refers to those insects in which metamorphosis is simple and gradual; incomplete metamorphosis. Each insect gradually acquires wings during a period of growth interrupted by several moults. Immature forms are called nymphs, if terrestrial, naiads if aquatic, and resemble the adult form (King et al. 2001, Resh and Cardé 2003). See ‘holometablous’.
heterochromatin	Regions of the genome that are highly condensed and (mostly) transcriptionally inactive throughout the cell cycle (Burt and Trivers 2006, Lewin 1985). Chromosomal material that, unlike euchromatin, shows maximal condensation in nuclei during interphase (King et al. 2006, Oxford 2006). Composed of non-coding repetitive DNA (Schlindwein 2006, Hoy 2003).
heterogametic	A sex that produces gametes containing unlike sex chromosomes. Many males are XY and thus heterogametic. Lepidopteran females are the heterogametic sex (Hoy 2003). See ‘homogametic’.
heterogeneity	Differing in kind, character or content, as in a heterogeneous population (Oxford 2008). Contrast with ‘homogeneity’ – being uniform in kind.
heterosis	The greater vigour in terms of growth, survival, and fertility of hybrids, usually from crosses between highly inbred lines. Heterosis is always associated with increased heterozygosity (King et al. 2006). Hybrid vigour (Hoy 2003). Superiority of the heterozygote over the homozygotes (Ayala and Kiger 1984). See ‘hybrid vigour’, ‘hybrid’, ‘hybridization’, ‘underdominance’.
heterozygous	Having genetically different alleles at a particular locus on homologous chromosomes (Walker and Cox 1995, Lewin 1985, Ayala and Kiger 1984, Schlindwein 2006). A measure of genetic variation in a population estimated by a single locus or an average over several loci (Hoy 2003). See ‘homozygous’.
hexalure	A synthetic sex attractant that is used to control the pink bollworm Pectinophora gossypiella (Saunders) (Coombs and Hall 1998; Mangan, this volume). See ‘sex pheromone’, ‘attraction’, ‘ceralure’, ‘cuelure’, ‘disparlure’, ‘gossyplure’, ‘propylure’, ‘swormlure’, ‘trimedlure’.
High Efficiency Particulate Air (HEPA)	Type of air filter that can remove very small particles from the air, and thus used to provide very clean air for a rearing facility. HEPA filters can remove at least 99.97% of airborne particles 0.3 microns in diameter (Wikipedia 2008). Refer to Dowell et al. (this volume), Parker (this volume), Dyck (2010).
holokinetic	Chromosome with diffuse kinetic activity due to the presence of non-localized (diffuse) instead of localized centromere (Robinson, this volume). See ‘centromere’, ‘acentric’, ‘dicentric’, ‘monocentric’, ‘monokinetic’.
holometabolous	Refers to those insects in which larval and pupal stages are interposed between the embryo and the adult. Metamorphosis is complete, with four very different life stages — egg, larva, pupa, adult (King et al. 2006, Resh and Cardé 2003). See ‘hemimetabolous’.
home range	The total area occupied over the years by a group of animals or an individual animal (Allaby 1994). The physical area of an organism’s normal activity (MH 1997, Scott 1996). Native range = The ecosystem that a species inhabits (Wikipedia 2008). See ‘geographic range’, ‘range fragmentation’.
homogametic	A sex that produces gametes with only one kind of sex chromosome. The females of many insects are XX and thus homogametic (Hoy 2003). See ‘heterogametic’.
homogeneous distribution	The even or uniform distribution (arrangement, pattern) of individuals of a species in its habitat (Allaby 1994). Contrasts with clumped distribution. See ‘distribution’, ‘clumped distribution’, ‘continuous distribution’, ‘fragmented distribution’, ‘island distribution’.
homolog	Also spelled ‘homologue’. One of a pair, or larger set, of chromosomes having the same overall genetic composition and sequence (Doncaster 2008). Homologs are chromosomes carrying the same genetic loci (Lewin 1985). See ‘homologous chromosomes’.
homologous chromosomes	Two or more identical chromosomes (Hoy 2003). A pair of chromosomes containing the same linear gene sequences, each derived from one parent (Schlindwein 2006). See ‘homolog’.
homoplasy	Phenomena that lead to similarities in character states for reasons other than inheritance from a common ancestor, including convergence, parallelism, and reversal (Hoy 2003). Appearance of similar structures in organisms not inherited from a common ancestor or developed from a common anlage. Indication for the universal mechanisms of evolution (Schlindwein 2006).
homozygous	Having genetically identical alleles at a particular locus on homologous chromosomes (Walker and Cox 1995). The presence of the same alleles at one or more loci (Schlindwein 2006). Having two identical alleles of a particular gene on both homologous chromosomes (Hoy 2003, Doncaster 2008). See ‘heterozygous’, ‘homologous chromosomes’, ‘allele’.
host	An organism which harbours a parasite (Allaby 1994). An organism on or in which a parasite lives; a plant on which an insect feeds (MH 1997, Pedigo 2002, Coombs and Hall 1998, Cohen 2004). A parasite lives permanently, or for part of its life cycle, on or in the host, where it feeds and reproduces (Scott 1996). Any plant or animal attacked by a pest or a parasite (USDA 1993, Hill 1997). See ‘host-parasitoid model’, ‘parasitism’, ‘parasitoid’.
host range	The variety of different host species that provide nourishment, shelter or are otherwise associated with a specific parasite or symbionts (NAL 2008). The group of species that can be attacked by a given parasite (King et al. 2006). The spectrum of host organisms that can be infected by a specified infectious agent or parasite (Oxford 2006). Species capable, under natural conditions, of sustaining a specific pest or other organism (FAO 2006). See ‘host’.
host specificity	The degree to which parasites of plants or animals show specificity for a host varies – strictly one host, or having an alternate host, or having a secondary host (Scott 1996). See ‘host’.
host-parasitoid model	See ‘Nicholson-Bailey model’, ‘model’, ‘host’, ‘parasitoid’, ‘parasitism’.
host-plant resistance	In the context of integrated pest management (IPM), host-plant resistance to pests refers to the relative amount of heritable qualities possessed by a plant that reduces the degree of damage done to the plant by a pest (Pedigo 2002, Gordh and Headrick 2001). See ‘host’, ‘resistance management’.
host-vector	Relationship between an animal (or plant) host and an insect vector of a disease. See ‘host’, ‘vector’.
hot spot	A location or area with an unusually high insect density (Vreysen, this volume). Untreated or inadequately treated refugium or microhabitat unusually favourable for the pest, i.e. ‘hot spot’, from which recruits could come to reinfest cleared areas (Klassen, this volume).
human African trypanosomosis (HAT)	The human disease trypanosomosis (trypanosomiasis) (sleeping sickness) found in sub-Saharan Africa caused by trypanosomes and transmitted by tsetse flies. Refer to Pentreath and Kennedy (2004), Feldmann et al. (this volume). See ‘African animal trypanosomosis (AAT)’, ‘trypanosomosis’.
hybrid	An offspring from genetically dissimilar parents, even different species. A heterozygote (King et al. 2006). A cross-bred, heterozygote organism or cell, an individual from any cross involving parents of differing genotypes. Offspring of unlike parents (Schlindwein 2006).
hybrid sterility	The failure of hybrids between different species to produce viable offspring (King et al. 2006). Reduction or suppression of the reproductive capacity in hybrid organisms (Ayala and Kiger 1984). See ‘hybrid’.
hybrid vigour	The increase in size or rate of growth or fertility or survival associated with increased heterozygosity (Doncaster 2008). See ‘heterosis’, ‘hybrid’, ‘hybridization’, ‘heterozygous’.
hybridization	The mating of individuals belonging to genetically disparate populations or to different species. The mating of any two unlike genotypes or phenotypes (King et al. 2006). The process of joining two complementary strands of DNA, or one each of DNA and RNA, to form a double-stranded molecule (Schlindwein 2006). See ‘hybrid’.
hydrogen radical	Hydrogen atom which has lost one valence electron (K. Mehta, personal communication). See ‘free radical’, ‘peroxy-radical’.
hydroponics	The growing of plants in aqueous chemical solutions (Bijlmakers 2008).
hypergeometric probability distribution	Similar to a binomial distribution, but while the binomial distribution assumes sampling with replacement, the hypergeometric probability distribution assumes sampling without replacement. For large populations, the two give very similar probabilities, and for infinite populations, there is no difference between the two. However, for small populations and samples that are a significant proportion of the total population, they differ noticeably (H. Barclay, personal communication; Everitt 2006). See ‘binomial distribution’, ‘Poisson distribution’, ‘Poisson binomial distribution’, ‘negative binomial distribution’, ‘probability model’.
hyperparasitoid	A parasitoid that lives within or off of another parasitoid (Grimaldi and Engel 2005, Hill 1997). See ‘parasitoid’.
hypoxia	An oxygen-reduced environment. A deficiency of oxygen reaching the tissues of the body (Bakri et al., this volume; Oxford 2008). Clinical manifestation of respiratory distress consisting of a relatively complete absence of oxygen (NAL 2008). See ‘anoxia’, ‘radiation environment’.
immigration	Movement of individuals into a population or area (Collin 2001, Hill 1997). See ‘migration’, ‘emigration’.
immunization	Rendering an organism immune to a specific communicable disease (MH 1997). Deliberate stimulation of the host’s immune response (NAL 2008).
impact	Having a marked, forceful or strong effect, influence or consequence on somebody or something (Oxford 2008, Webster 2008).
in utero	Within the uterus (MH 1997). Biological process, growth or development of organisms in a uterus. In insects, the uterus is the enlarged portion of the median oviduct in viviparous insects; sometimes the enlarged portion of the bursa copulatrix at the junction of the oviducts (Gordh and Headrick 2001).
inbreeding	Breeding of closely related individuals (MH 1997). The crossing of closely related plants or animals (King et al. 2006). The mating of genetically related individuals (Schlindwein 2006, NAL 2008). Pairing and reproduction between individuals that are more closely related than average pairs selected at random from the population (Scott 1996). See ‘inbreeding coefficient’.
inbreeding coefficient	Probability of identity by descent (Krafsur, this volume). A measure of the rate of inbreeding or the degree to which an individual is inbred (MH 1997). The probability that two allelic genes united in a zygote are both descended from a gene found in an ancestor common to both parents. Also, the proportion of loci at which an individual is homozygous (King et al. 2006). The probability of homozygosity by descent (having common ancestors). The probability that a zygote obtains copies of the same ancestral gene from both its parents because they are related (Schlindwein 2006, NAL 2008). The probability that two alleles at the same locus in an individual are copies of the same gene, i.e. identical by descent (Scott 1996). See ‘inbreeding’.
indirect benefits	Various social and economic benefits from pest management activities received indirectly by agricultural producers and the local community, e.g. increase in agricultural exports; increase in yield through reduced secondary pest outbreaks; better human nutrition; savings in medical costs and even deaths, and in public health and environmental costs, through reduced use of pesticides; greater protection of beehives; and new jobs created in agriculture and related industries (Enkerlin, this volume). See ‘benefit/cost analysis (BCA)’, ‘direct benefits’.
indirect sampling	Sampling insects indirectly by monitoring host organisms, e.g. surveillance of myiasis cases in animals, disease transmission, and crop damage (Vreysen, this volume). See ‘sampling’, ‘direct sampling’.
induced sterility	Sterility caused by physical, chemical or biological intervention (A.S. Robinson, personal communication). Refer to Robinson (this volume), Carpenter et al. (this volume), Vreysen (this volume). See ‘sterility’, ‘inherited sterility (IS)’, ‘full sterility’.
infecundity	Inability to produce eggs. Refer to Klassen (this volume). See ‘fecundity’.
infrared	Electromagnetic radiation with wavelengths longer than that of red light but shorter than radio waves, i.e. radiation in the wavelength range 0.7 micrometre to 1 millimetre (Isaacs 2000).
inherited sterility (IS)	Sterility caused by inheritable chromosome changes (A.S. Robinson, personal communication). Refer to Carpenter et al. (this volume). See ‘partial sterility’, ’delayed sterility’, ‘full sterility’, ‘induced sterility’, ‘sterility’.
inoculative release	The release of relatively small numbers of natural enemies that are expected to colonize, reproduce, and spread naturally throughout an area (Weeden et al. 2000). Contrast with ‘inundative release’. See ‘inundative release’.
insect growth regulator (IGR)	A category of insecticidal compounds which function as juvenile hormone analogues that interrupt growth and development or act as chitin synthesis inhibitors. IGRs display low mammalian toxicity and are effective only on immature insects (Gordh and Headrick 2001). Substance effective in upsetting or modifying normal insect growth processes (Pedigo 2002). See ‘juvenile hormone (JH)’, ‘chitin synthesis inhibitor’.
insect-free	Referring to an area or product in which a specific insect pest does not occur as demonstrated by scientific evidence and in which, where appropriate, this condition is being officially maintained. See ‘eradication’, ‘extinction’, ‘freedom from pests’, ‘fly-free’, ‘pest free area’, ‘pest free field’, ‘pest free status’, ‘pest free zone’, ‘tsetse-free zone’.
insecticide residue	The insecticide that remains on or in food after it has been applied to a food crop. See ‘pesticide residue’, ‘residue’.
insecticide resistance	Genetically inherited ability to withstand doses of insecticide which would kill individuals from strains whose ancestors had not been exposed to the insecticide (Weeden et al. 2000). The ability of an organism to survive doses of a toxin that would normally be expected to be fatal (Coombs and Hall 1998). The ability of an insect population to withstand and survive the poisonous and toxic effects of an insecticide (Bijlmakers 2008, Hill 1997). The ability of strains of insects to survive normally lethal doses of insecticide, the ability having resulted from selection of tolerant individuals in populations exposed to the toxicant for several generations (Pfadt 1962). See ‘resistance management’, ‘pesticide resistance’.
insectivorous	Insect-eating; pertaining to organisms subsisting on insects (Gordh and Headrick 2001). Feeding on a diet of insects (MH 1997). See ‘nectarivorous’, ‘frugivorous’.
insemination	Fertilizing with semen (Gordh and Headrick 2001). See ‘fertilization’, ‘copulation’.
inspection	Official visual examination of plants, plant products or other regulated articles to determine if pests are present and/or to determine compliance with phytosanitary regulations (FAO 2006).
integrated control	Control of pests that emphasizes selective use of insecticides so as to conserve natural enemies in the agroecosystem (Pedigo 2002). An approach to pest control which embraces techniques including biological control, chemical control, cultural control (Gordh and Headrick 2001).
integrated pest management (IPM)	The careful consideration of all available pest control techniques and subsequent integration of appropriate measures that discourage the development of pest populations and keep pesticides and other interventions to levels that are economically justified and reduce or minimize risks to human health and the environment. IPM emphasizes the growth of a healthy crop with the least possible disruption in agroecosystems and encourages natural pest control mechanisms (FAO 2003, Hendrichs et al. 2007). A programmatic approach to pest control that has as its foundation the use of biological control methods, plant breeding, and the judicious application of pesticides, especially selective pesticides (Gordh and Headrick 2001). A system for controlling pests that is based on the combined use of a range of different methods (e.g. biopesticides, biocontrol agents, mating disruption, trapping, crop rotation, etc.) in order to minimize the use of chemical pesticides (Coombs and Hall 1998). For a compendium of IPM definitions, see: http://ipmnet.org/IPMdefinitions/home.html
intellectual property rights (IPR)	The rights granted by a government authority for certain products of intellectual effort and ingenuity (Webster 2008). Refers to creations of the mind. Under intellectual property law, the holder of an abstract ‘property’ has certain exclusive rights to the creative work (Wikipedia 2008).
interbreed	To breed by crossing different stocks, varieties, or species of animals or plants (IDIDAS 2008). To breed with an animal of a different race or species (Oxford 2008). Breed animals or plants using parents of different races and varieties (Webster 2008). See ‘hybridization’, ‘hybrid’.
internal rate of return (IRR)	This concept explicitly takes into account the timing of the cash flows from a project. It is the discount rate which makes the net present value of a project equal to zero (Pearce 1992). If the internal rate of return exceeds the market rate of interest, then the project is profitable. The internal rate of return is usually considered less reliable than the actual net present value as a means of appraising a project (Oxford 1993). Another way of thinking of the internal rate of return is that it represents the average rate of return for a project over its life, taking into account negative returns in early years of investment and positive rates in later years. See ‘rate of return’, ‘economic return’, ‘net return’, ‘discount rate’, ‘net present value’, ‘present value’, ‘payback’, ‘cost recovery’.
interphase	The period between succeeding mitoses (King et al. 2006). The state of a eukaryotic cell when not undergoing mitosis or meiosis (Oxford 2006). The stage of the cell or nucleus when it is not in mitosis, hence comprising most of the cell cycle (Lackie and Dow 1995). The period in the cell cycle when DNA is replicated in the nucleus (Schlindwein 2006, Hoy 2003). See ‘mitosis’, ‘meiosis’, ‘prophase’, ‘metaphase’, ‘anaphase’, ‘telophase’.
intervention	Taking action (intervening) in some situation, e.g. a pest infestation, to change the course of events, e.g. to manage the pest.
intervention block	An area (block) of land or habitat demarcated as the area for intervention action (treatment) in area-wide integrated pest management. A block contains a core area, where the commodity to be protected, e.g. crop, is located, and an edge area next to or around the core area. Refer to Hendrichs et al. (this volume).
intrinsic rate of increase	The rate at which a population is increasing in number, measured by deducting the instantaneous death rate from the instantaneous birth rate (Allaby 1994). The fraction by which a population is growing at any instant in time (Gordh and Headrick 2001). Inherent rate at which a population increases in number, i.e. based on the basic biological characteristics of the species.
introduction	In the context of classical biological control, introduction refers to the importation of a natural enemy from a foreign country or continent, usually to control a pest also of foreign origin (Weeden et al. 2000). However, in the context of pest introduction, see ‘pest introduction’, ‘invasive species’, ‘entry’.
inundative release	The release of large numbers of mass-produced biological control agents or beneficial organisms with the expectation of achieving a rapid effect (FAO 2006). A method of periodic introduction [augmentation] of biotic agents which is analogous to insecticide treatment in that a greater amount of the liberated material is used than is actually effective, repetition may be necessary, and the effect is more or less immediate (Coppel and Mertins 1977, Daly et al. 1998, Weeden et al. 2000, Coombs and Hall 1998). Contrast with ‘inoculative release’. See ‘sterile insect technique’, ‘inoculative release’.
invasion	The expansion of a species into an area not previously occupied by it (Wikipedia 2008). Arrival of large numbers of pests in an area (Collein 2001). See ‘entry’, ‘pest introduction’, ‘invasive species’, ‘exotic species’, ‘immigration’, ‘reinvasion’.
invasive species	Species that tend to spread beyond their native range to new areas. Invasive species are those plants, animals, and microbes not native to a region which, when introduced either accidentally or intentionally, cause economic or environmental harm or harm to human health (NAL 2008). A subset of plants or animals that are introduced to an area, survive, and reproduce, and cause harm economically or environmentally within the new area of introduction (Wikipedia 2008). See ‘entry’, ‘pest introduction’, ‘exotic species’, ‘prevention’, ‘home range’, ‘pest establishment’.
inversely density-dependent	Refers to mortality factors or processes in the environment which destroy a decreasing percentage of the subject population as its numerical density increases (Coppel and Mertins 1977). See ‘density-dependence’.
inversion	See ‘chromosomal inversion’, ‘paracentric inversion’, ‘pericentric inversion’. See ‘temperature inversion’.
ionizing radiation	Charged [or uncharged] particles and electromagnetic waves that as a result of physical interaction create ions by either primary or secondary processes (FAO 2006). Certain radiations, in their passage through matter, are capable of causing ionization, i.e. they can knock electrons out of atoms or molecules or create ions either directly or indirectly (Porteous 1996, IAEA 1992, Borders 1991). Any radiation capable of displacing electrons from atoms or molecules, thereby producing ions. Some examples are alpha, beta, gamma, X-rays, neutrons (FAO/IAEA 2009). Any radiation which directly or indirectly ionizes, e.g. alpha, beta, gamma, neutron radiation (Koelzer 2008). See ‘gamma radiation’, ‘radiation’.
irradiation	Treatment with any type of ionizing radiation (FAO 2006). Exposure to some form of radiation (FAO/IAEA 2009, Borders 1991). See ‘ionizing radiation’, ‘gamma radiation’, ‘radiation exposure’.
irradiation protocol	Documented procedure for irradiating a sample, e.g. an insect canister, that is based on experimental results and consideration of all factors that could affect the irradiation process (K. Mehta, personal communication). See ‘irradiation’.
irradiator	See ‘gamma irradiator’, ‘panoramic irradiator’, ‘wet storage of radiation source’, ‘dry storage of radiation source’.
irritability	The capacity of an organism to receive external stimulus and respond to that stimulus (Gordh and Headrick 2001). A condition or quality of being excitable; the power of responding to a stimulus (MH 1997). A behavioural parameter of importance in insect rearing. A loss of irritability can mean a loss of predator-evasion behaviour when reared insects are released in the field, hence the development of a quality control test (startle test). Refer to Calkins and Parker (this volume). See ‘startle test’.
island distribution	The distribution of an insect population confined to an island surrounded by water. Refer to Hendrichs et al. (this volume). See ‘distribution’, ‘clumped distribution’, ‘homogeneous distribution’, ‘continuous distribution’, ‘fragmented distribution’.
ISO/ASTM standard	An international reference standard created by the International Organization for Standardization (ISO) and the American Society for Testing and Materials International (ASTM). These two organizations serve as an open forum for the development of international standards. Note the standard entitled “Guide for dosimetry for sterile insects release programs” ISO/ASTM 51940:2004.
isocline	A line representing all points satisfying a derivative equated to zero in a differential equation, or all points representing no change in a difference equation. If there are two or more isoclines, then the points where they intersect represent equilibria of the system (H. Barclay, personal communication).
isodose curves	Lines or surfaces of constant absorbed dose through a specified medium (Borders 1991, ISO/ASTM). Geometric place for all points where the dose variable has the same value (Koelzer 2008). Refer to Bakri et al. (this volume).
isofemale strain	A strain of insects based on the progeny of a single mated pair (Krafsur, this volume). A genetic lineage that began with a single inseminated female (King et al. 2006).
isolated infestation	A pest infestation that is localized and separated from other sites of infestation by the same species.
isolation index (ISI)	A measure of mating compatibility between two strains/populations, and is a quality control parameter. Refer to Calkins and Parker (Box 1) (this volume), (FAO/IAEA/USDA 2003). See ‘relative isolation index (RII)’, ‘female relative performance index (FRPI)’, ‘male relative performance index (MRPI)’, ‘assortative mating’.
isotope	One of two or more forms of an element differing from each other in atomic weight, and in nuclear but not chemical properties. Each of two or more forms of the same element that contain equal numbers of protons [same atomic number] but different numbers of neutrons [different mass number or atomic weight] in their nuclei (FAO/IAEA 2009, Oxford 2008, Borders 1991). Atoms of the same atomic number, i.e. the same chemical element, however with a different nucleon number (Koelzer 2008).
isotropic	Having the same properties in all directions. Regarding radiation emission, this indicates equal emission in all directions from a point source (Borders 1991).
isozyme	Synonym for ‘isoenzyme’ (Oxford 2006). Enzymes that act on a common substrate (Krafsur, this volume). Multiple forms of an enzyme. These are not isomers, as a rule, but distinct protein molecules with unique metabolic functions (Gordh and Headrick 2001). Isozymes are complex proteins made up of paired polypeptide subunits. Isozymes often have different isoelectric points, and therefore can be separated by electrophoresis (King et al. 2006). Isozymes differ from each other in their substrate affinity, in their activity, or in their regulatory properties (Hoy 2003). Multiple forms of an enzyme whose synthesis is controlled by more than one gene (Schlindwein 2006).
Itô method	One of the mark-recapture methods to estimate the population density in the field. The ‘Itô method’ is a modification of the ‘Jackson positive method’; the bias is reduced in this method. It is assumed that the total number of individuals, including wild and marked individuals, is kept constant during the capture period (Itô and Yamamura, this volume). See ‘Hamada method’, ‘Jackson positive method’, ‘Jackson negative method’, ‘Jolly-Seber method’, ‘Petersen method’, ‘Yamamura method’.
Jackson negative method	One of the mark-recapture methods to estimate the population density in the field. The ‘Jackson negative method’ is based on multiple-release single-recapture data. Marked individuals are released on several occasions with different markings, and thereafter a single random catch is made on day 0 (Itô and Yamamura, this volume). See ‘Hamada method’, ‘Itô method’, ‘Jackson positive method’, ‘Jolly-Seber method’, ‘Petersen method’, ‘Yamamura method’.
Jackson positive method	One of the mark-recapture methods to estimate the population density in the field. The density and survival rate are estimated for the population by a single release and multiple recapture censuses. It is assumed that the total number of individuals, including wild and marked individuals, is kept constant during the capture period. Recaptured individuals should be returned to the original population (Itô and Yamamura, this volume). See ‘Hamada method’, ‘Itô method’, ‘Jackson negative method’, ‘Jolly-Seber method’, ‘Petersen method’, ‘Yamamura method’.
Jackson trap	A delta-shaped (triangular) insect trap with a sticky cardboard insert, usually used with a parapheromone lure to attract and capture male fruit flies (IAEA 2003). See ‘attractive device’, ‘delta trap’, ‘pheromone trap’, ‘sticky trap’, ‘trap’, ‘wing trap’, ‘parapheromone’, ‘attraction’.
Jolly-Seber method	One of the mark-recapture methods to estimate the population density in the field. The ‘Jolly-Seber method’ is applicable where the population density is changing because of mortality, emigration, birth, and immigration. Two or more releases are required, and recapture censuses are also required two or more times (Itô and Yamamura, this volume). See ‘Hamada method’, ‘Itô method’, ‘Jackson positive method’, ‘Jackson negative method’, ‘Petersen method’, ‘Yamamura method’.
juvenile hormone (JH)	A sesquiterpene hormone produced by the corpora allata. Juvenile hormone is best known for its inhibition of development to the adult stage. It is also involved in the regulation of many physiological functions including diapause, heartbeat, migration, moulting and oogenesis (Gordh and Headrick 2001). One of the two major insect developmental hormones (the other is ecdysteroid or moulting hormone). During larval stages juvenile hormone maintains larval characters (Resh and Cardé 2003, Leak 1999). Juvenile hormone prevents moulting (Grimaldi and Engel 2005, Auburn 2008). See ‘insect growth regulator (IGR)’, ‘chitin synthesis inhibitor’.
kairomone	A chemical that is produced by one organism conveying information to another organism of a different species; it is advantageous to the recipient but detrimental to the producer of the chemical (Resh and Cardé 2003, Auburn 2008). An interspecific messenger substance that benefits the receiver but not the releaser, e.g. attractants, excitants (Pedigo 2002, Gordh and Headrick 2001, Coombs and Hall 1998, Coppel and Mertins 1977). A chemical or mixture of chemicals emitted by an organism, e.g. a plant, that induces a response in an individual of another species, e.g. an insect, that is beneficial to the receiving organism. Example: plant scent that makes the plant more easily identifiable to an insect pest (Maxwell and Jennings 1980, Bijlmakers 2008). See ‘allomone’, ‘pheromone’, ‘parapheromone’, ‘pheromone’, ‘synomone’, ‘semiochemical’.
karyotype	The visual appearance of the set of chromosomes of a typical somatic eukaryotic cell of a given species, individual, or cell strain. It is expressed in terms of chromosomal sizes, shapes, and number (Oxford 2006, Doncaster 2008, Burt and Trivers 2006, Lackie and Dow 1995, Ayala and Kiger 1984). The morphology of chromosomes is described in terms of their relative lengths, centromere positions, and secondary constrictions (King et al. 2006). A photomicrograph of an individual's chromosomes arranged in a standard format (Schlindwein 2006). See ‘chromosome’.
key pest	A perennial, severe and persistent pest of crop production; a pest that dominates the development and implementation of pest control activities. In the absence of human intervention, the pest commonly attains population densities that exceed economic injury levels (Gordh and Headrick 2001, Pedigo 2002, Maxwell and Jennings 1980). Pest species whose control is crucial for profitable crop production (Daly et al. 1998). See ‘secondary pest’, ‘intervention’, ‘economic injury level’.
kinetochore	Body which attaches laterally to the chromosomal centromere, and is the site of chromosomal tubule attachment (Schlindwein 2006, Watson 1976). Late in prophase, kinetochores develop on the two faces of the centromere that point toward the spindle poles, binding to centromeric DNA. The microtubules of the traction fibre attach to the kinetochores (King et al. 2006, Lewin 1985). See ‘prophase’, ‘centromere’.
kriging	An analytical technique. An interpolation procedure that relies on an autocorrelation function (the variogram) to provide weighting of nearby points used in the estimates. Kriging is ideally suited to the analysis of trap data, with interpolated output taking the form of contour maps or density surfaces of insect densities (Cox and Vreysen, this volume). A method of spatial interpolation based upon geostatistics. ‘Spatial interpolation’ is estimating the value of a variable at an unsampled location based upon measured values of the same value at known locations. The most common application of kriging is mapping (Glossary 2008). A complex function that looks at the existing spatial distribution of an element in several locations to derive a prediction of the spatial distribution of that same element in new or unobserved spaces (NAL 2008). See ‘geographic information systems (GIS)’, ‘geostatistics’.
land use	The way in which land is used, and for what purpose it is used, e.g. crop production, livestock production, nature reserve, human settlement, watershed, forest, etc. (Collin 2001). The deployment of land for any use. Competition for limited areas of land requires the establishment of priorities among claims, which is the object of land-use planning (Allaby 1994).
larvicide	Any substance that is used to kill or control the larvae of insects (Coombs and Hall 1998). A poison effective against larval insects (Hill 1997). Chemical agent that kills the larval stage of a pest or parasite (NAL 2008, Bijlmakers 2008). See ‘adulticide’, ‘trypanocide’, ‘parasiticide’.
larviparous	Reproduction in which the egg hatches within the female and the larva is deposited (Wall and Shearer 1997, Gordh and Headrick 2001). Giving birth to larvae instead of eggs (Hill 1997, King et al. 2006, Grimaldi and Engel 2005). Tsetse flies Glossina spp. are unique among pest insects in being larviparous, i.e. females do not lay eggs but gestate a larva in a uterus (one larva at a time) (Klassen and Curtis, this volume). See ‘adenotrophic viviparity’, ‘gestation’, ‘larviposition’, ‘viviparous’.
larviposition	The deposition of living larvae that have already hatched inside the female (Resh and Cardé 2003). See ‘adenotrophic viviparity’, ‘gestation’, ‘larviparous’, ‘viviparous’.
late embryonic lethality (LEL)	Death of an embryo, caused by genetic factors, at a late stage in its development.
lattice pattern	Consists of lines crossing each other with square or diamond-shaped spaces left between (Oxford 2008).
Law of Bergonie and Tribondeau	The following generalizations, with some exceptions, have become known as the Law of Bergonie and Tribondeau: The most radiosensitive cells are those (1) with a high mitotic rate, (2) with a long mitotic future (i.e. under normal circumstances, they will undergo many divisions), and (3) which are of a primitive type (Bakri et al., this volume).
leading edge	When a pest infestation is spreading in a certain direction, the front portion of the infestation, or leading edge, can through pest monitoring be observed over time to move in that direction.
Least Developed Countries (LDC)	Least Developed Countries are countries which, according to the United Nations, exhibit the lowest indicators of socioeconomic development, with the lowest Human Development Index ratings of all countries in the world. A country is classified as a Least Developed Country if it meets three criteria based on: low income, human resource weakness, and economic vulnerability. The classification currently applies to 49 countries (Wikipedia 2008). A list of Least Developed Countries is available from the United Nations (UN 2008).
lek	A communal display site where males aggregate for the sole purpose of attracting and courting females and to which females come for mating (FAO/IAEA/USDA 2003). Specific site where males gather to display and compete for the attention of females (Jolivet 1998, Daly et al. 1998, Gordh and Headrick 2001). A group of males defending territories for mating purposes; also a type of mating system or strategy (Aluja and Norrbom 2001). Refer to Horng and Plant (1993). See ‘mating arena’, ‘courtship’, ‘mating behaviour’.
lesion	A zone of tissue with impaired function resulting from damage by disease or wounding (Oxford 2006). A break in a chromosome is a lesion.
lethal gene	Any gene carrying a lethal mutation. Such mutations may only be fatal in the homozygous state (Oxford 2006). Mutated gene that is capable of causing death (Schlindwein 2006, Hoy 2003). A lethal mutation in a gene results in the premature death of the organism carrying it. Dominant lethals kill heterozygotes, whereas recessive lethals kill only homozygotes (King et al. 2006, Oxford 2006, NAL 2008, Lackie and Dow 1995, Ayala and Kiger 1984). See ‘gene’, ‘dominant lethal induction’, ‘dominant lethal mutation (DLM)’, ‘release of insects carrying a dominant lethal (RIDL)’, ‘lethality’.
lethality	The quality of being deadly (Webster 2008). See ‘lethal gene’, ‘dominant lethal induction’, ‘dominant lethal mutation (DLM)’, ‘release of insects carrying a dominant lethal (RIDL)’.
levy	The imposition of a tax, fee, fine, or subscription (Oxford 2008).
life cycle	The sequence of stages in the growth and development of an organism, eventually resulting in the reappearance of the first stage (Whiteside et al. 1988, Hill 1997). The sequence of events in the development of an insect that occur from birth (egg hatch) to reproduction (mating and egg laying) (Bijlmakers 2008, Weeden et al. 2000, Pedigo 2002). Progressive series of changes undergone by an insect from an egg to an adult (Collett 2001, Resh and Cardé 2003). The period of time between fertilization of an insect egg and the death of the individual which proceeds from that egg (Torre-Bueno 1978, Gordh and Headrick 2001).
life history	The taxonomic, biological and ecological studies of a species. Habits and changes undergone by an organism from the egg stage to its death as an adult (Pfadt 1962, Earthlife 2008). Made up of a series of instars and a series of moults or ecdyses between each instar and the next (Leftwich 1976). See ‘phenology’.
lifespan	The length of time that an animal lives (Scott 1996, Oxford 2008). See ‘longevity’.
Lincoln Index	A simple mathematical model to assess absolute insect population density (Southwood 1978). Recapture method, capture-recapture method. A number of live individuals is trapped, marked, then released. After a certain period, trapping is repeated, and the ratio of marked to unmarked individuals in the trapped sample is determined. It is assumed that the marked animals after release become randomly distributed in the population, and that all animals, marked or unmarked, have an equal probability of being trapped (Scott 1996). Refer to Vreysen (this volume), Itô and Yamamura (this volume). See ‘absolute density’, ‘apparent density’, ‘marking’.
linear energy transfer (LET)	The energy imparted to a medium by a charged particle of a specified energy, per unit distance. High-LET radiation (e.g. alpha particles, neutrons); low-LET radiation (X-rays, gamma rays) (Bakri et al., this volume; IAEA 1992; FAO/IAEA 2009; Koelzer 2008). The linear rate of loss of energy (locally absorbed) by an ionizing particle traversing a material medium (Borders 1991).
live-bait technology	In this technique, residual insecticides are applied to host animals that attract pest insects, e.g. tsetse flies, which are killed on contact with the insecticide (Mangan, this volume; Cox and Vreysen, section 3.2., this volume). The use of live animals to attract insect pests (Vale and Torr 2004). See ‘attract and kill’, ‘lure and kill’, ‘stationary-bait technology’.
locking	Failure of mating pairs to disengage upon completion of copulation (Bloem et al., this volume). See ‘copulation’.
locus	A locus is the specific position, in all homologous chromosomes, of a particular gene or one of its alleles (Oxford 2006, King et al. 2006, Schlindwein 2006, Hoy 2003, Doncaster 2008, Burt and Trivers 2006). The site in a linkage map or on a chromosome where the gene for a particular trait is located (Lackie and Dow 1995, Kahl 1995, Lewin 1985, Ayala and Kiger 1984). May refer to the gene itself (Resh and Cardé 2003). See ‘gene’, ‘allele’, ‘chromosome’.
logistic model	A classical continuous-time model to describe a sigmoidal increase in population density over time (Itô and Yamamura, this volume; Hill 1997). Logistic growth = Population growth that is influenced by the carrying capacity of the environment (Resh and Cardé 2003). See ‘population model’, ‘Hale-Malthusian’.
longevity	The length of life of an individual or a population (Hill 1997). See ‘lifespan’.
Lotka-Volterra model	A mathematical (differential equation) predator-prey model. Refer to Barclay (Box 2) (this volume). See ‘model’, ‘predation’, ‘prey’.
low pest prevalence area	An area, whether all of a country, part of a country, or all or parts of several countries, as identified by the competent authorities, in which a specific pest occurs at low levels and which is subject to effective surveillance, control or eradication measures (FAO 2006, IAEA 2003). Areas that are established by means of a systems approach through the application of a series of pre-and post-harvest suppression and mitigating measures (Klassen, this volume). Refer to Hendrichs et al. (this volume), Enkerlin (this volume).
Low-Income Food-Deficit Countries (LIFDC)	There are 82 countries on this list (as of November 2006). Criteria for a country to be on this list include: per capita income below the ‘historical’ ceiling, and net food trade position averaged over the preceding 3 years (FAO 2008).
lure	A chemical, food or colour that attracts insects; for the purpose of monitoring or control (Coombs and Hall 1998). Refer to IAEA (2003). In general, ‘lure’ is defined as a thing that attracts or lures an animal to do something (Oxford 2008), or anything that serves as an enticement (Webster 2008). See ‘attraction’, ‘bait’.
lure and kill	A technique to control insects by attracting them to a lure or bait (usually in a trap) which is associated with something, e.g. insecticide, that kills the attracted insects. See ‘attract and kill’, ‘lure’, ‘live-bait technology’, ‘stationary-bait technology’.
malaria	An acute or chronic (sometimes fatal) pan-tropical disease of humans caused by sporozoan parasites (Plasmodium spp.) and transmitted by various insects, e.g. anopheline mosquitoes (Gordh and Headrick 2001). See ‘vector’, ‘transmission’, ‘parasitism’, ‘pathogen’.
male annihilation technique (MAT)	The male annihilation technique involves the use of a high density of bait stations consisting of a male lure combined with an insecticide. An insect pest control method that reduces pest populations by employing mass trapping to lure and kill male insects before they have a chance to mate. Often used to control fruit flies (USDA 1993). Refer to Horng and Plant (1993), SPC (2002). See ‘attraction’, ‘bait’, ‘lure’, ‘attract and kill’, ‘lure and kill’, ‘stationary-bait technology’.
male recombination	See ‘genetic recombination’.
male relative performance index (MRPI)	Relative measure of the mating propensity of males, and indicates the degree of sexual compatibility (or isolation) between two strains/populations of insects. The mathematical formula for this quality control test is given in Calkins and Parker (Box 1) (this volume) and FAO/IAEA/USDA (2003). See ‘isolation index (ISI)’, ‘relative isolation index (RII)’, ‘female relative performance index (FRPI)’, ‘assortative mating’.
Maleness factor	Dominant genetic factor, usually found on the Y chromosome, which switches the sex determination cascade to the male mode. This type of sex determination system is found in many non-drosophilid Diptera like the Mediterranean fruit fly (and other fruit flies), the house fly, the sheep blow fly, and Megaselia scalaris (G. Franz, personal communication). Refer to Franz (this volume). See ‘sex chromosome’, ‘sex determining’.
male-only release	In the sterile insect technique (SIT), the release of sterile males only and no sterile females. This is achieved by sorting the sexes before release, or by releasing males produced in a genetic sexing strain. Male-only releases may introduce more sterility into a wild population than bisexual releases. Refer to Calkins and Parker (this volume), Franz (this volume). See ‘sex ratio’, ‘optimal sex ratio’, ‘overflooding ratio’, ‘sterile:wild ratio’, ‘sterile insect technique (SIT)’.
marker	A gene with a known location on a chromosome and a clear-cut phenotype, used as a point of reference when mapping a new mutant (King et al. 2006). Any gene of known function and known location on a chromosome (Oxford 2006). Gene that confers some readily detectable phenotype on cells carrying the gene, either in culture or in transgenic or chimeric organisms. Gene could be an enzymic reporter gene, a selectable marker conferring antibiotic resistance, or a cell membrane protein with a characteristic epitope (Lackie and Dow 1995). An identifiable physical location on a chromosome (e.g. restriction enzyme cutting site, gene, minisatellite, microsatellite) whose inheritance can be monitored (Schlindwein 2006). Marker genes include genes conferring resistance to antibiotics, expression of green fluorescent protein, eye colour, etc. (Hoy 2003). DNA size marker = A DNA fragment of known size used to calibrate an electrophoretic gel (Hoy 2003, Lewin 1985). See ‘genetic marker’, ‘selectable marker’, ‘gel electrophoresis’, ‘green fluorescent protein (GFP)’, ‘microsatellite’, ‘phenotype’,
market access	The extent to which a good or a service can compete with locally made products in another market (NAL 2008). Market access for goods in the World Trade Organization means the conditions, tariff and non-tariff measures, agreed by members for the entry of specific goods into their markets (Wikipedia 2008).
marking	Marking reared or captured insects in such a way that the mark is identifiable when a marked insect is captured or collected in the field. Refer to Parker (section 10) (this volume), Robinson and Hendrichs (this volume), Itô and Yamamura (this volume). See ‘dye’, ‘fluorescent dye’, ‘elemental marker’, ‘mark-release-recapture’.
mark-release-recapture	A technique of estimating insect population size by marking and releasing captured individuals and counting their proportional abundance in later samples (Daly et al. 1998). Refer to Itô and Yamamura (this volume), Vreysen (this volume), FAO/IAEA/USDA (2003), Southwood (1978). See ‘Hamada method’, ‘Itô method’, ‘Jackson positive method’, ‘Jackson negative method’, ‘Jolly-Seber method’, ‘Petersen method’, ‘Yamamura method’, ‘marking’, ‘dye’, ‘fluorescent dye’, ‘elemental marker’, ‘Lincoln Index’, ‘release’, ‘recapture’.
mass-rearing	The key concept that identifies mass-rearing is that insects are handled in groups and not as individuals (Dyck 2010). Rearing of insects as in a factory, often on a large scale, using procedures that handle insects in groups and not as individuals (IDIDAS 2008). Insect production in large numbers, as in production for release programmes (Weeden et al. 2000, Coombs and Hall 1998). Mass-rearing is a systematic enterprise accomplished with machinery in integrated facilities for the purpose of producing a relatively large surplus of insects for distribution (Leppla et al. 1982). In mass-rearing the objective is to produce large numbers of ‘acceptable’ insects at the lowest possible cost (Singh 1977). The production of insects competent to achieve programme goals with an acceptable cost/benefit ratio and in numbers per generation exceeding ten thousand to one million times the mean productivity of the native population female (Chambers 1977). Refer to Parker (this volume), Dowell et al. (this volume). See ‘mass-rearing facility’, ‘rearing’.
mass-rearing facility	A facility, e.g. building and equipment, in which insects are mass-reared. Refer to Dowell et al. (this volume), Parker (this volume), Dyck (2010). See ‘mass-rearing’, ‘modular rearing facility’, ‘rearing facility’, ‘centralized facility’, ‘satellite facility’.
mass-trapping	The use of traps, baited with pheromones or other attractants, to control insect pests. Chemical pesticides or biopesticides can be used in conjunction with the pheromones to kill target insects (Coombs and Hall 1998). Refer to Mangan (this volume), IAEA (2003). See ‘trap’, ‘attractive device’, ‘pheromone’, ‘sex pheromone’.
mate	An individual who has formed a bond with a member of the opposite sex for breeding; an individual actually engaging in a sexual union (King et al. 2006). To form an alliance for future breeding; to engage in a sexual union which may result in the fertilization of eggs (King et al. 2006). Male and female coming together in sexual reproduction. To pair for breeding, to copulate (MH 1997). See ‘mating’, ‘sexual behaviour’, ‘copulate’, ‘sperm transfer’.
mate-choice	The situation where an animal (usually a female) chooses as a mate a specific individual from a small group within the species (King et al. 2006). One member of a mating pair expresses a choice of mating, or not mating, with the other member. For example, a female can accept or reject a male for mating (Doncaster 2008). See ‘mating system’, ‘lek’, ‘courtship’, ‘sexual behaviour’.
mate-finding	Searching by one sex in a population to find the other sex to mate with it.
maternal effect	Any specific effect of the maternal genotype or maternal environment (phenotype) on the immediate offspring (Rieger et al. 1991). The influence of the mother’s phenotype or genotype on the phenotype of its offspring (NAL 2008). Determination of characters of the progeny by the maternal parent; mediated by the genetic constitution of the mother (MH 1997). Phenotypic trait that can be traced to the maternal genome (Malacinski 1988). See ‘genotype’, ‘phenotype’.
mating	The act of pairing a male and female organism for reproductive purposes (Schlindwein 2006). The meeting of individuals for sexual reproduction (MH 1997). The union of the sexes for reproduction; copulation (Torre-Bueno 1978, Leftwich 1976). See ‘courtship’, ‘sexual behaviour’, ‘copulation’, ‘sperm transfer’, ‘mate’, ‘mating behaviour’.
mating arena	See ‘lek’.
mating barrier	Factor that causes two individuals not to mate with each other, resulting in reproductive incompatibility and isolation; the factor could be genetic, ecological, temporal or behavioural. Tests of mating compatibility can determine if a mating barrier exists. Refer to Whitten and Mahon (this volume), Krafsur (this volume), Calkins and Parker (this volume), FAO/IAEA/USDA (2003). See ‘gamodeme’, ‘mating compatibility’.
mating behaviour	All behaviours performed by males and females to acquire mates for the purpose of reproduction (Aluja and Norrbom 2001). Refer to Lance and McInnis (this volume). See ‘lek’, ‘courtship’, ‘sexual behaviour’, ‘mating’.
mating compatibility	Relative measure of how readily two populations of insects are reproductively compatible (Lance and McInnis, this volume). Level of mutual attraction and tolerance in mating, and of functionality in sperm transfer, between male and female adults (IDIDAS 2008). Sexual compatibility is the degree to which two sympatric groups of animals tend to mate randomly without regard to their group of origin rather than mating selectively with members of their own group (FAO/IAEA/USDA 2003). Mating compatibility means that females of a given strain are able and willing to accept, for mating, the males of another strain; this also includes synchrony and other factors that cause reproductive disconformancy (FAO/IAEA/USDA 2003). Refer to Calkins and Parker (this volume), Lance and McInnis (this volume), FAO/IAEA/USDA (2003). See ‘mating barrier’, ‘relative isolation index’, ‘isolation index’, ‘male relative performance index’, ‘female relative performance index’, ‘compatibility’.
mating competitiveness	Level of rivalry between an adult male insect and another male in relation to mating opportunities with a female (IDIDAS 2008). The mating competitiveness of sterile males is a function of their mating propensity and mating compatibility (Lance and McInnis, this volume). Refer to Calkins and Parker (this volume), FAO/IAEA/USDA (2003). See ‘competitiveness’, ‘Haisch Index’, ‘relative sterile index’, ‘mating propensity’, ‘mating compatibility’.
mating disruption	The controlled release of large amounts of pheromones to confuse the females or males of an insect pest population, thus limiting their potential to mate (Coombs and Hall 1998). Use of pheromones to interfere with mating for pest control (Daly et al. 1998). The application of a formulated pheromone to a crop in order to interfere with mate finding by a pest insect (Resh and Cardé 2003). See ‘sex pheromone’, ‘area-wide integrated pest management’.
mating duration	Length of time spent in copula (FAO/IAEA/USDA 2003). See ‘copulation’, ‘mating’, ‘mating behaviour’.
mating efficiency	In the context of the formula in Box 8 of Barclay (this volume), mating efficiency is the number of females that get mated, as limited by the number of males, some of which have been trapped and killed. If no males are trapped, then all the females get mated, and alpha will be 1.0 (H. Barclay, personal communication).
mating frequency	The number of pairs of individuals which mated in a given time period (Schlindwein 2006). The number of times an individual mated successfully in a given time period.
mating index	See ‘mating propensity’.
mating inhibitor	See ‘mating disruption’.
mating propensity	The tendency to locate a mate, copulate and inseminate (Lance and McInnis, this volume). A measure of the level of eagerness or willingness of an insect to mate (Calkins and Parker, this volume). Measured by the percentage of individuals that mate (FAO/IAEA/USDA 2003). [Propensity = An inclination or tendency; the tendency for an individual insect to carry out an act, or for an individual event to occur (FAO/IAEA/USDA 2003, Boller and Chambers 1977)] See ‘male relative performance index’, ‘female relative performance index’.
mating speed	Time males take to copulate with virgin females when they are introduced into a container, reflecting overall male mating success [includes both speed of courtship and speed of copulation (mating duration)] (Hoffmann 1999). See ‘copulation’, ‘mating duration’, ‘courtship’.
mating system	The process of assuring that males and females of a given species interact sexually for reproduction. In the case of pest tephritid fruit flies, it is a female-choice system (FAO/IAEA/USDA 2003). The pattern of matings between individuals of a population, including such factors as extent of inbreeding, pair-bonding, and number of simultaneous mates (Schlindwein 2006). The pattern of mating in sexually reproducing organisms; two types of mating systems are random mating and assortative mating (Ayala and Kiger 1984). There are simple and complex mating systems; some mating systems are female-choice, and others male-choice (Lance and McInnis, this volume). Modes of gene transmission from one generation to the next by sexual reproduction (NAL 2008). Refer to Lance and McInnis (this volume). See ‘mate-choice’, ‘sexual behaviour’, ‘mating’, ‘mating behaviour’, ‘remating’, ‘monogamy’, ‘polyandry’, ‘polygamy’, ‘multiple mating’.
mating table	A portable platform (mating table) containing a tethered or wing-clipped virgin female moth (or one prevented from leaving the table) that permits a field-released or wild male moth to find the female and mate with her (Judd et al. 2006, Dyck 2010).
maximum likelihood estimate	An estimation procedure involving maximization of the likelihood or the log-likelihood with respect to the parameters. Such estimators are particularly important because of their many desirable statistical properties such as consistency, and asymptotic relative efficiency (Everitt 2006). The estimator for an unknown parameter given by the method of maximum likelihood (Clapham 1996). A term descriptive of a general econometric estimation technique which involves the maximization of the likelihood function of the sample observations with respect to the values of the parameters of the equation(s) being estimated. It chooses these values of the parameters which are ‘most likely’ to have generated the sample observations (Pearce 1992).
mechanical control	The control of pests by mechanical methods (Schmutterer 1969). The control of pests by the use of physical barriers, e.g. tree banding, screens, row covers, etc. rather than chemical or biological methods (Coombs and Hall 1998, Weeden et al. 2000, Pfadt 1962). Physical control = Physical actions (e.g. fruit stripping, host destruction, hand-picking, heat, cold, light, electricity, sound waves, radiation) taken to control a pest (USDA 1993, Pfadt 1962, Coombs and Hall 1998). Refer to Mangan (this volume). See ‘integrated pest management (IPM)’.
meiosis	A specialized form of nuclear division in which there are two successive nuclear divisions (meiosis I and II) without any chromosome replication between them. Each division can be divided into four phases similar to those of mitosis. Meiosis reduces the starting number of 4n chromosomes in the parent cell to n in each of the four daughter cells. Each cell receives only one of each homologous chromosome pair, with the maternal and paternal chromosomes being distributed randomly between the cells; this is vital for the segregation of genes. During the prophase of meiosis I (classically divided into stages: leptotene, zygotene, pachytene, diplotene and diakinesis), homologous chromosomes pair to form bivalents, thus allowing crossing-over, the physical exchange of chromatid segments. This results in the recombination of genes. In animals, meiosis occurs during the formation of gametes (gametogenesis), which are thus haploid (Lackie and Dow 1995, King et al. 2006, Oxford 2006, Schlindwein 2006, Hoy 2003, Doncaster 2008). See ‘gamete’, ‘gametogenesis’, ‘pachytene’, ‘haploid’, ‘mitosis’, ‘chromosome’, ‘homologous chromosomes’, ‘bivalents’, ‘crossing-over’, ‘chromatids’, ‘genetic recombination’.
meiotic drive	Any alteration in meiosis or the subsequent production of gametes that results in preferential transmission of a particular genetic variant (King et al. 2006). Any meiotic mechanism that results in the unequal recovery of the two types of gametes produced by a heterozygote (Hoy 2003, Doncaster 2008). The unequal recovery of homologous chromosomes during meiosis (Pedigo 2002).
meridic diet	Artificial diet some of whose ingredients are defined chemically and some not defined (Cohen 2004). Artificial diet of known chemical structure which contains at least one substance or preparation which is of unknown structure or uncertain purity, e.g. protein, yeast (Dyck 2010). See ‘artificial diet’.
messenger RNA (mRNA)	An RNA molecule that functions during translation to specify the sequence of amino acids in a nascent polypeptide (King et al. 2006). See ‘translation’, ‘RNA’.
metabolic heat	See ‘metabolic rate’.
metabolic rate	The rate at which an organism converts chemical energy into heat. Increased metabolic rate is correlated with greater oxygen consumption and with greater production of carbon dioxide, water, and heat (Resh and Cardé 2003). The rate of conversion of the physiologically utilizable chemical energy of food material into heat and work, and its utilization for the synthesis of body material. Any decrease in the stored energy of an organism is equal to the sum of the energy lost as heat and work (Scott 1996).
metaphase	The second phase of mitosis. During metaphase, the chromosomes move about within the spindle and eventually arrange themselves in the equatorial region of the spindle. The two chromatids are now ready to be separated and to move under the action of the traction fibres to the poles of the spindle (King et al. 2006, Schlindwein 2006). See ‘mitosis’, ‘meiosis’, ‘prophase’, ‘anaphase’, ‘telophase’, ‘interphase’.
metapopulation