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Select the first letter of the word from the list above to jump to appropriate section of the glossary. Bold within the text of an entry indicates a cross-reference to another headword. The following abbreviations are used for:

pl. plural of a term
sing. singular of a term
adj. adjective

- A -


Third, hind major division of an insect body, for reproduction, digestion and excretion (show figure)


Inanimate environmental factors such as climate, temperature, etc., that do not derive directly from the presence of other organisms; see biotic

abundance (=population density)

Number of individuals of a species in a particular area

Acari (=Acarina)

Mites, ticks; order of the class Arachnida


Any agent suitable for the control or eradication of mites and ticks


In applied entomology, any chemical added to a pesticide to increase its toxicity

active constituent

See active ingredient

active ingredient (a.i.)

Actual toxic agent present in pesticide formulations

acute poisoning

Poisoning which occurs when a large amount of a pesticide is incorporated in a single go; the effect of the poisoning is seen quickly; see chronic poisoning


See adjuvant


In applied entomology, any material added to increase pesticide retention; different commercial preparations of methyl cellulose are used for this purpose


Spray additive to improve either physical or chemical properties of a pesticide; see also adhesive, emulsifier, sticker, supplement, wetter


Suspension of solid or liquid particles in air with droplets smaller than 50 µm


Science and study of the factors causing disease


Mechanical device in the spray tank to ensure uniform distribution of toxicant and to prevent sedimentation


Possessing wings; in the context of termites, winged reproductives (show figure)


Volatile messengers for communication between individuals of different species; see kairomone, allomone, pheromone and synomone


Communication chemical that benefits the producer by the effect it invokes in the receiver; see allelochemicals

alternate host

The other species of plant that is necessary for the completion of the life cycle of some insects and plant-disease producing organisms

alternative host

Organism which acts as one of several hosts to a pest or pathogen

ametabolous development

Development of primitive, wingless insects without metamorphosis; there are no marked changes in body form between the immature and adult insects; during their development the insects undergo more than 10 moults and continue to moult after sexual maturity


Series of organic compounds similar in function but not identical in structure to the original compound


(adj. antagonistic) (1) Organism interfering or inhibiting growth or presence of another; (2) chemical such as a drug, hormone, etc. producing opposite physiological effects; (3) muscles producing opposite movements so that contraction of one must be accompanied by relaxation of the other; opposite synergist


(pl. antennae) Paired, segmented sensory appendages on an insect’s head; commonly called ‘feelers’ (show figure)


Situated at or towards the front (show figure)


Medicine that is given to cancel out the effect of a poison

antifeedant (=deterrent)

Chemical of bitter taste or unpleasant scent disliked by some insects


In plant resistance, unsuitability of a plant to a feeding insect


Plant lice (Hemiptera: Aphididae)


Area at or adjacent to the tip of the wing or other structure (show figure)

apod larva

A larva without legs

aposematic coloration

Warning coloration; usually refers to the bright, often contrasting colours of distasteful or toxic species, but applies equally to alerting odours, audible signals or other similar features


Communication system based on warning signals

applied entomology (=economic entomology)

Study of both beneficial and injurious insects and related organisms like ticks, mites and spiders




Watery; made from or of water


Class of spider-like animals like true spiders, harvestmen, scorpions, mites, ticks, etc.


Class of the Arachnida, the true spiders


Referring to a tree, situated on a tree; eg. a termite nest attached to a branch of a tree (show figure)


Device for breaking up a liquid stream into fine droplets by a stream of air or centrifugal force


In applied entomology, any material with an odour that attracts certain insects; lure


Use of organisms for biological control by means of periodic liberation of organisms that are already present or that are less persistent but will be effective for some time after the release. Augmentation aims at an increase of the natural enemy’s population to an effective level of control and can be achieved by inoculation and inundative release


Lethal substance produced within an organism which kills it. In applied entomology, the use of a pest causing its own destruction


Disease control measures which rely on crops being grown in localities or seasons where or when a pest or disease is not active

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- B -


Any substance that destroys bacteria


Foodstuff used for attracting animals. In applied entomology, baits are usually mixed with a poison to form a poison bait


Of a kind disposition, not malign


Substance capable of killing a wide range of unrelated organisms

biological control (=biocontrol)

Human use of selective living organisms or viruses to control populations of pest species (plants or animals)


Progressive build-up of a pesticide residue in the bodies of organisms of a food chain


Animate features of the environment of organisms arising from the activities of other living organisms; as distinct from abiotic

biotic potential

Potential for reproduction in an optimum environment without limiting factors; see environmental resistance, reproductive potential

black sooty mould

Black stains on leaves caused by particular fungi growing on sweet excretions (honeydew) of aphids

blotch mine

Discoloured patch or blister on a leaf caused by a minute insect larva mining or burrowing between the upper and lower epidermis; see mine (show figure)

boom sprayer

Horizontal or vertical light frame carrying several spray nozzles


Organisms that tunnel or bore into wood and other materials like pin- and shot-hole borers, wood-boring weevils, longicorn beetles and Hymenoptera; termites, strictly speaking, are not borers


Clutch of individuals that hatch at the same time from the eggs produced by one set of parents

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- C -


See outbreak


Class of synthetic insecticides


In applied entomology, any material serving as diluent and vehicle for the active ingredient of a pesticide; usually in dusts


Structurally and functionally specialised, distinct groups in social insects, usually differing in behaviour, eg. reproductives, workers, soldiers (more info)


Worm-like, larval stage of moths and butterflies


Chemical used to render an insect sterile without killing it


A rigid nitrogenous polysaccharide or proteoglycan found in many arthropod exoskeletons and hyphal walls of fungi

chitin synthesis inhibitor

A class of insecticides that prevents chitin formation

chronic poisoning

Poisoning which occurs when small amounts of a pesticide are taken into the body over a long period of time.; the small doses eventually add up to enough poison to cause the symptoms of poisoning to appear; see acute poisoning

chronic toxicity (=cumulative toxicity)

Capability of a pesticide to be injurious after repeated exposures


Protective silken covering which encloses the pupa of several endopterygote insect groups, usually spun by their larvae; also used for any kind of enclosure of immature stages eg. eggs, larvae or pupae (show figure)


Beetles and weevils




Group of individuals, other than a single mated pair, which constructs nests and rears offspring in a cooperative manner; see social insects (more info)


In applied entomology, term referring to chemical materials that can be mixed together without changing their effects adversely on pests or plants

complete metamorphosis

Metamorphosis in holometabolous insects which in general has four stages - egg, larva, pupa, adult - each entirely different from the others; see gradual and incomplete metamorphosis

concentrate spraying

Direct application of an active ingredient without dilution

contact poison

Chemical that kills when it contacts some external parts of a pest


In applied entomology, prevention or reduction of losses from pests by any method; see eradication

conventional insecticides

Chemical insecticides


Basal segment of the insect leg

crop rotation

Successive growing of different crops on the same area of land

cumulative toxicity

Capability of a pesticide to be injurious after repeated exposures; see chronic toxicity


In applied entomology, the application of a pesticide during severe infestation of crop


The non-cellular skin or integument of insects consisting of chitin, structural proteins and pigments; in larvae it is shed at intervals to allow growth


Referring to or made from the cuticle

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- D -


Reproductive termite that has lost wings (show figure)


Made from or related to skin

dermal toxicity

Poisoning through the skin

deterrent (=antifeedant)

Chemical of bitter taste or unpleasant scent disliked by some insects


Identification of a specimen or the cause of a disease


Progressive death of twigs or leaves beginning at the tips


Any liquid or powdered material that is used to reduce the concentration of a chemical for spraying or dusting purposes


True flies, mosquitoes, gnats, midges, sandflies, punkies, etc.


Substance that removes contaminant organisms from surfaces


In applied entomology, to kill or inactivate pests present on the surface of plants or plant parts or in the immediate vicinity, eg. in soil


Movement of an individual or population away from its birth site


Substance that facilitates the production of suspensions or emulsions in chemical sprays


Active during the day


To, near or belonging to the back (show figure)

dose (=dosage)

In applied entomology, the quantity of a pesticide applied per individual, or per unit area or per unit volume or per unit weight


In applied entomology, spray or dust carried by natural air currents beyond the target area


In applied entomology, equipment suitable for the application of pesticide dusts to a target

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- E -


Shedding of the larval or pupal cuticle

economic damage

Injury done to a crop that will justify the cost of artificial control measures

economic entomology

See applied entomology

Economic Injury Level (EIL)

Pest density at which the damage caused by a pest equals the costs of its control (show figure)

Economic Threshold Level (ETL)

Pest density at which control must be applied to prevent the Economic Injury Level being reached (show figure)


Zone of transition between clearly demarcated groups of organisms or communities of two different habitats; see edge effect (show figure)

emulsifiable liquid

Liquid that will form an emulsion when it is mixed with water


Spray additive which permits formation of a stable suspension of oil droplets in aqueous solutions or aqueous solution in oil


Dispersion of one liquid in another in the form of tiny droplets


(adj. endemic) Confined to certain localities. For instance a species native to a particular place and found only there or a disease occurring in certain individuals or areas


Study of insects and their allies


(adj. entomopathogenic) Pathogen that particularly attacks insects

environmental resistance

Total of limiting environmental factors, working against the biotic potential of reproduction in an optimum environment, thus restricting populations from growing indefinitely and getting out of control

epicormic shoot

Shoot growing from the trunk of a plant


(adj. epidemic) Referring to the spread of a disease from its endemic area or from its normal host


Substance which eradicates a pathogen from the tissues of a host


Complete removal or elimination; see control


(pl. erinea) Abnormal development of epidermal plant cells or a deformation of the plant hairs caused by gall, rust and blister mites; erinea appear as brightly coloured patches on the foliage and might be mistaken for fungal growth


Social behaviour exhibiting cooperation in reproduction and division of labour, with overlapping generations


Control of pests or diseases achieved by excluding them from an area or country, often as a result of phytosanitation or quarantine legislation


(used only in the plural) Cast off cuticle of the larva or pupa after a moult

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- F -

faecal mottling

Spotting in timber caused by termites applying faecal pellets to their gallery walls

faeces (=feces)

(adj. faecal) Solid excretions of the alimentary channel


(pl. femora) Third segment of the insect leg, between the trochanter and the tibia


Ability to reproduce; reproductive rate of a female


In applied entomology, the inert component of pesticide dust or granule formulation

fluorescent tracer

Fluorescent material added to a pesticide to aid the assessment of spray deposits on plants


Components and proportions of additional substances that accompany an insecticide when prepared for application


Solid faecal material and discarded waste produced by insects, eg. sawdust of wood boring beetles


Any material that when in the form of gas or vapour destroys organisms


Application of gases or vapour to infiltrate soil, or stored products to kill pests


Any agent that kills or inhibits fungi

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- G -


Aberrant growth (tumor) of plant tissues eg. leaves, stem, petiole, etc., caused by the activity of another organism, often by oviposition or piercing-sucking action of some mites, Homoptera and gall wasps (Hymenoptera) (show figure)


Enclosed tunnels and chambers made by insects

generation time

Interval between the production of eggs in one generation and the production of eggs in the next generation

gradual metamorphosis

Simple metamorphosis of exopterygote insects in which the nymphs are terrestrial and resemble the adults in general form and mode of life except for the absence of functional wings and reproductive organs; see complete and incomplete metamorphosis


Coarse particle of inert material such as pumice or rice husks, that is impregnated or mixed with a pesticide mainly for soil application

granule applicator

Device able to apply measured quantities of granules

grease band

Adhesive material such as resin, applied as a band around a tree to trap or repel ascending wingless insects


Larva of a beetle

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- H -


(adj. hazardous) In applied entomology, the chance that harm will come to beneficial forms of life from the use of a pesticide


(adj. hemimetabolous) Insect orders with incomplete or gradual metamorphosis


Hemipteran suborders Heteroptera, Stenorrhyncha and Auchenorrhyncha, comprising true bugs, cicadas, aphids, scale insects, mealy bugs, tree, plant and leaf hoppers, jassids, spittlebugs, lerps, psyllids, etc.


Any agent or chemical used in the destruction or control of weeds

herbivore (=phytophage)

(adj. herbivorous) Eater on plants


Suborder of the order Hemiptera, comprising the true bugs


(adj. holometabolous) Insect orders having complete metamorphosis with pupal stage


Series of organic compounds with similar properties but differing from each other by some radical


The two Hemipteran suborders Stenorrhyncha (aphids, plant lice, scale insects, psyllids, mealy bugs, etc.) and Auchenorrhyncha (cicadas, spittle bugs, tree, leaf and plant hoppers)


Sweet secretions of water and carbohydrates released by aphids and other Homoptera as liquid faeces; honeydew dripping onto leaves is often stained black by mould, called black sooty mould


Molecules that are secreted directly into the haemolymph (or blood of higher animals) by ductless glands and carried to specific target cells or organs by whose response they bring about a specific and adaptive physiological response. Hormones are sometimes incorrectly referred to as chemical messengers


Organism that harbours another, especially a parasite or parasitoid, either internally or externally

host preference

Host specifity, host selectivity, to prefer one host over another


Sawflies, wasps, ants, bees, bumblebees

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- I -


(pl. imagines, imagos) Adult insect


(adj. immune) Ability of animals or plants to resist infection by parasites and effects of other harmful agents; essential requirement for survival, since most organisms are continuously menaced by viruses, bacteria, fungi or parasitic animals


Not compatible; not able to live together; in applied entomology, incapable of forming a stable mixture with another chemical

incomplete metamorphosis

Development in which the immature aquatic stages (naiads) differ significantly from the adults, and which lacks a pupal stage; see complete and gradual metamorphosis

inhalation poison

Insecticide with fumigant action


Without active biological or chemical properties


To enter and establish a pathogenic relationship with a host; to enter and persist in a carrier organism


(adj. infected) Process of, or state arising from, being infected with a protozoan, fungal or bacterial pathogen or parasite


To occupy and cause injury to either plants, animals, soils or products valuable to man


(adj. infested) Process of, or state arising from, being infested with a metazoan pathogen or parasite


Device for positioning a pesticide into soil or below the surface or into the transport system of a plant


In biocontrol, the periodic release of a natural enemy, which breeds so that the progeny provide control


Part or quantity of a pathogenic organism which can infect a host

Insecta, insects

Class of Arthropoda whose members have a body with distinct head, thorax and abdomen; the head bears one pair of antennae and paired mouthparts; the thorax bears three pairs of legs and one or two pairs of wings in winged insects (Pterygota) and none in primarily wingless insects (Apterygota); the abdomen bears no legs but other appendages might be present; insects are the most diverse class of organisms


Any agent effective against insects


Period between the hatching of the egg and the first larval moults (ecdysis), and the period between two successive ecdyses; synonym for stadium

integrated pest management (IPM)

Integration of chemical means of pest control with other methods, notably biological control and habitat manipulation


Mixed planting of crops; see polyculture

inundative release

In biocontrol, swamping a pest with large numbers of control agents, with control deriving from the released organisms rather than any of their progeny



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- J -


Liquid emitted from a nozzle


Immature, not yet fully developed

Juvenile Hormone (JH)

Insect hormone involved in moulting process, suppressing the final moult

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- K -


Communication chemical that benefits the receiver and is disadvantageous to the producer; see allelochemicals


Male primary reproductive in termites and ants (show figure)

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- L -


(pl. larvae) The feeding, wingless, sexually immature, developmental stage of an insect after emerging from the egg, eg. caterpillar, maggot, grub; often restricted to holometabolous insects, but sometimes used for any immature insect that differs strongly from the adult; in mites, the first immature instar followed by the protonymph; see nymph, naiad


Any agent effective against insect larvae


Present, but inactive, not apparent

LC50 value

Lethal concentration of a poison in air or liquid, causing the death of 50 % of a large group of test animals of the same species by inhalation or otherwise; measured in mg active ingredient (a.i.) per kg body weight

LD50 value

Lethal dose of a poison, orally or dermally, causing the death of 50 % of a large group of test animals of the same species; measured in mg active ingredient (a.i.) per kg body weight

leaf miner

Feeder on the mesophyll layer between the upper and lower epidermis of a leaf


Moths and butterflies


In nymphal Psyllidae (Hemiptera) a delicate and complex shelter produced from a carbohydrate secretion from the anus (show figure); see scale


Disruption and necrosis of host tissue caused by a pathogen, or the toxic saliva of certain Heteroptera




In applied entomology, the release of organisms for biological control

life cycle (=life history)

Time it takes for an insect to develop from egg to adult; during its life cycle an insect undergoes a progressive series of changes; sometimes considered as lineal succession of organisms from fertilisation to death


‘Earth measuring worm’; caterpillar of the moth family Geometridae with only one pair of abdominal prolegs and which moves by looping its body

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- M -


Legless larval insect, usually with a reduced head, frequently the larva of a fly

male confusion

See mating disruption


Malicious, evil, spiteful, not benign


(adj. mandibulate) Sclerotized, sometimes dentate (toothed) jaw of mandibulate insects


Possessing mandibles

mating disruption

Form of insect control in which synthetic sex pheromones, usually of the female are maintained artificially at a higher level than the background, interfering with mate location; sometimes also referred to as male confusion


Relatively abrupt change in body form between the end of immature development and the onset of the adult phase; see incomplete, gradual and complete metamorphosis


Gallery or burrow, visible beneath the epidermis of plant tissue made by a larva. A leaf mine for instance is a gallery in the mesophyll layer between the upper and lower epidermis of a leaf (show figure)


Having the property to mix well

miscible liquid (m.l.)

Formulation of pesticide in which the technical product is dissolved in an organic solvent, which on dilution, is dissolved in the water carrier

mist blower

Spraying device that produces a fine air-carried spray


See acaricide


See mould


See moult


Observation for a particular purpose as to keep track of crop development and insect infestation


Extensive cultivation of only one crop species resulting in very low species diversity and high susceptibility of the crop to pest attack (more info); see polyculture


(adj. monophagous) Eater of only one kind of food, used particularly by specialised phytophages


Death rate


Microfungus, often visible as black or dark stains on surfaces


In insects, the formation of a new cuticle followed by shedding of the old cuticle (ecdysis)

multiple resistance

Concurrent existence of two or more ‘defence’ mechanisms against an insecticide in a single pest population

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- N -


Immature stage of aquatic hemimetaolous insects; see nymph, larva


With a pronounced snout; in termites, soldiers possessing a snout (show figure)


Death of cells or tissues, especially through disease


Reproductive termite assisting the queen in laying eggs (show figure)


Active during the night

non-target organism

See target organism


Harmful; opposite of innocuous

nuptial flight

Mating flight of winged queens and males of Hymenoptera and termites


Larval instar of hemimetabolous insects; see larva, naiad

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- O -


Compulsory, exclusive


Blocking, shutting or closing; eg. the closing of the bark around an injury


(no plural) Descendant from an ancestor; sons, daughters, grandchildren, etc.


Referring to the mouth


Class of insecticides containing chlorine


Class of insecticides containing phosphorous


Locusts, grasshoppers, crickets, katydids, etc.

outbreak (=calamity, plague)

Temporary condition that is characterised by excessive insect numbers and - if it is a pest species - injury to valuable materials or products; sporadic calamities occur suddenly in a small, restricted area and vanish after a short period of time; periodic outbreaks happen at more or less regular intervals


Any factor or chemical that destroys eggs


Act of laying or depositing eggs


Modified hollow or sheath-like, paired abdominal appendages of female insects for laying eggs

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- P -


(adj. parasitic) Organism that lives at the expense of another (host) which it does not necessarily kill; parasites that live externally on the host are called ectoparasites, those that live inside the host are termed endoparasites; see parasitoid


Symbiotic relationship between two species in which one species, the parasite benefits to the detriment of the other, the host but usually without causing its death


Internal or external parasite that ultimately causes the death of its host

parts per million (ppm)

Measurement of concentration, eg. the proportion of a toxicant present in relation to that of plant material on which it has been deposited; usually used in connection with the edible proportion of a crop and its suitability for consumption


Disease-causing parasite, often microorganisms



periodic release

Regular release of biocontrol agents that are effective in control but unable to establish permanently


Property of some pesticides that can remain unaltered in the environment for a considerable long period of time


Any organism that is judged by man to cause harm to himself, his crops, livestock or his property in general

pest resurgence

Rapid increase in numbers of a pest following cessation of control measures or resulting from development of resistance and/or elimination of natural enemies


Toxic or poisonous chemical used to control or kill pest organisms; a term of wide application which includes all the more specific applications, eg. insecticide, acaricide, fungicide, herbicide, etc.

pesticide resistance

Result of a selection of individuals that are genetically predisposed to survive a pesticide; see multiple resistance, pesticide tolerance

pesticide tolerance

Ability of an individual to survive an insecticide not necessarily due to genetic predisposition


Volatile substance secreted by an individual, that produces a certain response in other individuals of the same species; pheromones can act as sex attractants, or can be engaged in communication, courtship, identification of individuals of the same nest and warning of danger

physical poison

Chemicals that are applied to suffocate target insects by means of dust or to disrupt the cuticle by using petroleum oil, detergents or organic solvents

phytophage (=herbivore)

(phytophagous) Eater of plants or materials of plant origin


Measures requiring the removal or destruction of diseased or infested plant material likely to form a source of re-infection or re-infestation


Smaller hole in wood of a living or dead tree made by wood boring beetles; see shot-hole

plant resistance

Range of inherited mechanisms by which plants resist insect and, in general, pest attack; see antixenosis, tolerance

poison bait

See bait


Cultivation of several crops in the same area, resulting in higher species diversity and lower pest susceptibility (more info); see monoculture, intercropping


(adj. polyphagous) Eater of several species of plants or of a variety of different foods


Group of conspecific individuals (of the same species), commonly forming a breeding unit and sharing a particular habitat at a given time

population density (=abundance)

Number of individuals per area or volume

powderpost beetles

Beetles of the subfamily Lyctinae (Bostrichidae) and the closely related furniture beetles (Anobiidae) that bore seasoned and unseasoned timber causing structural damage (more info)


(adj. predacious, predatory) Preying on other organisms; see predator, prey


Animal that uses in its life two or more other individual animals (prey) as food


In termites, an intervening stage between soldier and worker


(adj. preventive) In applied entomology, the protectant application of a pesticide before a predicted infestation of a crop


Food item for a predator

primary reproductives

In termites, the queen and king, founders of a colony (show figure)


Tubular organ of insects used to suck in liquid food (show figure)


Offspring, descendants, young


In applied entomology, measures that are continuously applied for the prevention of outbreaks


In applied entomology, the preventive application of a pesticide before a predicted infestation of a crop


Variety of defined geographic origin


In ‘lower’ termites the equivalent of the worker caste, comprising immature nymphs or undifferentiated larvae that have the ability to change into other castes


(pl. pupae) Resting stage between the last larval instar and the adult in the life cycle of holometabolous insects; also termed chrysalis in Lepidoptera


Hardened skin of the final instar larva in which the pupa forms


Becoming a pupa


One of the insecticidal chemicals of pyrethrum Taneacetum cinerariaefolium (Compositae)


Class of insecticides with structural similarity to pyrethrin

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- Q -


Examination, observation, treatment and/or isolation of organisms or particular products for a certain period of time in order to prevent the spread of pests and diseases. Quarantine is one of the most important pest management tools for islands nations


Female belonging to the reproductive caste in eusocial or semisocial insects (show figure)

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- R -


Substance disliked by particular insects, driving them back

reproductive potential

Potential of reproduction limited by environmental factors; the result of reduced biotic potential depending on fertility, length of the life cycle and sex ratio; see environmental resistance

reproductives, reproductive caste

In social insects, individuals that are responsible for the production of offspring; see queen, king, neotenic, alate, de-alate (show figures)

residual poison

Poison remaining in the pest’s body for some time after the application and being still capable of harming the pest


In applied entomology, the amount of pesticide remaining in or on plant tissue or in soil after a given time, especially at harvest time


(adj. resistant) Ability of an organism to withstand, suppress or retard the injurious effects, eg. of pesticides or pathogens; see environmental resistance, pesticide resistance, plant resistance, multiple resistance


Disease symptom in which plant tissues are destroyed


Chemical derived eg. from Derris spp. (Leguminosae) with insecticidal and other toxic effects


Type of disease characterised by the production of pustules on the surface of the host caused eg. by fungi or mites

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- S -


Removal and/or destruction of diseased material in order to reduce inoculum; phytosanitation refers to plant material


(1). Flattened and modified hair of moths and butterflies (Lepidoptera); (2). in most scale insects (Hemiptera: Coccoidea) a covering made of waxy substances for the protection of eggs, nymphs and adults; the scale is called lerp in Psyllidae (Hemiptera) and test in Diaspididae (Hemiptera)

scale insect

Member of the superfamily Coccoidea (Hemiptera); see scale

secondary pest

Previously harmless insect or other organism becoming a pest following a primary pest attack or pesticide treatment against a primary pest

selective pesticide

Pesticide that destroys certain species of pests and leaves others relatively unharmed


Any chemical used in intra- and interspecific communication, classified as pheromones and allelochemicals


Social behaviour in which individuals of the same generation cooperate and nest-share with some divisions of reproductive labour

serpentine mine

Mine that is curved or coiled, becoming gradually larger to a head-like end (show figure)

sexual dimorphism

Distinct sets of phenotypic secondary sexual characteristics for females and males of a species; in other words: a male looks different from a female; males and females might differ in body size, coloration of body or wings, patterns of songs, presence and shape of wings and appendages like antlers, feelers, etc.


Larger hole in wood of a living or dead tree made by wood boring beetles; see also pin-hole

social insects

All termite and all ant species as well as some bee and wasp species that form colonies and have structurally and functionally specialised, distinct groups of individuals; see caste


In social insects, an individual belonging to the soldier caste involved in colony defence (show figure)


In applied entomology, carrier solution in which the pesticide is dissolved to form the concentrate


Group of individuals sharing the same features and forming a reproductive community, producing fertile offspring; abbreviated sp. (singular) and spp. (plural)


Device for the application of pesticide sprays

spreader (=wetter, surfactant)

In applied entomology, any material added to a spray to lower the surface tension and to improve spread over a given area


Period between moults, instar duration or intermoult period


Any substance suitable for sterilisation


Devoid of living organisms, infertile

sterile male technique

Means of controlling insects by swamping populations with large numbers of artificially sterilised males, competing with the lower number of fertile males


To make sterile by killing any microorganisms present; to render infertile


In applied entomology, material of high viscosity used to stick powdered seed dressings on to seeds

stomach poison

Insecticidal poison that acts after ingestion into the gut


One of the elongate parts of piercing-sucking mouthparts (see figure), a needle-like structure


Under the surface of the earth, underground (see figure)


See adjuvant, additive

supplementary reproductive

In termites, a potential replacement reproductive within a nest which does not become alate; also called neotenic


See spreader


(adj. susceptible) Capability of being infected or infested, easily becoming diseased, not resistant


In physics, a liquid containing very small particles of solid material that will not dissolve


Evidence of a disease, expressed by the reaction of the plant or animal to the presence of the irritating factor or organism; see syndrome


Group of concomitant symptoms, often characteristic of a particular disease or pest attack


Enhancement of the effects of two substances that is greater than the sum of their individual effects; in applied entomology, the increased toxic effect of a pest-control chemical


(adj. synergistic) Chemical which when added to a pesticide improves its performance; very often the synergist on its own is not a pesticide


Communication chemical that benefits both receiver and producer; see kairomone and allomone


Compounded in the laboratory, as opposed to occurring naturally

systemic insecticide

Referring to insecticides incorporated by the body of a host (plant or animal) that kills insects feeding on the host; eg. an insecticide is absorbed through leaves, then spread via the vascular system to all parts; insects acquire the poison by eating any part of the plant

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- T -

target organism

In applied entomology, the species of a pest organism intended to be controlled by means of chemical methods


Most distal part of the insect leg, usually containing five segments

technical product

In applied entomology, the usual form in which a pesticide is prepared and handled prior to formulation; usually at a high level of purity of 95 to 98% but not completely pure


(pl. termitaria) Termite nest (show figures)


See scale


Chemicals which have a curative action on diseases


Curative, capable of eradicating or reducing the effects of a disease


The middle of the three major divisions (tagma) of the adult insect body bearing the legs and the wings (show figure)


Minimum level of a stimulus required to initiate a response; see economic threshold level (ETL) and economic injury level (EIL) (show figure)


(pl. tibiae, adj. tibial) Fourth segment of the leg


Mass of cells which make up organs of organisms


Ability of a plant to withstand pest attack and recover from it; also used for the amount of toxic residue allowable on or in edible substances under the law


Ability to poison or to interfere adversely with the vital processes of organisms


Science dealing with the nature and effects of poisons and venoms


(adj. toxic) Poisonous or venomous substance produced by an organism

trap crop

Crop, sometimes of wild plants, grown especially to attract pests or diseases and, when infested or infected, either sprayed or collected and destroyed; trap plants are usually grown between the rows of the crop plants or around the edges of the field


Small second segment of the leg, between the coxa and the femur (fig. 2-19)

tumor (=tumour)

Swelling caused by uncontrolled growth of cells

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- U -

ultra-low-volume (ULV) spraying

Application method of sprays using very low volumes of a pesticide

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Literally a bearer; specifically a host of a disease transmissible to another species


Alive, even if in a dormant state


Virus particle


(adj. virulent) Ability to overcome the body defence of a host, to invade and injure the tissues of the host and to eventually produce diseases


Minute intercellular disease agent


Able to form a gas from a liquid or solid at room temperature

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- W -

waiting period

See withholding period


Any plant in the ‘wrong place’, particularly used of plants away from their natural range, or invading human monocultural crops


Any agent suitable for the control of weeds

wettable powder (w.p.)

Powder that is easily wetted by water and will go into suspension


See spreader

withholding period

Recommended period of time that has to be allowed between the application of an insecticide and the harvest of a crop, so that residues of the insecticide can be degraded and eliminated; the withholding period depends on the crop species, the insecticide used, the temperature and the intensity of sunlight and varies between several days and weeks


In social insects, a member of the sterile caste that assists the reproductives (show figure)

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- X -


(adj. xylophagous) Eater of wood

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- Z -


Plant galls induced by animals such as insects, mites and nematodes, as opposed to those formed by the plant response to microorganisms

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Michael F. Schneider, 1999