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Entomology: knowledge in insect morphology, taxonomy and systematics, physiology, molecular biology, etho-ecology, rearing, control of insect plant, post-harvest and material pests, or vectors of diseases What makes insects so successful? - small body size (advantageous relation between body surface, volume and weight) - protective cuticle - highly developed sensorial and motorial system - high reproduction capacity - flight (insects are the only arthropods with flight ability) characteristics of insects • segmentation and tagmosis • Exoskeleton • segmented extremities • mandibular mouthparts • 1 pair of antennae • tracheal respiration • 3 pairs of legs If the appendices are paired then they have been evolved from extremities. Unpaired appendices are excrescences or protuberances of the cuticle only. Flight ability enables insects - to search actively for food sources or oviposition sites even over long distances - to search for mating partners - to disperse actively over a shorter or longer distance - to escape if being attacked Wings - are only lateral folds of the alinotum (part of the tergits) and, thus, excrescences of the exoskeleton and no extremities. - are inserted to the meso- and metathorax (originally also a pair of wings was inserted at the prothorax, which means, that early insects had three pairs of wings). Cerci Inserted at the 11. segment; filamentous, often modified (i. e. “Kneifer” of earwigs); serving defense, holding prey, or to infold wings (as in earwigs) outer structures modified into ovipositors - appendicular (true) ovipositors (homologue to legs at the 8. and 9. abdominal segment), may be modified to a sting (i. e. Hymenoptera) - substitutional (false) ovipositors (= only extendable / protrudable abdominal segments) (i. e. Diptera, Lepidoptera, Coleoptera, etc.)

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Males • Aedeagus (complete apparatus) consisting of: - Penis (penes) in singular or plural (organs for sperm transfer and - lateral inserted parameres (fixing apparatus) In crop protection: • Oral uptake of insecticides • High enzymatic activity to metabolise food and insecticides in the midgut • The microvilli border and midgut epithelial cells are target of insecticides and biocontrol agents (-endotoxin alone and active Bacillus thuringiensis) • Defecation and excretion of insecticides and their metabolites • Food conversion into bodymass Why to know the morphology of insect‘s reproductive organs? • The number of ovarioles determines the size of an egg clutch or the number of eggs per egg set • Usually, oviposition occurs in time intervals • Daily / regular / maximum egg production to assess fecundity and fertility of insect pests or beneficials  reproductive potential, necessary to calculate life-tables • To assess lethal effects of insecticides during oogenesis or embryogenesis Apposition eyes => have a limited light sensitivity due to the small diameter of facet lenses, however, they provide a good resolution. Superposition eyes have a wide light sensitivity but lacking a good resolution. Generation of sound: - stridulation - wing beat - sound membranes - sharp inhalation or exhalation of air Reproduction = reproduction of individuals of a species Growth = increase in biomass and size; reversible process Development = transition of an individuum into the next higher stage along an increasing hierarchy from the lowest to the highest reachable stage; irreversible process! The female will chose a male according to a variety of different features:: - optical characteristics - behavioural patterns (courtship, flight) - higher attractivity due to defense substances - due to feeding the females („nuptial gifts“ ) 2

Spermatophylax = a gelatinous bolus which functions as a nutritive addition for the female. Types of reproduction - Ovipary - Ovovivipary - Pseudoplacental vivipary - Hemocoelous vivipary - Adenotrophic vivipary Why to know the embryogenesis (practical point of view)? - determination of killing time / stadium of insecticides with ovicidal action. - determination of early- and late effects after disturbance of hormonal control of development by insecticides / sterilization. - determination of the preferred stadium / age of the host egg by egg parasitoids. Dyar‘s law: The relation of linear parameters of body size (width or length of the head capsule, width or length of a mandible) between subsequent larval instars is constant (range: 1.3 – 1.7). => Size after moult / size before moult = constant Przibram‘s law: The biomass duplicates within a larval instar and the linear parameters increase by factor 1.3 Larval types: 1. Polypod larvae

2. Oligopod larvae

3. Apod larvae

Insect food can be categorized by origin: plant animal consistency: solid liquid status: live dead developmental stage of the feeding insect: pre-imaginal adult carnivorous insects are categorized as: - predators - parasites - parasitoids

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solitary parasitoids oviposition of one egg only into the host; if superparasitization occurs, the larvae hatching from the parasitoid eggs struggle and only one will survive Superparasitization several females of the same parasitoid species are ovipositing into the same host gregarious parasitoids after superparasitization several parasitoid larvae can survive and develop successfully multiparasitization oviposition by several different parasitoid species into a common host hyperparasitization a parasitoid (larva) serves as host for another parasitoid species

Zoomimesis: resemblance with neglected animals (from the point of view of the aggressor!). Phytomimesis: resemblance to plant parts or organs (as leaves, flowers/blossoms, twigs, bark). Allomimesis: resemblance to dead material (frass, stones, sand).

osmeterium pouch which is everted if the larvae are touched.

Two different strategies: r-strategy (in disturbed ecosystems, species with broad ecological tolerance and high reproductive capacity), and K-strategy (mature ecosystems, stable populations, resource allocation mechanisms

indigenous (autochthonous) species - dispersion, abundance, categorization (pest, beneficial, indifferent species) non-indigenous (allochthonous) species - alien species (unintentional or intentional introduction into a new ecosystem, establishment and expansion of area) - invasive species (subgroup of alien species according their ecological behavior - dispersion, abundance, categorization (pest, beneficial, indifferent species) Invasive species are organisms (usually transported by humans) which successfully establish themselves in (and then overcome, otherwise intact) pre-existing native ecosystems.

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unintentional introductions of allochthonous species: Western corn rootworm; Citrus aphid; Onion aphid; European pepper moth In klinokinesis, the frequency or rate of turning is proportional to stimulus intensity In othokinesis, the speed of movement is dependent upon stimulus intensity

Feeding on a plant - plant tissue is far from optimal food for herbivorous insects. - the chemical composition of plants vary - within the plant - with species - with time - the nutritional requirements of insects vary with species and time - abiotic environmental factors alter food quality - biotic plant stressors alter food quality, setting up community and multitrophic species interactions - herbivores cope with nutritionally inadequate food by ingesting large amounts of it

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