Identification et evaluation des effets de differents facteurs biotiques abiotiques sur l'emission la reception pheromones sexuelles chez les mites. Evaluation l'utilisation resultats obtenus dans le controle populations insectes

Prevailing abiotic conditions may positively or negatively impact insects at both the individual and population levels. For example while moderate rainfall wind velocity provide that favour development, as well movement within between habitats, high winds heavy rains can significantly decrease life expectancy. There is some evidence adjust their behaviours associated with flight, mating foraging in response to changes barometric pressure. We studied different of three taxonomically unrelated...

Facultative diapause is a strategy that allows insects to initiate an additional generation when conditions are favorable, or enter they not. The occurrence of generations within one year can have profound effect on the ecology and evolution species. Most previous studies cues induce facultative in concentrated photoperiod temperature. In contrast, we studied effects host-plant quality induction larval subsequent voltinism polyphagous insect herbivore, Choristoneura rosaceana (Lepidoptera:...

Juvenile hormone has been implicated in the mediation of several reproduction-related events adult insects, but had previously found to play no role regulation sex pheromone production and release behavior ("calling") moths. In females true armyworm moth, Pseudaletia unipuncta, juvenile is shown be essential initiation both calling production. Females without corpora allata, source hormone, do not call produce pheromone, injection into allatectomized restored these activities. The armyworm's...

ABSTRACT. Adults of many species Lepidoptera, principally the males, frequent mud puddles, edges streams, carrion and animal excreta where they imbibe moisture, an activity referred to as ‘puddling’ Sodium ions are only known stimulus present which cause males at least two lepidopteran drink for extended periods. In European skipper Thymelicus lineola (Ochsenheimer) (Lepidoptera: Hesperiidae), puddle, even though have concentrations abdominal sodium 2–3 times that females emergence. During...

Food availability is a major component of habitat quality. For bumblebee field colonies, it unknown to what extent reproductive success limited by food relative other factors such as parasites. To assess the importance availability, we carried out experiment in Quebec City area, Canada, 1999 and 2000, using 45 colonies Bombus impatiens B. ternarius . Colonies whose nectar pollen supplies were increased regularly throughout season reached larger sizes (in number workers) had higher than...

It is generally assumed that the cost of producing ejaculates relatively low for males, although decline observed in spermatophore size with repeated mating certain lepidopteran species would suggest this not always case. However, despite such differences spermatophores very little research has been done to determine if female reproductive success affected by previous history her mate. A study was undertaken, using European corn borer, Ostrinia nubilalis, extent which (i) male lifetime...

Differences in the distribution of parasitized and unparasitized hosts has been used to infer modification host behavior by insect parasitoids. Data are presented showing that not only do behave differently from ones, but varies function physiological state parasitoid. Aphids containing nondiapausing parasitoids leave aphid colony mummify on upper surface leaves, whereas those diapausing plant concealed sites. Modification results selection a suitable microhabitat reduces incidence...

The calling behaviour of virgin female armyworms, Pseudaletia unipuncta (Haw.), was studied at 25° ± 0.5° and 65 5% RH under a 16L: 8D photoperiod. age which females started following emergence varied from 2 to 10 days, with mean 3.9 days. Due these differences comparisons on successive days were made using the “calling” rather than emergence. pattern individual females, observed every min, changed calling. Over 7 onset time advanced 396 301 min after scotophase, total spent per day...

The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic behavioral differences appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction pheromone lures different regions, but this could have been due inter-strain and/or geographic differences. Therefore, we investigated whether rice-strain males differed their response synthetic blends regions North America, the Caribbean South America. All...

Cruciferous plants are known to produce over a hundred different mustard oil glycosides, which derived from methionine, phenylalanine, or tryptophan. In oil-producing crops like Brassica napus (canola), the presence of indole glucosinolates in seed protein meals has decreased meal palatability and limited their value as animal feed. We have transformed canola with gene that encodes tryptophan decarboxylase (TDC) an attempt redirect into tryptamine rather than glucosinolates. Transgenic...

Sex pheromone traps were used to monitor the seasonal periodicity of fall armyworm, Spodoptera frugiperda (J. E. Smith), moth over a 2-year period at eight locations from French Guiana northward Canada. Results indicated progression movement by armyworm southern most in United States into Although survives throughout year Caribbean Basin, analysis capture and meteorological data for region provided no direct evidence that this reservoir continuous populations contributed significantly influx...

Abstract. 1. One possible component of successful parasitism by insect parasitoids is the reduction predation and hyperparasitism through modification host behaviour. 2. Just prior to death, potato aphids, Macrosiphum euphorbiae (Thomas), containing diapausing larvae parasitoid Aphidius nigripes Ashmead have been shown leave plant mummify in concealed sites, while those parasitized non‐diapausing individuals generally aphid colony on upper leaf surfaces. 3. The present study examines within...

Abstract Many insect species are migratory, but migration is energetically costly, leading to a trade‐off between and subsequent reproduction. Of importance the allocation of resources reproduction relative use essential nonessential fatty acids. How different ecological conditions experienced by individuals affect differential nutrients has not been well explored, especially in insects. Our goal was evaluate how reproductive (summer) migratory (fall) rearing source patterns acids used...

Abstract In aphidiine parasitoids, resources for growth and adult body size increase with host instar used by ovipositing females, but the fitness consequences of on are poorly documented. We compared male female A. nigripes adults that varied in as a consequence developing different instars their Macrosiphum euphorbiae . When reproductive was measured without considering time, wasps from small large hosts performed similarly, contributing 125–175 foundresses plus 100–180 sons to next...

The effect of competition among similarly aged larvae the alfalfa blotch leaf miner, Agromyza frontella (Rondani), was investigated in laboratory studies over a range larval densities (1–10 per leaflet) commonly found on Quebec. In these A. were to be resource limited when developing small leaflets and (or) with other larvae. Larval mortality owing interference (cannibalism) during first two instars, exploitation (starvation) third final instar, increased density-dependent manner. Prepupal...

Chemical mimicry is an essential part of certain interspecific interactions, where the outcome for both species may depend on degree to which original signals are mimicked. In this review, we discuss a number specific cases relating pollination and obtaining nutrient resources that believe exemplify recent advances in our understanding chemical mimicry. Subsequently, suggest avenues future ecological research should allow us gain further insight into evolution