learning host or prey-related olfactory cues may lead to increase efficiency and foraging capacity of biocontrol agents such as trichogramma egg parasitoid wasps in nature. the egg parasitoids, trichogramma species (hym., chalcidoidea, trichogrammatidae), are most commonly and important biocontrol agents that have successfully been utilized against several lepidopteran pests, especially through...

Barriers to gene flow can result in populations evolving into separate species, and understanding how these barriers evolve is a key step the process of speciation. This study investigates major barrier flow, mortality during development, two parasitoid wasp Nasonia vitripennis Walker N. giraulti Darling. Previous work has demonstrated high haploid hybrid males species shown potential rescue fr...

Biological control using hymenopteran parasitoids presents an attractive alternative to insecticides for reducing infestations and damage from the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), in retail and warehouse environments. We examined the potential for using combinations of the egg parasitoid Trichogramma deion Riley (Hymenoptera: Trichogrammatidae), and the ...

Although there is widespread agreement that the cost of oviposition underlies selective oviposition in insects, there is no consensus regarding which factors mediate the cost of oviposition. Models have suggested that egg costs are often paramount in those insects that do not continue to mature eggs during the adult stage (pro-ovigenic insects). Here we address the hypothesis that egg costs are...

1. Objectives The main objective was to measure real lifetime contributions of individual female Gonatocerus ashmeadi to parasitism of glassy-winged sharpshooter (GWSS) egg masses in citrus orchards. However it is unknown whether G. ashmeadi is proor syn-ovigenic. Gonatocerus parasitoids are generally classified as strictly pro-ovigenic (Jervis and Copland, 1996). Jervis et al. (2001) calculate...

developmental periodsof thegrapevine aphid, aphis illinoisensis shimer (hemiptera: aphididae) on the grape, vitis vinifera l., and its two parasitoid species, lysiphlebus testaceipes (cresson) (exotic) (hymenoptera: braconidae: aphidiinae) and aphelinus albipodus hayat and fatima (indigenous) (hymenoptera: aphelinidae) were studied at two constant temperatures (20 and 25 ± 2 oc), 70 ± 5 % r.h. ...

Life-history theory has suggested that individual body size can strongly affect the allocation of resources to reproduction and away from other traits such as survival. In many insects, adults eclose with a proportion of their potential lifetime egg production that is already mature (the ovigeny index). We establish for the solitary parasitoid wasp Aphaereta genevensis that the ovigeny index de...

Polyembryony has evolved independently in four families of parasitoid wasps. We review three main hypotheses for the selective forces favouring this developmental mode in parasitoids: polyembryony (i) reduces the costs of egg limitation; (ii) reduces the genetic conflict among offspring; and (iii) allows offspring to adjust their numbers to the quality of the host. Using comparative data and ve...