In insects, mating often occurs after natal dispersal, and hence relies on a coevolved combination of sexual communication and movement allowing mate encounter. Volatile sex pheromones are widespread, generally emitted by females and triggering in-flight orientation of conspecific males. In parasitoid wasps, unmated females can start laying unfertilized eggs via parthenogenesis so that host pat...

Functioning of plant-aphid-natural enemy interactions may be associated with the structure and composition of withinfield vegetation, neighborhood fields and field borders, and the regional plant community of cropped and noncropped areas. Farmand region-scale vegetation in the wheat-growing area of the North American Great Plains was hypothesized to effect the abundance of two hymenopteran para...

cotton aphid, aphis frangulae gossypii glover, is a major pest of cucumber in iran. one of the important parasitoids playing role in population control of this pest in the fields and greenhouses is lysiphlebus fabarum marshall. in this study, we investigated sensitivity of different instars of cotton aphids and pupal stage of l. fabarum to field recommended and half-recommended concentration of...

in order to evaluate the efficiency of biocontrol agents of corn stem borer ,ostrinia nubilalis, experiment was conducted in a randomized complete block by five treatments and four replication, including, indoxacarb (avant)®, trichogrammawasps, bacillus thuringiensis var: kurstaki, integration of trichogramma sp. and bt., and control as treatments number 1 to 5. in treatments with parasitoid re...

The walnut aphid, Chromaphis juglandicola is a pest known in California for more than 100 years. The introduction of the parasitic wasp Trioxys pallidus from Iran in 1969 led to a dramatic success in the biological control of walnut aphid populations in California, and has provided sustained control of this devastating pest for the past 35 years. However, we are currently facing new walnut aphi...

Communities of insect herbivores and their natural enemies are rich and ecologically crucial components of terrestrial biodiversity. Understanding the processes that promote their origin and maintenance is thus of considerable interest. One major proposed mechanism is ecological speciation through host-associated differentiation (HAD), the divergence of a polyphagous species first into ecologic...

In this paper, we analyze the polymorphisms of parasitoid wasp polydnavirus. The polydnavius genome is normally dormant within the genome of the wasp, but is converted into particles that are injected into the infected host along with the wasp eggs. These particles contain genes which inhibit the immune system of the infected host, and are necessary for the eggs to mature. Within a population, ...

Antagonistic relationships between parasitoids and their insect hosts involve multiple traits and are shaped by their ecological and evolutionary context. The parasitoid wasp Cotesia melitaearum and its host butterfly Melitaea cinxia occur in several locations around the Baltic sea, with differences in landscape structure, population sizes and the histories of the populations. We compared the v...

Females of the parasitoid wasp Trichogramma turkestanica produce the putative polydeoxypropionates (2E,4E,6S,8S,10S)-4,6,8,10-tetramethyltrideca-2,4-diene and (2E,4E,6S,8S,10S)-4,6,8,10-tetramethyltrideca-2,4-dien-1-ol or their enantiomers as sex specific volatiles. The structures were assigned on the basis of GC-MS investigations using synthetic reference compounds.

Many species adaptively alter offspring sex ratios, yet little is known about how they obtain relevant environmental information. New work on the parasitoid wasp Nasonia vitripennis reveals that the presence of eggs on hosts provides a reliable cue allowing females to determine the degree of local mate competition and adaptively adjust offspring sex ratios.