We investigated the effect of mutual interference on the attack efficiency and the rate of successful parasitism on the parasitoid Spalangia cameroni (Perkins) attacking pupae of the stable fly Stomoxys calcitrans (L.). Female parasitoids (2, 4, 8, 16, or 32) were exposed to 100 fly pupae during 24 h. The number of pupae that were attacked and the number successfully parasitized increased with ...

Models of parasitoid-host dynamics are analyzed that include direct density dependence in the host population and either parasitoid- or host-density-dependent variation in parasitoid recruitment per parasitized host (parasitoid "yield"). The principal question addressed is how these forms of density dependence in parasitoid dynamics combine with aggregated parasitism to affect the stability of ...

rearing methods for bracon hebetor (say) (hym., braconidae) were investigated in the series of laboratory experiments designed to enhance the yield of the mass rearing of this parasitoid for biological control of lepidopteran field and stored product pests. in these experiments, the effects of parasitoid and host densities on fertility and sex ratio of b. hebetor were assessed. in parasitoid de...

Autoparasitoids, an important class of intraguild predators used in classical biological control, have a unique biology. Females develop as primary endoparasitoids of scale insects and whiteflies. Males develop at the expense of conspecific or heterospecific parasitoid prepupae. To evaluate the effect of autoparasitism on host suppression, system stability, and parasitoid coexistence, stage-str...

Anaphes iole Girault is a solitary egg parasitoid which attacks Lygus spp. In a low-parasitoid-density experiment (parasitoid:host ratio 5 1:40) 10.0% of available Lygus hesperus Knight eggs were superparasitized by A. iole. However, in experiments with a high parasitoid density (parasitoid:host ratio 5 1:9), superparasitism of L. hesperus eggs was 33.3, 66.7, and 82.2% after exposure for 2, 6,...

the tomato leafminer, tuta absoluta (meyrick), is one of the most important pests of tomato, solanum lycopersicum l., in iran. in this research, natural enemies diversity of t. absoluta and proportion of predators or parasitoids density to moth eggs or larvae density on five tomato cultivars including super strain b, super chief, mobil, korral, and early urbana y were studied in an experimental...

In sexual organisms, low population density can result in mating failures and subsequently yields a low population growth rate and high chance of extinction. For species that are in tight interaction, as in host-parasitoid systems, population dynamics are primarily constrained by demographic interdependences, so that mating failures may have much more intricate consequences. Our main objective ...

Natural parasitoid systems exhibit considerable variation in their life history properties yet little is known about the effects of development time on parasitoid fitness or of the conditions that might select for rapid development at the expense of reduced parasitoid growth. In this study the techniques of adaptive dynamics are applied to a discrete time host-parasitoid model to examine the ev...

pauesia antennata mukerji (hymenoptera, braconidae) as the unique parasitoid of the giant brown peach aphid, pterochloroides persiace cholodkovsky (hemiptera, aphididae) is considered to be the most effective biological control agent of this pest. in this study, the assessment of selected biological parameters of p. antennata demonstrated that the longevity of mature parasitoid was 3.90 ± 0.22,...

Although density-dependent benefits to hemipterans from ant tending have been measured many times, few studies have focused on integrated effects such as interactions between ant tending, natural enemy density, and hemipteran density. In this study, we tested whether the invasive mealybug Phenacoccus solenopsis is affected by tending by ghost ants (Tapinoma melanocephalum), the presence of para...