Completely parthenogenetic Trichogramma wasps can be rendered permanently bisexual by treatment with three different antibiotics or high temperatures. The evidence strongly suggests that maternally inherited microorganisms cause parthenogenesis in these wasps. Theories predict female-biased sex ratio in offspring under the influence of maternally inherited symbionts, but extreme sex ratios of 1...

The smallest insects are comparable in size to unicellular organisms. Thus, their size affects their structure not only at the organ level, but also at the cellular level. Here we report the first finding of animals with an almost entirely anucleate nervous system. Adults of the smallest flying insects of the parasitic wasp genus Megaphragma (Hymenoptera: Trichogrammatidae) have only 339-372 nu...

Parasitoids learn olfactory and visual cues that are associated with their hosts, and use these cues to forage more efficiently. Classical conditioning theory predicts that encounters with high-quality hosts will lead to better learning of host-associated cues than encounters with low-quality hosts. We tested this prediction in a two-phase laboratory experiment with the parasitoid Trichogramma ...

Trichogramma Westwood (Hymenoptera: Trichogrammatidae) cause high mortality rates in the potentially resistant pest species, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), and are considered integral to the resistance management plan for Bacillus thuringiensis transgenic cotton, Gossypium hirsutum L., production in the Ord River Irrigation Area (ORIA), WesternAustralia.Measured as perc...

Egg parasitoids of the corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), were surveyed exposing sentinel eggs of the leafhopper along a latitudinal transect of 600 km in Argentina, the southernmost area of its distribution range. Four parasitoid species were obtained: the mymarids Anagrus breviphragma Soyka (Hymenoptera: Mymaridae), Anagrus flaveolus Waterhouse, a...

Bioassay was conducted with nine botanical extracts at various concentrations viz., azadirachtin 300ppm, 1500ppm, 3000ppm, 10000ppm, neem seed oil 1%, 2%, 3%, extract 5% and dashparniark 4% on Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) in completely randomized design. Assessment of these % parasitization, reduction parasitism adult emergence T. Corcyra eggs done. The r...

JACI MENDES VIEIRA1, RANYSE B. QUERINO2, FERNANDO L. CÔNSOLI1 & ROBERTO A. ZUCCHI1 1Departamento de Entomologia e Acarologia, ESALQ, Universidade de São Paulo, Caixa Postal 9, 13418-900 Piracicaba, SP, Brazil. E-mail: [email protected]; [email protected]; [email protected] 2Empresa Brasileira de Pesquisa Agropecuária, Embrapa Meio-Norte, 64006-220 Teresina, Piauí, Brazil. E-mail: ranyse.silv...