Biology of Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) fed transgenic maize pollen

Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) is an important natural egg parasitoids of pest insects in the agricultural environment, being used as a form of biological control, and it may be affected by the Bacillus thuringiensis (Bt) toxin present in transgenic plants widely used in Brazil. The aim of this study was to evaluate the effect of Bt maize pollen fed to adults of the parasitoid T. pretiosum Riley (Hymenoptera: Trichogrammatidae) reared in the eggs of the alternate host Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Three treatments (diets) were compared: pollen from Bt maize, pollen from non-Bt maize, and 10% honey solution (control). Each treatment consisted of 50 T. pretiosum females that were freshly emerged and mated (between 24 and 36 h old). Biological characteristics indicative of the efficiency of T. pretiosum as a biological control agent were evaluated for 4 generations. The results suggest that the consumption of pollen did not affect the evaluated biological characteristics, such as percentage of parasitism, sex ratio, and number of individuals reared per host egg, in any of 4 generations. Thus, we showed that Bt maize is compatible with the use of T. pretiosum for biological control.