Analysis of the Optimal Densities and Embryonic Ages of Anticarsia <i>Gemmatalis</i> Eggs for the Biological Control Agent <i>Trichogramma Atopovirilia</i>

The egg parasitoid Trichogramma atopovirilia Oatman &amp; Platner (Hymenoptera: Trichogrammatidae) is a biological control agent for the soybean (Glycine max (L.) Merril)) caterpillar Anticarsia gemmatalis Hübner (Lepidoptera: Erebidae). An appropriate proportion of eggs and the embryonic age of the host are important features for achieving good parasitism rates by these natural enemies. Thus, the objective of the present study was to analyze some biological aspects of T . atopovirilia with A . gemmatalis eggs at different densities and embryonic ages. The density and embryonic age of the A . gemmatalis eggs affected the sex ratio and the number of parasitized eggs per female, individuals per egg, and females of T . atopovirilia that emerged per treatment. However, these factors did not affect the emergence percentage. The development of T . atopovirilia was optimal with 20 and 25 A . gemmatalis eggs within 24 and 48 h of embryonic development, per female of this parasitoid.