In VitroCulture ofTrichogrammaSpp. on Artificial Diets Containing Yeast Extract and Ultracentrifuged Chicken Egg Yolk but Devoid of Insect Components

Trichogramma minutumRiley andTrichogramma brassicaeBezdenko (Hymenoptera: Trichogrammatidae) were culturedin vitrofrom eggs to adults on artificial diets, which contained no insect components. The diets contained ultracentrifuged chicken egg yolk, milk, Graceʹs insect medium, and yeast extract. The most important components were the yeast extract and ultracentrifuged chicken egg yolk. Addition of the sediment of ultracentrifuged chicken egg yolk to a diet containing yeast extract enhanced yield of pupae 2.2-fold and of adults 2.7-fold. Based on numbers of first instars and pupae, respectively, the best diet produced 94% pupae and 28% adults ofT. minutum.