Potential food substances were evaluated for their effect onTrichogrammafecundity and longevity. The materials tested included 5 protein diets with an agar base, glucose, fructose, cotton-plant nectar, honey, beef extract in various combinations with honey, and water. The protein formulations and the water did not increase adult fecundity and longevity vs. unfedTrichogramma. Fructose, cotton-plant nectar, honey, and beef extract in various combinations with honey were equally nutritious. There were no significant differences in fecundity and longevity in an experiment comparing unfedTrichogrammavs. ones observed to have fed during a 1.5-h period on honey, 1.0% beef extract, and fructose.