Laboratory (25ºC, 70% UR and photoperiod of 12 hours) studies were conducted to evaluate the response of Trichogramma atopovirilia Oatman & Platner female to the increase of its host [Helicoverpa zea (Boddie)] egg densities. One, three, five and 10 females received, 15, 30, 60, 90, 120 e 150 eggs, for a period of 24 h. Results indicated mutual interference of both parasitoid and host, when three or more females were confined inside the vials in low densities of host eggs resulting in a lower number of parasitized eggs/female. With at least 120 host eggs (minimum of 12 eggs available/female) no mutual interference was observed. Quadratic responses were verified to the total number of parasitized eggs with the increase of egg density, with five or more parasitoids/vial. Percent parasitism did not increase with the increment in egg density.
Insecta; biological control; parasitoid