The goal of this research was to evaluate the quality of populations of Trichogramma pretiosum Riley, in the laboratory, by using the flight test developed by the International Organization of Biological Control (IOBC). The parasitoids were obtained from eggs of Helicoverpa zea (Bod.) collected in corn fields, and kept in the laboratory on eggs of the factitious host Anagasta kuehniella (Zeller). First, we made a comparison between the standard model developed by the IOBC (with some modifications), and a customized model named ESALQ. For each model, we evaluated the quality of three populations of T. pretiosum, kept in the laboratory for 3, 35 and 72 generations. Both models showed no difference in the quality of the studied populations, based on the percentage of parasitoids that showed initial flight activity after emergence. The ESALQ model allowed better discrimination between "non-flyers" and "flyers". Second, we monitored the quality of three sexual populations of T. pretiosum, started with one, five and ten couples, during 21 generations, using the ESALQ model. The population started with a single couple showed an inferior quality when compared to the populations started with five and ten couples. The flight test was highly efficient to determine the quality of T. pretiosum populations, under laboratory conditions, and the modifications made in the standard model provided a better discrimination of flyers and non-flyers of the parasitoid. Thus, we indicate the ESALQ model as a substitute of the standard model, developed by the IOBC.
Biological control; quality control; mass rearing
