The objective of this work was to accomplish the quality control of populations of Trichogramma pretiosum, on the basis of biological, genetic and behavioural evaluations, considering related aspects, mainly, to the size of the founder population and the type of reproduction of the parasitoids. The parasitoids were obtained through field collections, on eggs of Helicoverpa zea, in corn, and kept in laboratory in eggs of the alternative host Anagasta kuehniella. Virgin males and females, derived from different places, were selected and used in controlled crossings to start the laboratory populations. The populations were submitted to quality evaluations, monitoring: the number of parasitized eggs, emergence rate, sex ratio, longevity, deformation, flight activity, besides the effective number of individuals and the coefficient of inbreeeding. It was concluded that the inbreeding is not a limiting factor for T. pretiosum mass rearing, being possible to start rearings using only one couple, and keeping them for, at least, 25 generations, without affecting its quality. Sexual populations of T. pretiosum show significant superiority, related to the parasitism and the ability to support adversities in the rearing process, when compared to thelytokous populations. The longevity and the parasitism were adequate variables to detect quality losses in the laboratory rearings; while the emergence rate, the sex ratio and the percentage of adults deformation, did not show an accuracy indication of the quality of the bred parasitoids. The flight test was a highly efficient method in the determination of the quality of T. pretiosum populations, and the ESALQ model, proposed in the current research, provided a better separation of flyers and non-flyers parasitoids, being to be indicated as substitute of the standard model, recommended by the IOBC.
Species 1: Hymenoptera Trichogrammatidae Trichogramma pretiosum
Keywords: biological control, mass rearing
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA