Seven experimental fields were installed in altitudes varying from 200 to 1050 meters, located in Afonso Cláudio and Venda Nova do Imigrante in Espírito Santo State, Brazil. The evaluations of Trichogramma presence were done to determine the native species, know the natural parasitism rate in order to use the obtained results in programs of pest management of Tuta absoluta. In all commercial tomato fields only Trichogramma pretiosum Riley was collected. In the first year the medium number of egg-cards sample with parasitism, as well as the medium number of parasitized eggs, presented an inverse relationship when compared to the areas of altitude between 200 and 850 meters. In the lower areas (200, 380 and 450 m) a constant presence of parasitoid eggs in all the inspected areas was observed. In the second year the behavior differed from that of the first year. The medium values of the inferior parameters, with the medium number of eggs parasitized by cards, were reduced by half. The two year results showed that the aggressiveness of the T. pretiosum strains was differentiated depending on the area.
Lycopersicon esculentum; T. pretiosum; biological control; Trichogrammatidae; parasitoid eggs
