Capacity for Parasitism of Trichogramma spp. in Tomato Fruit Borer under Different Temperatures

Abstract

The parasitoid in eggs of Trichogramma genre is the most studied in the world, being bred widely and used for flooding releases. This study aimed to evaluate the capacity for parasitism of Trichogramma galloi Zucchi, 1988 (Hymenoptera: Trichogrammatidae) in Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) eggs at different temperatures. The experiment was developed at the Nucleus for Scientific and Technological Development in Phytosanitary Management (NUDEMAFI) in which the daily and accumulated biological parameters were assessed, as well as total parasitized eggs by female, sexual ratio (number of females/number of males + females), viability of the eggs (number of eggs with orifice/number of parasitized eggs x 100) and number of individuals per egg at temperatures 18, 21, 24, 27 and 30ºC. The eggs of the fruit borer were offered daily to each T. galloi female at each temperature until the death of the parasitoid could be verified. The larger number of parasitized eggs was found in the first 24 h, at temperatures 24 and 27ºC with 17 parasitized eggs. The accumulated parasitism in N. elegantalis eggs reached 80% of total parasitized eggs for each thermal range (18, 21, 24, 27 and 30ºC) on the 2nd, 3rd, 3rd, 1st and 2nd days respectively. The ideal parasitism conditions for this lineage vary between 24 and 27°C. Therefore, it is concluded that the studied T. galloi lineage has adequate biological parameters in N. elegantalis eggs, demonstrating promise in phytosanitary management of this pest.