APRIMORAMENTO DA LIBERAÇÃO DE Cotesia flavipes (HYMENOPTERA: BRACONIDAE) PARA O CONTROLE DE Diatrea Sccharalis (LIPIDOPTERA: CRAMBIDAE) EM CANA-DE-AÇÚCAR

Abstract

Diatraea saccharalis (Lepidoptera: Crambidae), the sugarcane borer, causes significant damage to this crop, and the use of insecticides to control this pest is challenging due to cost and efficiency issues. These factors have motivated the search for alternative control methods, such as the use of natural enemies. In this context, the parasitoid Cotesia flavipes (Hymenoptera: Braconidae) is considered important in the management of D. saccharalis due to its efficiency. This study aimed to estimate the ideal number of C. flavipes females per D. saccharalis larva, as well as to investigate the dispersal and parasitism capacity of D. saccharalis in sugarcane. The experiments were carried out at the Legado Research and Agronomic Consulting Laboratory and in the sugarcane fields of Usina Adecoagro Vale do Ivinhema S/A, located in Dourados (MS) and Angélica (MS), respectively. The densities of 1:1, 3:1, 6:1, 9:1, and 12:1 C. flavipes females per D. saccharalis larva were evaluated. The densities of 9:1 and 12:1 showed the highest parasitism rates of 50% and 55%, respectively. In the second experiment, the dispersal and parasitism of C. flavipes females in sugarcane were investigated. The average observed dispersal was 12.6 meters, with the highest parasitism rates of 56%, 40%, and 36% at 5, 10, and 15 meters, respectively. Therefore, the results indicate that a density of 9 or 12 C. flavipes females per D. saccharalis larva is adequate for controlling D. saccharalis in sugarcane. Moreover, the dispersal of C. flavipes is around 12.6 meters, and the closer to the parasitoid release point, the higher the parasitism rate, ranging from 56% to 20% between 5m and 25m, respectively.