This work aimed to evaluate the effects of Metarhizium anisopliae on Diatraea flavipennella and investigate their immune response. Was observed the effect of M. anisopliae against larvae of D. flavipennella sprayed at concentrations of 10 3 , 10 4 , 10 5 conidia / mL, in which showed differences relative the larval period, extending up to 72.0 days in treatment and 25.0 days in the control. The results for hemocytes revealed that the most frequent cells when sprayed at the concentrations of 10 3 , 10 5 , 10 7 conidia / mL were the prohemocytes, spherulocytes, plasmatocytes and granulocytes in relation to adipohemocytes and oenocytoids. The level of nitric oxide was different between the control and the concentration 10 7 spores / mL (24), while the activity of phenoloxidase was similar among treatments in 24 and higher concentration 10 7 spores / mL (60h). In biochemical profile of hemocytes was a change in carbohydrates, lipids and proteins in response to the fungus. The results indicate that the fungus M. anisopliae can be used in the Integrated Management of D. flavipennella by presenting pathogenicity and interfere with their development even when exposed to small concentrations.

Biological control using the parasitoid Cotesia flavipes (Cam.) is one of the main components in the integrated management of the sugarcane moth borer Diatraea spp. Besides this parasitoid, the entomopathogenic fungi Beauveria bassiana (Bals.) Vuill and Metarhizium anisopliae (Metsch.) Sorok. are used to control sugarcane pests, and they can be found naturally parasitizing caterpillars. This study aimed to evaluate the effects of M. anisopliae and B. bassiana on different developmental stages of the C. flavipes parasitoid on Diatraea flavipennella (Box). The experiments were carried at laboratory with isolates PL 43 of M. anisopliae and ESALQ 447 of B. bassiana were applied to the parasitoid at the immature and adult phases. No negative effects were observed on the larval development of C. flavipes, and it could complete its development on caterpillars of D. flavipennella treated with fungi. The fungi did not cause pupal mortality. However, B. bassiana caused high mortality in the adult parasitoid (76%). The fungi had negative effects on parasitoids when applied during certain developmental stages of C. flavipes.