Entomopathogenic fungi on the control of Sphenophorus levis in sugarcane crop

Resumo

Brazil is the largest producer of sugarcane crop in the world,but its production can be highly affected by the pest Sphenophorus levis. The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana can be used for the control of this pest, but are not always effective in the field, lacking information on application methods, doses and formulations. We evaluate the efficacy of M. anisopliae IBCB 425 and B.bassiana IBCB 66 in controlling S. levis and other soil pests at sugarcane crop. The bioassay was conducted in a split plot design, where each of the 4 treatments were repeated 5 times and distributed over an area of 5.000 m². The treatments for both fungi consisted of: Wettable powder (WP) formulation 225 g conidia ha^-1, WP formulation 450 g conidia ha^-1, granule (GR) formulation 10 Kg ha^-1 and Control (no fungal application). WP fungi formulations were applied to the ratoon with a tractor using a ratoon cutter and an pesticide applicator. The GR fungi formulation was manually applied on the ratoons. The evaluations were performed after 21, 60 and 100 days of fungi application. B. Bassiana fungus reduced the pest population but did not differ from the control, however for M. Anisopliae fungus there were significant differences between treatments on damaged stems. The fungus M. anisopliae was effective in controlling S. levis larvae and adults in the field and WP formulation had faster action than the GR, the dose of 225 g conidia ha^-1 was enought to reduce S. levis population.