Avaliação da patogenicidade de Beauveria bassiana (bals.) vuill e Metarhizium anisopliae (metsch.) sorokin para o controle de Atta sexdens rubropilosa (forel, 1908) (Hymenoptera: formicidae) em condições de laboratório

Abstract

This research evaluated, under laboratory conditions, the efficiency of different isolates of entomopathogenic fungus Beauveria bassiana to control leaf-cutting ant Atta sexdens rubropilosa. Soldiers and workers were inoculated with suspensions containing 1,0 x 107, 1,0 x 108, 1,0 x 109 e 1,0 x 1010 conidia/mL, maintained in B.O.D., at 25 ± 1°C, 70% RH and 12 hours of photophase, without food. The mortality was evaluated daily, until 15 days after inoculation. The experimental delineation used was entirely randomly. The sporulation data were submitted to the analysis of variance and the TL50 values (in days) were obtained through the Probit analysis. All isolates of B. bassiana were pathogenic to insect, being workers more susceptible than soldiers. The isolates IBCB 21 and IBCB 07 were the most virulent for workers and soldiers, respectively. The isolate IBCB 21 also caused high percentages of confirmed mortality, showing potential for use in the control of A. sexdens rubropilosa.