Occurrence of entomopathogenic fungi in atlantic forest soils

Abstract

Abstract Knowledge of the composition and distribution of native entomopathogenic fungal species are essential to evaluate the potential of biological control in a given ecosystem. In this study, 10 soil samples were collected in two seasons (dry and rainy) in the Curió Municipal Natural Park in Paracambi and the pres- ence of entomopathogenic fungi species was evaluated. The isolation was carried out using two methods: the bait method with Galleria mellonella and Tenebrio molitor larvae and the selective media Agar Potato Dextrose method supplemented with insect integument (PDA+IT) and Martin medium. A total of 216 isolates of entomopathogenic fungi were isolated. The bait method with larvae collected 88.0%, while the PDA+IT media and Martin method caught 12.0%. The most predominant species was Beauveria bassiana isolated with G. mellonella in the dry (36.0%) and in the rainy (36.0%) season. Metarhizium anisopliae was isolated, mostly in T. molitor in the dry (33.3%) and in the rainy (32.0%) season. Beauveria bassiana was less prevalent in the Martin medium, occurring 13.3% in the dry and 33.3% in the rainy season. The occurrence of B. bassiana using the PDA+IT medium was 33.3% in the dry and 20.0% in the rainy season. The higher incidence of M. anisopliae (26.7%) was in the rainy season with the PDA+IT medium. The higher incidence of entomopathogenic fungi was observed using the bait method with high frequencies of B. bassiana and M. anisopliae. The bait method with G. mellonella and T. molitor is a sensitive method for the isolation of entomopathogenic fungi in soil