Khả năng gây bệnh của nấm ký sinh đối với thành trùng sùng khoai lang, Cylas formicarius Fabr. (Coleoptera: curculionidae)

Abstract

The pathogenicity of Metarhizium anisopliae, Beauveria bassiana and Paecilomyces sp. on the sweet potato weevil adult (SPW), Cylas formicarius (Coleoptera: Curculionidae), was investigated under laboratory condition. In laboratory condition, at a density of 108 spores/ml, the effectiveness of M. anisopliae reached 100% at 7 days after inoculation (DAI), not significantly different to that of B. bassiana (97.53%), while the effectiveness of Paecilomyces sp. reached only 31.39% at 15 DAI. Among tested densities, the effectiveness of M. anisopliae at any density from 107-109 spores/ml was not significantly different to each other from 5 DAI. M. anisopliae prepared in fresh powder type gave higher and quicker effectiveness on SPW than that of dry powder; similarly, scattering application showed higher and quicker effectiveness on SPW than that of spraying application.