Pathogenicity of Natural Preparations of the Entomopathogenic Fungus Beauveria hassiana (Bals) Vuill on the Imported Cabbage Worm Pieris rapae L. (Lepidoptera: Pieridae)(1)

Abstract

The fungus B. bassiana was isolated from naturally infected larvae of leopard moth Zeuzera pyrina L. The isolate designated as strain LARC/FB 192 was found pathogenic to the imported cabbage worm Pieris rapae L.

Pathogenicity of this natural isolate on the larvae of P. rapae was evaluated. The time required to express its action was found to be related to the form used. Beauveria bassiana mycosis of P. rapae larvae 10 days after applying the fungus orally or topically as a dry powder and in a liquid form led to mortality rates of 89.15%, 83.38% and 91.63%, respectively. Applying the pathogen in a liquid form (SPS) appeared to be a better choice as judged by the significant differences in the average percent mortality rates at any given time interval.