Pathogenicity of local isolates of entomopathogenic fungi against Spilarctia oblique at Pantnagar

Abstract

The aim of the present study is to test the pathogenicity of different entomopathogenic fungal isolates against Bihar Hairy Caterpillar (Spilosoma obliqua). On the basis of preliminary bio efficacy trials on all local isolates, two most virulent isolates of each Beauveria bassiana, Metarrhizium anisopliae and Nomuraea rileyi were selected for bio efficacy studies against S. obliqua. The results on dose mortality response of S. obliqua to two isolates of B. bassiana indicated that the LC50 values of first isolate were lower than the second isolate indicating that isolate 1 as more virulent. Similarly the first isolate of M. anisopliae was found to be more virulent to S. obliqua with a lower LC50 value, Relative LC50 values between two isolates showed that second isolate was 17.8, 50 and 4.1 times more virulent than the first isolate for 4-5, 10-11 and 15-16 days old larvae. Isolate 1 of N. rileyi was more effective with lower LC50 values. S. obliqua was found to be most susceptible to B. bassiana followed by M. anisopliae and N. rileyi respectively.