జర్నల్ ఆఫ్ ప్లాంట్ పాథాలజీ & మైక్రోబయాలజీ

నైరూప్య

Pathogenicity of Three Entomopathogenic Fungi against Helicoverpa armigera

N. Revathi, G. Ravikumar, M. Kalaiselvi, D. Gomathi and C. Uma

The agricultural pests and pathogens known so far include 2,000 species of insects and 800 fungi. Among the insect pests Helicoverpa armigera, a lepidopteran insect causes more than 50% loss in yield of important crops such as cotton, pulses, vegetables and sunflower in India. In recent years, agricultural production of pulses repeatedly have suffered average yield loss of about 67% due to high levels of insecticide resistance in H.armigera. In the present study, Metarhizium anisopliae, Beauveria bassiana, and Nomuraea rileyi are used to control the insect pest. The mass production of cell wall was carried out by two stage fermentation for the production of various enzyme and its inhibitors. The M. anisopliae and B. bassiana isolates from fields showed greater than 70% mortality of H. arimgera in the bioassay the percentage mortality declined; there was a decrease in the enzyme activities of B. bassiana. N. rileyi isolates did not exhibit detectable chitinase levels even up to 120 h.