Pathogenicity of Metarhizium rileyi (Farlow) against Spodoptera frugiperda (JE Smith) and its compatibility with insecticide and bioagents

Metarhizium rileyi isolates (M. rileyi NIPHM, M. rileyi MTCC 4254 and M. rileyi MTCC 10395) were evaluated against S. frugiperda larvae to identify virulent strain and to study its bio-safety with Trichogramma chilonis, Bacillus thuringiensis and chlorantraniliprole 18.5% SC. The M. rileyi bioformulation MTCC 4254 recorded maximum larval mortality (50.0%) and was at par with M. rileyi NIPHM (48.3%) (12 g L^-1). M. rileyi formulations recorded minimum reduction in adult emergence of T. chilonis over control (17.1%) in M. rileyi NIPHM. All bioformulations of M. rileyi recorded less than 30% reduction in adult emergence of T. chilonis and were found safe. Compatibility studies of M. rileyi MTCC 4254 with Bacillus thuringiensis Delfin WG recorded minimum growth reduction over control (29.9%). However, 50.7% growth reduction over control was recorded with chlorantraniliprole 18.5% SC (0.4 mL L^-1). This study highlights that M. rileyi MTCC 4254 is pathogenic and compatible with T. chilonis and Delfin WG indicating M. rileyi, B. thuringiensis Delfin WG and T. chilonis could be integrated as components in integrated pest management programme (IPM) for effective management of S. frugiperda in field conditions.