Bioassay of Metarrhizium Anisopliae (Metchnikoff) Against Leaf Eating Caterpillar Helicoverpa Armigera (Hubner) Ingle R. W., Jayaraman G, Deshmukh V.V. Department of Plant Pathology, Dr. Panjabrao Deshmukh Knshi Vidhyapeeth, Akola (MS), 444104, India. Abstract Pathogenic ability studies of five different isolates of Metarrhizium anisopliae (Metchnikoff) was carried out against the leaf eating caterpillar Helicoverpa armigera (Hubner). The LC50 values of isolates Ma PDBC, Ma-IIHR, Ma-TNAU, Ma-AKL and Ma-ITCC on topical application of fungal spore suspension were 4.64×105 7.03×l05, 3.19×106, 6.73×l06 and 8.62×l06 spores ml−1, respectively; onleaf dip method were 1.33×l06. 8.68×l06, 2.93×l07, 5.03×l07 and 7.93×l07 spores ml−1, respectively; and on both topical application and leaf dip method were 1.88×l04, 6.64×l04, 1.39×l05, 5.54×l06 and 7.62×l05 spores ml−1, respectively. The LC50 values of five different isolates were varied with virulence of isolates and also with spore concentrations. Ma-PDBC was found most virulent, followed by Ma IIHK and Ma-TNAU where as Ma-ITCC and Ma-AKL was found less virulent. Combination of topical application and leaf dip method was found effective for pathogenicity test followed by topical application method. Top Keywords Helicoverpa armigera, Metarrhizium anisopliae. Top |