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Two indigenous entomofungal strains each of Beauveria bassiana and Metarhizium anisopliae were tested for their pathogenic effect on Aak grasshopper, Poekilocerus pictus, Fabricus, 1775 (Orthoptera: Acrididea) under laboratory conditions. Among the four isolates tested, M. anisopliae ICAR-NBAIR Ma-4 and ICAR-NBAIR Ma-35 caused 100 and 90% mortality, respectively, whereas B. bassiana ICAR-NBAIR Bb-78 and ICAR-NBAIR Bb-45 showed 40 and 14% mortality, respectively. ICAR-NBAIR Ma-4 and ICAR-NBAIR Ma-35 isolates were further tested on eggs of grasshoppers which showed 72.7 and 59.8% mortality respectively. Dose and time mortality studies with ICAR-NBAIR Ma-4 showed LC50 value of 1.52 × 103 spores/ml and LT50 of 68.17 h at dose of 1 × 108 spores/ml. ICAR-NBAIR Ma-35 showed LC50 value of 2.09 × 103 spores/ml and LT50 of 87.10 h at dose of 1 × 108 spores/ml. The use of isolate ICAR-NBAIR Ma-4 as a potential control agent of Poekilocerus pictus with a lower LC50 which killed faster half of Poekilocerus pictus individuals. This isolate can be further tested against the devastating invasive desert locust, Schistocerca gregaria for its management on the eggs and early hopper stages. [ABSTRACT FROM AUTHOR]

Ten indigenous entomofungal strains of Beauveria bassiana, Metarhizium anisopliae, and M. rileyi were evaluated against 2nd instar larvae of the maize fall armyworm (FAW) Spodptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in a laboratory bioassay. Among the ten strains tested, M. anisopliae ICAR-NBAIR Ma-35 caused 67.8% mortality, followed by B. bassiana ICAR-NBAIR Bb-45 with 64.3%, and ICAR-NBAIR Bb-11 with 57.1% mortality. Rest of the isolates showed 10.7–28.6% mortality. ICAR-NBAIR Ma-35 showed LC50 of 1.1 × 107 spores/ml and LT50 at 1 × 108 spores/ml is 86.04 h and ICAR-NBAIR Bb-45 showed LC50 of 1.9 × 107 spores/ml and LT50 at 1 × 108 spores/ml is 88.30 h. Field evaluation with these two promising strains were conducted against maize fall armyworm for 2 years (2018 and 2019) at ICAR-National Bureau of Agricultural Insect Resources experimental farm, Bengaluru, Karnataka, India. Field trial results indicated 68 and 69% reduction of FAW infestation and 55 and 62% increase in yield in the plots treated with M. anisopliae ICAR-NBAIR Ma-35/B. bassiana ICAR-NBAIR Bb-45, respectively, during 2018. In 2019, 70 and 76% reduction of FAW infestation and 44 and 55% increase in yield were observed in the plots treated with these two entomofungal pathogens, respectively. [ABSTRACT FROM AUTHOR]