Mitul Karkar
Scientific Tracks Abstracts: Agrotechnol
Investigations on bio- efficacy of Beauveria bassiana (Balsamo) Vuillemin against Helicoverpa armigera (Hubner) infesting pigeonpea were carried out at the Agronomy farm and Department of Entomology, College of Agriculture, Junagadh Agricultural University, Junagadh, Gujarat during kharif 2011. The study revealed that the treatments of polytrin-C 0.044 per cent, chlorpyriphos 0.05 per cent and acephate 0.15 per cent were found the most toxic to the H. armigera larvae . The next best treatments were Bb at 1.25 kg/ha + polytrin-C 0.022 per cent and Bb at 1.25 kg/ha + chlorpyriphos 0.025 per cent. The bio-pesticide B. bassiana alone showed the toxicity from 3 rd day of application and increased drastically in subsequent period up to 15 th day of application and found more or less compatible with either insecticides. The B. bassiana at 3.5 g/litre proved to be the most effective dose among five doses tested against 3 rd instar larvae of H. armigera under laboratory condition. Laboratory investigation on compatibility of B. bassiana fungus with different seven insecticides revealed that the insecticides spinosad, indoxacarb, monocrotophos and acephate were most compatible with entomogenous fungus, B. bassiana . Chlorpyriphos, polytrin- C and azadirachtin were found less compatible with entomogenous fungus, B. bassiana