Bioefficacy of different formulations of Metarhizium anisopliae (Metchnikoff) Sorokin IOF strain (KF408075) against Oryctus rhinoceros (Linnaeus) in vitro condition

Abstract

The laboratory experiments were carriedout at the Institute of Organic Farming (IOF), UAS, Dharwad, during 2014-2015 to study the bioefficacy of different formulations of Metarhizium anisopliae against coconut rhinoceros grubs, Oryctus rhinoceros (Linnaeus). Among different oil based formulation, rice bran oil (60%) + corn oil (40%) formulation found least LC50 value (1.99 x 106 cfu/ml) at 432 h. In granular and wettable powder formulation, the granular formulation recorded least LC50 value 0.44 x 108 cfu/g at 240 h. The medean lethal time (LT50) of different oil based formulations, the rice bran oil (60%) + corn oil (40%) formulation @ 3 x 106 cfu / ml recorded lower LT50 value of 319.89 h (13.32 days). Among granular and wettable powder formulation, the granular formulation @ 5 x 108 cfu / g, proved most effective exhibiting 50 per cent of mortality with least LT50 value of 162.88 h (6.78 days).