Bioefficacy of entomopathogenic fungi against rice bug, Leptocorisa oratorius Fab. (Hemiptera: Alydidae)

Abstract

A study titled “Bioefficacy of entomopathogenic fungi against rice bug, Leptocorisa oratorius Fab. (Alydidae: Hemiptera)” was carried out at Dept. of Agricultural Entomology to evaluate efficacy of three entomopathogenic fungi namely Beauveria bassiana, Metarhizium anisopliae and Lecanicillium lecanii for the biocontrol of rice bug. The preliminary evaluation comprised of pot culture experiment with the fungi being applied at four different concentrations ranging from 105 to 108 spores ml-1 along with insecticide malathion 500g a.i. ha-1 and an untreated control. Mortality of rice bugs were recorded at 24h interval for 10 days. Ten days after treatment B. bassiana was the most effective among the three fungal pathogens tried, with mortality values ranging from 68.88 per cent at 105 spores per ml to the highest value of 97.77 per cent at 108 spores per ml. This was followed by malathion with 95.55 per cent and B. bassiana at 107 spores per ml with 93.33 per cent mortality respectively, all being on par with each other. M. aniospliae and L. lecanii at the rate of 108 spores per ml registered the highest mean mortality of 71.11 and 62.22 per cent respectively.