Field Evaluation of Metarhizium anisopliae (Metschnikoff) Sorokin against White Grubs in Sugarcane and Arecanut

摘要

Field experiments against root grubs in sugarcane and arecanut were laid out at Agricultural Research Station, Sankeshwar, Belgaum district and Sugavi village in Sirsi taluk of Uttar Kannada district of Karnataka, India, respectively. Application of Metarhizium anisopliae (Metschnikoff) Sorokin (Ma-1) against sugarcane white grub, Holotrichia serrata (Hope) at 1x1013 conidia ha-1 was found next best to chlorpyriphos and registered 91.95% reduction in grub population (60 DAT). The highest cane yield was recorded when M. anisopliae was applied @ 1x1013 conidia ha-1 (94.21t ha-1) and it was on par with chlorpyriphos @ 3lit a.i. ha-1 (93.76t ha-1). However, incremental benefit-cost ratio (IBCR) was high with higher dose of mycopathogen (7.83) followed by drenching of chlorpyriphos @ 2lit a.i. ha-1 (6.09). Application of M. anisopliae (Ma-1) against arecanut white grub, Leucopholis lepidophora (Blanchard) @ 2x1013 conidia ha-1 recorded 77.10% reduction in grub population and was next best to chlorpyriphos drenching @ 1 lit. a.i. ha-1 (96.80%).