Evaluation of biorationals and new molecules against root grubs in onion ecosystem

Abstract

The field experiment was conducted in endemic areas of Bagalkot district, Karnataka during Kharif 2017-18, to study the efficacy of biorationals and newer molecules against root grubs in onion ecosystem. Among the new molecules tested against root grubs, both chlorantraniliprole 18.5 SC at 400 ml per hectare and flubendiamide 480 SC at 400 ml per hectare registered the minimum per cent mortality of onion plants (1.30% and 2.57%, respectively), minimum number of root grub population per square metre area (0.53 and 1.00, respectively) and maximum yield levels (43.83 and 39.68 t/ha, respectively) as compared to standard check (Chlorpyriphos 20 EC @ 10 larvae / ha). However, based on cost economics, chlorantraniliprole 18.5 SC at 400 ml per hectare registered the maximum net returns (Rs. 3,63,571/ha) with highest B:C ratio (5.86) compared to flubendiamide 480 SC suggesting that chlorantraniliprole 18.5 SC at 400 ml per hectare as most cost effective, ecofriendly and easily adoptable by the farming community.