Persistent Toxicity of Diamide Insecticides Against Henosepilachna vigintioctopunctata (F.) on Brinjal

The persistent toxicity (PT) of diamide insecticides viz. chlorantraniliprole and flubendiamide @0.01 and 0.008% has been determined on brinjal (Solanum melongena L.) against three days old grubs (mean grub wt.= 0.0013 g/ grub) of Henosepilachna vigintioctopunctata (F.) during May, 2019. Chlorantraniliprole @0.01% was the most persistent with a PT value of 1026.52 followed by flubendiamide @0.01% (933.2), chlorantraniliprole @0.008% (755.4) and flubendiamide @0.008% (606.58) at 24 hr after feeding (HAF). On increasing the feeding period from 24 to 48 hr on the same leaves, chlorantraniliprole @0.01% showed the maximum PT value of 1791.75 followed by flubendiamide @0.01% (1422.2), chlorantraniliprole @0.008% (1382.92) and flubendiamide @0.008% (918.58). After 72 hr of feeding on the treated leaves, chlorantraniliprole @0.01% again showed maximum PT value of 2000.0 followed by chlorantraniliprole @0.008% (1634.16), flubendiamide @0.01% (1613.26) and flubendiamide @0.008% (1400.00). The order of persistent toxicity was same on brinjal plants at 24 and 48 HAF i.e., chlorantraniliprole @0.01%> flubendiamide @0.01%> chlorantraniliprole @0.008%> flubendiamide @0.008%.