Evaluation of newer insecticide molecules against lepidopteran pests in castor

Newer insecticide molecules were evaluated against lepidopteran pests viz. Achaea janata L., Spodoptera litura (F.) and Conogethes punctiferalis Guen. in a field experiment conducted at the Regional Agricultural Research Station, Palem on red chalka soils for two years (2010–11 and 2011–12) during the kharif season. In this experiment popular variety Haritha, was sown and ten treatments were evaluated viz. emamectin benzoate 5% SG, lufenuron 5 EC, flubendiamide 480 SC, chlorantraniliprole 18.5 SC, spinosad 0.018%, indoxacarb 0.015%, novaluron 0.01%, lambda cyhalothrin 2.5% EC, acephate 75 SP and control. The treatments were imposed twice during first week of November and December when infestation crossed above economic threshold level. Majority of the insecticides showed significant control with a single application. The treatments chlorantraniliprole (1.64 and 1.01), spinosad (1.92 and 0.92 larvae/plant) and flubendiamide (2.56 and 1.25 larvae/plant) were significantly superior for Spodoptera and castor semilooper, respectively at one day after spraying during the first spray. Lambda cyhalothrin and acephate were less effective against semilooper and recorded 1.1 and 1.25 and 1.25 and 1.58 larvae/plant respectively at one week after spraying in first and second sprays, respectively. The treatments flubendiamide (20%), chlorantraniliprole (19.3%), lambda cyhalothrin (18.3%) and acephate (26%) recorded less % damaged capsules at one week after second spray. Significantly higher seed yield was recorded with spinosad (995 kg/ha), which was at par with flubendiamide (979 kg/ha). The treatments flubendiamide (1: 5.8), spinosad (1: 5.6) and chlorantraniliprole (1: 5.3) registered the highest cost benefit ratio.