Bioefficacy of Different Insecticides/Biopesticides against Plutella xylostella in Cabbage

An experiment was conducted to evaluate the bioefficacy of different insecticides/biopesticides against Plutella xylostella L. in cabbageunder field conditions during Rabi season 2006–07. Among all the tested insecticides, spinosad 0.002 per cent proved to be the most effective in reducing the larval population of P. xylostella followed by indoxacarb 0.01 per cent and Dipel 0.2 per cent, respectively. During the study endosulfan 0.07 per cent, malathion 0.05 per cent and oxy-demeton-methyl 0.025 per centwere found moderately effective against P. xylostella. The treatments of Beauveria bassiana (0.40 per cent), NSKE (3.0 per cent) and azadirachtin (0.5 percent) were found least effective. The highest yield of cabbage heads was recorded in spinosad (233.5 q ha−1) followed by indoxacarb (226.8 q ha−1) and B. thuringiensis (224.9 q ha−1). The incremental C:B ratio of 90.5 was obtained from the treatment of spinosad followed by oxy-demeton-methyl (54.2), endosulfan (48.4), malathion (45.1),B. thuringiensis(18.2) and indoxacarb (17.6).