Evaluation of new molecules for diamond back moth management in cabbage

The bioefficacy of a new molecule, Spinosad along with recommended insecticides and Bt formulation was evaluated against diamondback moth (DBM), Plutella xylostella L., infesting cabbage under field condition during 2001 and 2002. Two sprays of each treatment was applied at attainment of ETL (2–3 DBM larvae/plant). At 3 days after first treatment, lowest larval population (1.6/plant) was recorded in Spinosad (@ 20 g ai/ha) treated plot being at par with other Spinosad and Bt treatments. The larval population during different post-treatment periods indicated the superiority of Spinosad in controlling DBM larvae even @ 15 g ai/ha. The persistency of this insecticide on the basis of larval infestation was recorded to be 10 days after treatment.