Synergistic Interaction of Bacillus thuringiensis Berliner with some Insecticides against the Tobacco Caterpillar, Spodoptera litura Fabricius on Cauliflower

Abstract

Pot culture studies on the interspecific economic synergism between Bacillus thuringiensis Berliner (B.t.) and endosulfan, phosalone and fenvalerate against the tobacco caterpillar, Spodoptera litura Fabricius showed that combination of fenvalerate (0.01 %) with B.t. (4.40 x 108 viable spores/ml) was significantly superior to others in inflicting mortality/deformity in the insect pest. The combination of the bacterium with phosalone and endosulfan also proved effective against the insect pest. B.t. at 4.40 x 108 and 2.20 x 108 viable spores/ml produced a mortality of 58.37 and 38.22 per cent respectively, while the bacterium in combination with insecticides caused mortality/deformity in the pest to the extent of 53.99 to 96.27 percent indicating potentiating synergism.