Bioefficacy of newer insecticides against tobacco leaf eating caterpillar, Spodoptera litura on bidi tobacco

摘要

Tobacco is a leading commercial crop valued for its leaf containing nicotine. Spodoptera litura Fabricius (Noctuidae: Lepidoptera) is a generalist herbivore infesting more than 290 species of plants belonging to 80 to 99 families (Wu et al., 2004), causing significant damage to different types of tobacco (Rao et al., 2004). Damage due to S. litura in tobacco nursery varied from 80 to 100 per cent (Chari et al., 1994) and 10-25 per cent in the field crop (Sitaramaiah et al., 2001). Various insecticides belonging to different classes are being used for the management of S. litura all over the world but it has the ability to develop resistance to many old insecticides used for its management. High resistance to various insecticides including organophosphate, carbamates and pyrethroids in S. litura have been reported in India (Kranthi et al., 2001). Considering the above factors, the present study was conducted on the bioefficacy of insecticides against 3rd instar larvae of S. litura on bidi tobacco.