Bioefficacy of certain botanical crude extracts against Spodoptera litura on tomato

Spodoptera litura is a polyphagous and cosmopolitan pest. This generalist can grow and survive on wide range of plant species. It causes an estimated loss of 25.8 to 100% in crop production. Establishment of S. litura would have devastating consequences on the quantity and quality of food and fiber crops. Generally chemical pesticides are used to control the infestation of Spodoptera litura but the indiscriminate use of such pesticides develops pest resistance and adversely affected the non-target organisms. So, there is a need of environmentally safe pesticides. Secondary metabolites from plants play a key defensive role against the pests and act as antifeedant, oviposition deterrents and growth inhibitors. Three botanical extracts were used in this experiment. Hexane and ethyl acetate extract ofAcorus calamus, Solenum pseudocapsicum and Eupatoroum triplinerve were used against the Spodoptera litura. These extracts were applied after 15 days interval and the efficacy of botanicals tested against the S.litura. Results showed that all six crude extracts of botanicals performed well against the pest but hexane extract of Acorus calamus gave best results against the pest. It shows highest percentage of mortality (61.94%, 37.34%) after 1st round of treatment. Hexane extract of Acorus calamus performed well after the 2nd round of treatment with highest percentage of mortality (53.13%, 40.01%).