Overview

The rice weevil, S. oryzae is perhaps the most destructive pest of stored grains and products of cereals (Pruthi and Singh, 1948). It was reported that apart from rice it also attacks the stored grains of wheat, maize and sorghum. Its larvae and adults are internal feeder and cause a serious quantitative as well as qualitative loss to cereals grains. The rice weevil is a cosmopolitan insect originating supposedly in India and spreading all around the world through infested and ship-transported grains (Metcalf and Flint (1962). The rice weevil (S. oryzae) is considered a primary stored-grain insect pest in warm climate areas including India. Seed is the most vital and important input for crop production. It is necessary to protect the seeds through locally available plant products which are eco-friendly too. At present, many farmers use synthetic pesticides for protecting their stored grains. However, synthetic pesticides have a number of adverse-effects such as poisoning among handlers, toxic residues in food and feedstuff, ecological disruption as well as chronic and genetic illness (Dubey et al., 2007; Kumar et al., 2007).