Management of rice weevil, Sitophilus oryzae (Coleoptera: Curculionidae) in stored rice grains using certain indigenous plant materials

Abstract

Food grains are very essential in daily diet of population worldwide. There are huge qualitative and quantitative losses of rice grains in storages due to attack of rice weevil, Sitophilus oryzea. Safe alternatives to traditional chemicals/fumigants are a dire need to combat such losses. This pest regularly causes severe damage to stored products which may be 5 to 10 percent in temperate and 20 to 30 percent in tropical areas. Different indigenous plant extracts including Cymbopogan citrate, Azadirachta indica, Eucalyptus grandis, and cannabis sativa were used against this pest under laboratory conditions. Parameters of study were adult mortality rate, grains weight loss and F₁ adult emergence. The maximum mortality of pest was observed in grains treated with A. indica that is 66% and the minimum mortality was found in Cannabis sativum that is 55%. The maximum weight loss (47%) was recorded in grains treated with A. indica as compared to other plants extracts.