Preparation of herbal extracts and evaluation of their efficacy against rice weevil (Sitophilus oryzae L., Curculionidae; Coleoptera)
Ujjwal Sahoo, Jayita Das, Subham Saha, Sutirtha Kumar Das, Debojyoti Roy, MK Debnath and SK Sahoo
The experiment was conducted to evaluate the efficacy of Neem, Kalmegh, Cinnamon, Black pepper and Clove extract along with Diatomaceous Earth (DE) against rice weevil (Sitophilus oryzae L.) in terms of percent mortality and repellency of adult weevil at different exposure period. Maximum adult weevil mortality (49.70 to 90.15%) was noticed after 3 weeks of treatment with 60 gm of Neem, Kalmegh and Clove along with 1 gm of Diatomaceous Earth. But in case of Cinnamon and Black pepper maximum mortally of adult weevil (85.57 to 100%) was found when these were used in 40gm dose in combination with DE. In the repellency study, it was found that the treatment composed of Clove and DE registered the best result after 1 week of treatment in repelling adult rice weevil (98.80%).