Effects of Six Botanical Plant Powder Extracts on the Control of Rice Weevil, Sitophilus Oryzae L. in Stored Rice Grains

In the present study, powder prepared from parts of six indigenous botanical plants in Manipur, India (Melia azadarach, Perthenium hysterophorus, Phlogocanthus thyrsiflorus, Vitex trifolia, Zanthoxylum acanthopodium and Azadirachta indica ) were tested for their efficacy on mortality, rate of adult emergence, grain damage effect against rice weevil, Sitophilus oryzae on rice grain. Adult insects were exposed to 5 g powder extracts treated rice grain 20 g and mortality was assessed after 7, 14, 21, 28 and 35 days. The result obtained showed that plant powder M. azadarach recorded the highest mean mortality of 80.54% at 35 days after treatment (DAT) when compared with other treatments, followed by Z. acanthopodium and A. indica showed 70.74% mortality whereas P. hysterophorus and P. thyrsiflorus was found less effective 56.11 % mortality followed by Vitex trifolia (36.66%) mortality. The plant powder A. indica was found highly effective in prohibiting the adult emergence and reduction in grain damage per cent over other treatment. It was concluded that M. azadarach, A. indica and Z. acanthopodium could be used for the protection of stored rice from infestations of S. oryzae.