Toxicidal efficacy of <i>Azadirachta indica </i>(A. Juss) kernel and <i>Ocimum basilicum</i> (Linn.) leaf against maize grain weevil (<i>Sitophilus zeamais </i>Motsch.)

Abstract

Studies were carried out to determine the efficacy of the kernel powder of Azadirachta indica, and leaves of Ocimum basilicum against Sitophilus zeamais. 0.5, 1.0, 1.5 and 2.0g of powder of A. indica, and O. basilicum /50g of maize grains, were tested along with the synthetic conventional insecticide, Coopex (0.25g/50g) under laboratory conditions (28-32^oC and 65-70% r.h.). In all trials, the mortality among adults of S. zeamais reared on maize treated with the powders of A. indica and O. basilicum was observed to be high (55%/0.5 g). Percentage mortality among adults was significantly (P<0.05) different from the untreated (control). Thus, both the plant materials were found to significantly affect the survival of the S. zeamais at different concentration rates. Effect of the powders on the emergence of adult S. zeamais was significant (P<0.05) and reduced the F1 progeny emergence.