This study was conducted
to evaluate Toxicity and repellent effects of two locally available plants
namely Solanum melongena (Solanacae) and Cyperus rotundus (Cyperacae)
against adults of Sitophilus Oryzae. The plant extracts were applied at
five concentrations on rice grains which 2.5, 5, 10, 25 and 50%) for each.. Adult
insects were exposed to treated rice grains and mortality was calculated after   1, 2, 6, 10 and 17 days of exposure. The
results indicated that the toxic and repellent effects were proportional to
concentrations and time intervals. Higher concentrations had stronger toxicity and
repellent effects than lower concentrations. Rice grains weevils which were
treated with two plant extracts exhibited significant mortality percentage of 76.6
and 46.66, respectively, after 17 days at 50% concentration. These indicated
that S. melongena was more toxic than C. rotundus   against
adult insects. The highest concentrations of 50% extracts giving 56.6 and 51.6
repellency respectively in both plant extracts percentage