Evaluation of Certain Plant Leaf Powders and Aqueous Extracts against Maize Weevil, Sitophilus zeamais Motsch. (Coleoptera: Curculionidae)

Awoke Yohannes ； Genet Asayew ； Getachew Melaku ； Mulugeta Derbew ； Sirgota Kedir ； Nagappan Raja

《Asian Journal of Agricultural Sciences》 6卷3期 (2014/05) Pp. 83-88

並列摘要

Aim of the present study was to evaluate powders and aqueous extracts of Melia azedarach, Mentha piperita, Phytolacca dodecandra, Schinus molle and Xanthium strumarium leaves against maize weevil Sitophilus zeamais. Repellent activity of plant powders were evaluated by mixing 0.625, 1.25, 2.5, 5 and 10 g of powder per 100 g of clean uninfested maize seeds individually in separate plastic container. The numbers of insects moving outside the container were recorded at 24 h and 48 h post exposure period and percentage of repellent activity was calculated. The insect mortality was recorded at 5 days, 10 days and 15 days post exposure period and percentage of insect mortality was calculated. In addition, aqueous solutions were prepared by mixing 0.0625, 0.125, 0.25, 0.5 and 1 g of plant powder with 10 mL of water and tested for their insecticidal activity by topical application method. Total numbers of dead insects were counted for every 24 h up to 96 h post exposure period and percentage of insect mortality was calculated. Plant powders admixed with maize seed failed to show satisfactory level of repellent activity. Maize seed admixed with 10 g of Mentha leaf powder showed 93.3% mortality followed by Schinus (90%) and Phytolacca (90%) 5 days of post exposure period. After 15 days, 100% mortality recorded in Mentha, Melia and Schinus leaf powder mixed with 10/100 g of maize seeds followed by Phytolacca (90%) and Xanthium (86.6%). The topical application of aqueous extracts did not show insecticidal activity at satisfactory level. In general, application of Melia, Mentha and Schinus leaf powders proved to be effective against Sitophilus zeamais.

並列關鍵字

Insecticidal activity ； Melia azedarach ； Mentha piperita ； Phytolacca dodecandra ； plant extracts ； repellent activity ； Schinus molle ； Sitophilus zeamais ； Xanthium strumarium