Relative Efficacy and Economics of Some Insecticides for the Control of Sweet Potato Weevil
Field trials were conducted during 1984, 1985, and 1986 rainy seasons. Bioefficacy of fenvalerate and cypermethrin was evaluated for the control of sweet potato weevil, Cylas jormicarius F. In comparison with other twelve insecticides. The results indicated that dipping the cuttings before planting and spraying the crop four times, first spray one month after planting, and subsequently at 3 week intervals with cypermethrin (0.015%) or fenvalerate (0.015%) @ 375 g a.l./ha was most effective in reducing the weevil damage. Cost: benefit ratio of 1:1.9 was recorded for fenvalerate followed by cypermethrin, and fenthlon.