Plantain and banana peels as sources of insecticidal materials against callosobruchus maculatus (fabricius) and sitophilus zeamais (motschulsky).

Abstract

The effect of plantain and banana peels extracts and powders as sources of insecticidal materials against Callosobruchus maculatus and Sitophilus zeamais was investigated under ambient laboratory conditions. Ife Brown variety of cowpea and yellow maize (DMR) were used. The effect of different rates of application of extracts (0, 1.0, 0.5, 10.0ml/ 20g of seed) and powders (0, 0.4, 0.8, 2.0g/ 20g of seed) of the two plants was tested for insecticidal action against C. maculatus and S. zeamais. Hexane extracts and powders made from ripe and unripe banana and plantain peels were found to have insecticidal effect on C. maculatus in stored cowpea and S. zeamais in stored maize. At the highest concentration of application (10ml/kg) each hexane peel extract always caused significant mortality of both C. maculatus and S. zeamais adults in comparison with the control. Significantly reduced oviposition by C. maculatus and F1 adult emergence in C. maculatus and S. zeamais was also observed in treatments involving the highest concentration of each hexane peel extract. The insecticidal effect of hexane extract from unripe peels was generally greater than extracts from ripe peels. Except for powder obtained from ripe plantain peel, all the other peel powders exercised significant kill of C. maculatus adult in comparison with the control at 0.8g or more per 20g of grain and as from 12hours post treatment. All peel powders at all rates of application generally produced significant kill of S. zeamais adults as from 24hours post treatment. All peel powders at all rates of application significantly reduced oviposition by C. maculatus in comparison with the control treatment. The insecticidal effect of unripe peel powders was generally higher than ripe peel powders. The plantain and banana peel powders and hexane extracts were generally more toxic to adult of C. maculatus than S. zeamais adults.