EFFICACY OF MICROWAVE ENERGY ON: 1- COWPEA WEEVIL, Callosobruchus maculatus (F), SOME OF CHEMICAL CONTENTS AND VIABILITY FOR FABA BEAN SEEDS

Abstract

This study conducted to evaluate the efficacy of microwave energy on all stages of cowpea weevil, Callosobruchus maculatus (F.) reared on faba bean seeds exposed to microwave at the lowest energy (17% of 800W.) for the 2,3,4,5, and 6 minutes. Exposure of adults to microwave energy for 5 minutes caused 90% mortality and complete reduction of progeny. When the eggs laid on faba bean seeds were exposed to microwave energy for 5 minutes, the hatchability was 1.9% compared with control (77.7 %). When the larvae inside the seeds were exposed to microwave energy for 5 minutes, complete reduction of progeny was found. Microwave did not affect on pupa stage at all periods of exposure. There was no significant difference in the chemical composition, crude protein, oil and total carbohydrate contents between treated and untreated faba bean seeds to microwave energy. Meantime, results of SDS-PAGE in soluble seed protein revealed a total number of 22 bands (6 common bands were monomorphic while the other were polymorphic). The maximum number of bands ( 14) appeared with 5 minutes of exposure time but when exposure time decreased to 3 and 4 minutes, it showed the minimum number of bands (10). There was no significant differences in viability and seedling vigor traits of untreated or treated faba bean seeds with microwave energy for 2,3,4, and 5 minutes. Highly significant reduction in the viability and seedling vigor were recorded with exposure time of 6 minutes. Highly significant loss of 100-seed weight was recorded after treatment with microwave energy for 6 minutes compared with other treated and untreated seeds.