Reproductive Properties of Sweet Potato Weevil, Cylas formicarius (Fabricius) (Coleoptera, Brentidae)

Abstract

Sweet potato weevil (SPW), Cylas formicarius is a serious pest of sweet potato causing extensive damage to tubers. The present study investigates the reproductive properties of sweet potato weevil in laboratory conditions. Current investigation revealed that sexual maturity of SPW was attained on 5th Days After Emergence (DAE) as in the case of male weevils and 100% males were found to attain sexually maturity within 20-25 DAE but in the case of female these were 4 and 10 DAE, respectively. Effect of crowding on fecundity and longevity of SPW revealed that the average fecundity of female SPW was 198.90 when both sexes were exposed together until the death of male; whereas the average fecundity of 6.65±2.21 was observed when they were exposed just for 24 hours; and 79.20±9.35 when exposed for one week. It was also noticed that the highest progeny production and longevity were found in SPW with the combination of 1:1 male to female. An increase in the population of males in the colony resulted in significant reduction in the longevity of female weevils.