Survey and control of sweet potato insect pests with special emphasis on sweet potato weevils, Cylas spp

Abstract

Thirty-eight sweet potato cloves were tested for resistance Tocylas spp during the long rains of 1990. The crown, stem base and tubers were scored for weevil damage. The larvae and grubs in the tubers and adults around the hills were counted. Sweepnet and sunction trap were used, to collect other insect pests on the crop. Lagria villosa F., Gonocephalum simplex F, Systates pollinosus Gerst, Paederus sabacus ER, Formicomis tuberculifer pic, Cheilomenes lunette F, Alcidodes clathratus Bert, Pontiahelica F, and Macrosiphum euphorbiae Thomas were the insect pests collected in the sweet potato crop. Except for sporadic build up, pests were in very low numbers. There were no significant differences in weevil infestation between varieties. However Kemp 7 had lower scores for external and internal damage compared with the other varieties.