Eradication of Cowpea Weevil (Coleoptera: Bruchidae)in Cowpeas by Solar Heating

Abstract

Exposing cowpeas (Vigma unguiculata) to temperatures > 57.3 degree C in an oven for 1 h killed cowpea weevil (Callosbruchus maculatus) larvae and pupae living within the seeds, and cowpea weevil adults living among the seeds. Using only the sun's rays and a simple heater constructed from cheap, widely available material, we demonstrated the feasibility of using solar energy to eliminate cowpea weevil from cowpea stores. The temperatures and exposure times necessary to disinfect cowpeas had no significant effect on the cooking time and percentage germination of cowpea seeds. Solar disinfection of cowpea stores using simple technology represents a new approach to preserving cowpeas from weevil attack, which may be useful at the level of subsistence farms in developing nations.