Effectiveness of Oils in Protecting Stored Cowpeas from the Cowpea Weevil (Coleoptera: Bruchidae)
Journal of Economic Entomology
Applications of five chemically differing oils (three vegetable oils, mineral oil, and polyethylene glycol) at dosages of 5.0 ml of oil per kg of seed effectively protected cowpeas, Vigna unguiculata, from Callosobruchus maculates (F.). Oils caused high mortality of eggs and larvae on the seed surface, but had no effect on individuals that successfully entered the seed. A lack of oil-specific activity indicated that the protective property was physical rather than chemical. After 30 days in storage, treated seeds were more deterrent to ovipositing females than were newly treated seeds, but the stored seeds were less toxic to eggs and larvae. Oil application may therefore be useful for only a limited period of time.
Messina, F.J. & J.A.A. Renwick. 1983. Effectiveness of oils in protecting stored cowpeas from the cowpea weevil (Coleoptera: Bruchidae). Journal of Economic Entomology 76: 634-636.