Assessment of Entomocidal Effects of Solar Radiation for the Management of Cowpea Seed Beetle Callosobruchus Maculatus F. Coleoptera Chrysomelidae in Stored Cowpea
Cowpea seed beetle, Callosobruchus maculatus (F.) is a major pest of cowpea, Vigna unguiculata (L.) Walp. in the tropics and subtropics. It causes remarkable quantitative and qualitative losses to stored cowpea in these regions. Therefore, an experiment to investigate the entomocidal effects of solar radiation for the management of C. maculatus was conducted in the laboratory of the Department of Crop, Soil and Pest Management, Federal University of Technology Akure. Twenty seeds of Oloyin cowpea were infested with freshly emerged adults of C. maculatus in Petri dishes replicated three times. Petri dishes and their contents were exposed to solar radiation for 1, 2 and 3 hours and subsequently removed from sun. They were left in the laboratory for the adult emergence. The results indicated that the different biological parameters studied were significantly (p<0.05) affected when the insects were exposed to solar radiations. The exposure to solar radiation significantly caused mortality, inhibits egg laying, embryonic development of C. maculatus resulting in inhibition of the emergence of the offspring. Thus, solar radiation could be an effective method for post-harvest management of cowpea seed beetle, C. maculatus to prevent damage during cowpea storage.