Investigation of Cowpea Variety and Storage Methods on Cowpea Beettle Infestation

Investigation of effect of cowpea variety and storage methods on cowpea beetle (callosobuchus maculates) control was carried out with the main aim of providing suitable, safe and affordable methods of storing various varieties of cowpea devoid of infestation. Three varieties of cowpea which are White, Brown and Black varieties were used for this research. Various storage methods which include Plastics, Polyethylene, Hessian bags and Aluminum Bins of 10 kg capacity each was used in storing the cowpea. Twenty (20) cowpea beetle were introduced into the stored cowpea. Storage chemicals (phostoxine and Atelic dust) were introduced into the various stored cowpea at the same time of introducing the cowpea beetle. For each treatment there was a control and each was replicated three times. The storage was observed for a period of 90 days. The data generated were analyzed using MINITAB statistical software in analysis of variance (ANOVA).The result showed thatthe control treatment was generally less effective than the phostoxine and atelic dust at 90 days of storage and infestation of the cowpea. From tables 1, 2 and 3 all the storage methods were effective against the insect with significantly varying degree of efficiencies. Cowpea beetle mortality was significantly affected on the white variety more especially on the polyethylene storage and plastic containers with 95% and 100% mortality respectively. The Atelic showed mortality rate of 85 % for both polyethylene and plastic containers while the control treatment has a value of 65 % and 70 % for both the polyethylene and plastic containers respectively. The Aluminum bin showed 80% mortality on phostoxine combination, 75% for the atelic and 50 % for the control treatment.The mortality on the Black variety was significantly high after the 90 days infestation and storage for all the treatments and storage methods except for the Hessian bags that indicated 65 % for phostoxine, 60 % for atelic and 0 % for the control treatment. The black variety showed less susceptibility to cowpea infestation when stored in polyethylene bag and airtight plastic container which had 100 % mortality each.