© Science and Education Publishing DOI:10.12691/ajzr-2-2-3 Studies on the Resistance of Cowpea Seeds (Vigna unguiculata) to Weevil (Callosobruchus maculatus)

Abstract Three cowpea varieties namely: Kafanji, Brown variety and Ex-potiskum were used in this study to test their resistance on weevil infestation. Cowpea samples of 60grams were measured from each variety and were artificially infested with different weevil densities made up of male and female ratios of 5:10, 10:15 and 15:15. The samples had three replicates and a control treatment each. These were allowed to stand on the shelves without disturbance, thus making it possible for the weevils to mate and oviposit naturally. The results were analysed statistically and the differences between the treatments with respect to weight loss and adult emergence were significant (P>0.05) and the damages were also closely related to the infestation density increasing with the densities. Kafanji suffered more damage while the Brown variety and Ex-potiskum suffered less damage. This indicates that Ex-potiskum and Brown-variety exhibits more resistance qualities to the weevil attack than Kafanji which is more susceptible to the weevil attack. The physical as well as the chemical characteristics of the seeds were also found to influence the growth and development of the weevil forming the basis for resistance in the varieties. Breeding programmes utilizing the resistance characters in certain varieties are therefore suggested