Seeds of four Irradiated and non- irradiated cowpea varieties were evaluated
according to their susceptibility to infestation by Cal/osobruchus mac latus to
determine the relationship between seed variety and susceptibility level. n mber of
eggs laid, hatchability, failure of larv •• : instars to penetrate the seed testa, duration of
development, number of emerged adults and rate of survival, sex ratio. dead larvae
within the cotyledon and impact of infestation on weight loss. Obtained results indicated that Ihere were different changes in the biological
properties of this pest, among the Irradiated and non- irradiated four cowpea varieties.
The radiation doses causing remarkable increase in Internal mortality In all varieties.
The relativery resistant variety 8alady showed the highest level of mortality. Azmerly
and DOkki were less resistant while, Karem 7was moderately susceptible. However
non- irradiated Balady and Dokki varieties showed moderately susceptible, Azmerly
and Karem7 were susceptible. II could be concluded that the susceptible 0 cowpea
varieties was radiation dependent.