Abstract
The southern cowpea weevil Callosobruchus maculatus (F) Bruchidae. Coleoptera. is regarded as an important pest on pulses or grain legumes in different parts of the world. The results obtained from current studies indicate that the average number of eggs laid by females decreases significantly as the age increases. The highest average was in the first days of their lives. subsequently the average decreased as they became older. It has been found that the average number of eggs laid by one female is 73.43 egg at 27±3ºC.& 70±10%R.H. It has been observed that the larvae which hatched on kidney beans failed to develop and all died within a short period after hatching. The highest average of adults that emerged. were of those larvae which reared on cowpea while the lowest average were of those reared on grind chick-pea. The feeding of weevil larvae on different pulses has a significant effect on their biology and their development period. The shortest period was on green gram and longest period on lentil seeds. It has been observed that the different diet of larvae has an impact on the longevities of adults that emerged from them. The longest period of adults was 8.5 for males and 9.3 days for females that emerged from larvae which fed on green gram. In comparison this period shortened to 5.3 days for females and 4.3 days for males that emerged from larvae which fed on lentil seed. In all cases the longevities of females were longer than males. Finally it has been found that C. maculatus have six generation under laboratory conditions.
