Combination Effect of Maternal Age and Temperature on the Rate of Increase of the Cowpea Weevil, Callosobruchus maculatus (F.)

Document Type : Original Article


1 Department of Biological Sciences, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah, 21589, Saudi Arabia

2 Plant Protection Department, College of Food and Agricultural Sciences, King Saud University, P. O. Box 2469, Riyadh 11451, Saudi Arabia

3 Department of Biological Sciences, Faculty of Science, University of Tubak, P. O. Box 741,Tabuk, Saudi Arabia


The cowpea weevil, Callosobruchus maculatus (Coleoptera: Chrysomelidae), is the most serious insect pest attacking stored pulses in tropical and subtropical regions.  The effects of maternal age on offspring fitness of the cowpea weevil have been previously studied, but the combined effects of maternal age and temperature are reported here for the first time.  Adult longevity was negatively correlated with temperature, and female longevity was longer than males.  The number of eggs deposited daily was negatively correlated with maternal age for the tested temperatures.  Females required 24 hours longer at 20oC and 25oC and 12 hours longer at 30oC than males to develop from egg to the adult stage.  The mean intrinsic rates of increase were 0.06, 0.10, and 0.15 at 20, 25, and 30oC, respectively.  There was a significant positive correlation between maternal age and development time at 25oC.  Percent survival was negatively correlated with the maternal age at 20 and 30oC.  The effects of maternal age were not consistent at the three tested temperatures; therefore, there is a need for additional studies of the impact of maternal age on offspring quality under different biotic and abiotic conditions.