The biology of the sweet potato weevil. Cylas puncticollis Boheman (Colleoptera: Apionidae) in southwestern Nigeria
ANOTA. T. and ODEBIYI. J.A.
ABSTRACT: Studies on the biology of C. puncticollis BOH. were carried out under laboratory conditions at 25- 30°C and 70 percent RH. The average incubation period was 3.3 days. There were three larval instars. The duration of larval and pupal stages were 11.4 and 6.2 days respectively. The total development period from egg to adult averaged 20.9 days. The fecundity of
mated females ranged from 201 to 496 eggs, with a preoviposition period of 3-4 days (mean 3.6) and an oviposition period of 41-91 days (mean 67.2). The total life span of mated females varied from 44 to 95 days (mean 74.3) while that of mated males ranged from 46 to 69 days (avg, 54.8). An increase in the proportion of females beyond a ratio of 1 male: 1 female and that of males beyond a ratio of 2 males : 1 female had a depressing effect on fecundity.