n African Entomology - Temperature effects on development and survival of the sweetpotato weevil, Cylas puncticollis Boheman (Coleoptera : Apionidae)
|Article Title||Temperature effects on development and survival of the sweetpotato weevil, Cylas puncticollis Boheman (Coleoptera : Apionidae)|
|© Publisher:||Entomological Society of South Africa (ESSA)|
|Author||L. Nteletsana, A.S. Schoeman and M.A. McGeoch|
|Publication Date||Mar 2001|
|Pages||49 - 57|
|Keyword(s)||Cylas species, Degree-days, Development, Ipomoea batatas and Temperature thresholds|
The effects of temperature on the development and survival of the sweetpotato weevil, Cylas puncticollis were studied in the laboratory at six constant temperatures (16.03, 18.60, 24.11, 26.38, 31.23 and 35.82 °C). The photoperiod was maintained at 12L : 12D for all temperatures, but RH was not controlled. Thermal requirements (r and k) of this pest species were estimated for all the immature stages and for the total life-cycle. Duration of development from hatching to pupation was observed for individuals disturbed at regular intervals to determine instar-specific development rate. This was compared with total development duration for sets of individuals not disturbed in this way. As expected, development rate was slower at lower temperatures. At 16.03 °C there was no development beyond the first larval instar. The larval period was longer than other stages at all temperatures. A significant difference in total development rate of adults was observed between the two treatments (disturbed and undisturbed), except at 18.60 °C. Mortalities were highest at 16.03, 18.60 and 35.82 °C. Temperature had no effect on the sex ratio of C. puncticollis.
Article metrics loading...