Effect of temperature on reproduction and diapause of adults in the cabbage beetle, Colaphellus bowringi
Author of the article:
Author's Workplace:
Key Words:Colaphellus bowringi, temperature, egg production, egg hatching, longevity, diapause
Abstract: The cabbage beetle, Colaphellus bowringi Baly is a serious pest of crucifers. There are two distinct infestations in the field, one in spring and another in autumn. The beetle aestivates and hibernates as an adult in the soil. The effect of temperature on reproduction and diapause of adults in C. bowringi was systematically investigated at 20℃, 25℃ and 28℃ under L∶D=16∶8. The results show that mean daily egg production was highest at 28℃ (51.24±2.90) eggs, significantly higher than at 25℃ (39.57±2.86) eggs and 20℃ (31.53 ±2.02) eggs. However, there was no significant difference in the total number of eggs per female between these three temperatures due to the shortening of egg production with increasing temperature. The hatching rate of eggs at 28℃ was lower than at 20℃ and 25℃, but not significantly so. The lifespan of adults shortened with increasing temperature. The longevity of females was only significantly different between 20℃ and 28℃, whereas there were significant differences in the longevity of males at all three temperatures. About 30% adults entered diapause after they experienced a period of egg production. The duration of egg production for diapausing females gradually shortened with increasing temperature, and the total number of eggs produced also declined with temperature.