光温条件明显影响棉铃虫的滞育强度

为了探明不同地理种群棉铃虫Helicoverpa armigera滞育强度的地理变异, 本研究系统地比较了光温条件（光照时数 11～16 h, 恒温20, 22, 25, 28和31℃及变温）对来自中国的4个地理种群（广东广州、 江西永修、 山东泰安和辽宁喀佐）棉铃虫滞育强度的影响。结果表明： 滞育诱导的光周期对继后棉铃虫的滞育强度有明显影响。在光照时数11～14 h范围内, 各地理种群的滞育持续期均随着光照时数的增加而延长。滞育强度也受到滞育诱导的温周期影响, 当光期温度相同时, 低纬度的GZ种群温周期比恒温有更强的诱导效应; 中纬度的YX种群温周期与恒温具有相同的滞育诱导强度; 高纬度的KZ和TA种群温周期所诱导的滞育强度一般低于恒温。滞育解除过程中的温度也显著影响到滞育的解除, 在20~31℃下, 温度愈高滞育解除愈快; 滞育持续期同时受到滞育诱导温度的影响, 对于北方的泰安种群和喀佐种群, 较高的滞育诱导温度能诱导更强的滞育。

Photoperiod and temperature influence significantly diapause intensity of the cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae)

 To understand the geographic adaptation and geographic variation of diapause intensity in different geographic populations of the cotton bollworm, Helicoverpa armigera, the effects of photoperiod and temperature (daylengths of 11-16 h, constant temperatures of 20, 22, 25, 28 and 31℃, and thermoperiod) on diapause intensity of H. armigera from 4 different geographic populations (Guangzhou population, Yongxiu population, Tai’an population, and Kazuo population) were investigated. The results indicated that the photoperiods for diapause induction ranged from 11 to 14 h, and the daylength had a significant influence on diapause intensity. The duration of diapause in the four different geographic populations gradually prolonged with the daylength increasing. The diapause intensity was also affected by the thermoperiod for diapause induction. When the photophase temperature was the same, Guangzhuo population from low latitude showed longer diapause duration at thermoperiod than at constant temperature; there were no significant differences in the duration of diapause between the thermoperiod and constant temperature in Yongxiu population from mid-latitude; on the contrary, the diapause duration induced at thermoperiod temperature was shorter than that at constant temperature in northern Kazuo and Tai’an populations. Temperature during diapause significantly affected diapause duration, at 20-31℃, and the duration of diapause was significantly shortened with the temperature increasing. However, the duration of diapause was also affected by the temperature for diapause induction. Higher constant temperature induced a stronger diapause in northern Kazuo and Tai’an populations.