亚洲玉米螟两个不同地理种群对暗期干扰的滞育反应

为了探明亚洲玉米螟Ostrinia furnacalis (Guenée)不同地理种群对暗期干扰的滞育反应， 本文在研究了亚洲玉米螟南昌种群（28°41′N， 115°53′E）和哈尔滨种群（44°56′N， 127°10′E）光周期反应的基础上， 在室内分别测试了25℃和28℃温度下1 h的光脉冲干扰光周期L9∶D15和L12∶D12对这两个不同地理种群幼虫滞育抑制的影响。结果表明： 在25℃和28℃下， 哈尔滨种群的临界日长分别比南昌种群延长了1 h 40 min和2 h； 在所有测试的暗期干扰实验中， 除了极少数光脉冲干扰点外， 南昌种群幼虫滞育的发生率显著低于哈尔滨种群； 1 h光脉冲干扰光周期L9∶D15的滞育发生率明显低于干扰光周期L12∶D12， 且前者表现了暗期的中间对光脉冲最敏感， 而后者显示了暗期的初期对光脉冲最敏感； 28℃下光脉冲对滞育的抑制效果强于25℃。这些结果进一步提示， 即使在同种昆虫中， 如果地理种群和实验条件不同， 暗期干扰对滞育抑制的效果也可能不同。

Diapause response to night-interruption in two different geographic populations of the Asian corn borer,Ostrinia furnacalis (Guenée) Lepidoptera: Pyralidae)

In order to understand the effects of night-interruption on diapause-averting by different geographic populations of the Asian corn borer, Ostrinia furnacalis (Guenée), the photoperiodic responses and effects of night-interruption experiments on diapause-averting in two populations of O. furnacalis from Nanchang (28°41′N， 115°53′E) and Harbin (44°56′N， 127°10′E) were investigated in the laboratory, in which the scotophases of L9∶D15 and L12∶D12 were interrupted by 1 h light pulse at 25 and 28℃, respectively. The results showed that the critical day lengths in Harbin population at 25 and 28℃ were 1 h 40 min and 2 h longer than those in Nanchang population, respectively. In all night-interruption experiments, the incidences of diapause in almost all positions of light pulse in Nanchang population were significantly lower than that in Harbin population. When the light pulse was used to interrupt L9∶D15 and L12∶D12, the incidence of diapause was lower at L9∶D15 than that at L12∶D12. Furthermore, the most highly photo-sensitive position occurred in the middle of scotophase at L9∶D15, whereas the most highly photo sensitive position occurred in the early scotophase at L12∶D12. The effect of the light pulse on diapause-averting at 28℃ was greater than that at 25℃. These results further suggest that effect of night-interruption on diapause-averting may be different even in the same species depending on different geographic populations and the experimental conditions.