Sakamoto Tomoaki, Tomioka Kenji
Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan.
Zoolog Sci. 2007 Jun;24(6):604-10. doi: 10.2108/zsj.24.604.
The cricket, Modicogryllus siamensis, shows clear photoperiodic responses at 25 degrees C in nymphal development. Under long-day conditions (LD16:8), nymphs became adults about 50 days after hatching, while under short-day conditions (LD8:16) the duration of nymphal stage extended to more than 130 days. Under constant dark conditions, two developmental patterns were observed: about 60% of crickets became adults slightly slower than under the long-day conditions, and the rest at later than 100 days after hatching, like those under the short-day conditions. When the compound eye was unilaterally removed on the 2nd day of hatching, an increase of molting and an extension of the nymphal period were observed under the long-day conditions, while under the short-day conditions, some crickets developed faster and others slower than intact crickets. These results suggest that this cricket receives photoperiodic information through the compound eye, that a pair of the compound eyes is required for a complete photoperiodic response, and that interaction between bilateral circadian clocks may be also involved in the response.
暹罗凹颚蟋在若虫发育阶段，于25摄氏度时表现出明显的光周期反应。在长日照条件（LD16:8）下，若虫孵化后约50天变为成虫，而在短日照条件（LD8:16）下，若虫期延长至130多天。在持续黑暗条件下，观察到两种发育模式：约60%的蟋蟀变为成虫的速度略慢于长日照条件下，其余的在孵化后100天之后变为成虫，类似于短日照条件下的情况。在孵化后第2天单侧摘除复眼，在长日照条件下观察到蜕皮增加和若虫期延长，而在短日照条件下，一些蟋蟀发育得比完整蟋蟀快，另一些则慢。这些结果表明，这种蟋蟀通过复眼接收光周期信息，完整的光周期反应需要一对复眼，并且双侧生物钟之间的相互作用可能也参与了该反应。
