Lv Changning, Ren Yibo, Krylov Viacheslav V, Wang Yumeng, Li Yuanyuan, Pan Weidong, Hu Gao, Chen Fajun, Wan Guijun
Sanya Research Institute, Nanjing Agricultural University, Sanya 572025, China.
State Key Laboratory of Agricultural and Forestry Biosecurity, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
Insects. 2025 Jul 9;16(7):705. doi: 10.3390/insects16070705.
The circadian clock orchestrates behavioral and molecular processes such as eclosion. Understanding eclosion timing may offer insights into circadian mechanisms underlying migratory timing. Here, we characterize the diel and circadian patterns of eclosion and core clock gene expression in the fall armyworm (FAW), , a globally distributed migratory moth. Using a custom-designed eclosion monitoring system under 14 h light: 10 h dark (L14: D10) and constant darkness (DD) conditions, we observed robust diel eclosion rhythms peaking shortly after lights-off under L14: D10, which became delayed and damped over three consecutive days in DD. Males showed a tendency toward more dispersed emergence patterns and exhibited statistically distinguishable eclosion distributions from females under both conditions. Expression of five canonical clock genes (, , , , ) displayed significant 24 h rhythmicity, with generally higher mesors in males. However, sex-specific differences in amplitude and phase were detected only for and under L14: D10, not in DD. These findings suggest that sex-specific differences in circadian regulation are limited. Nonetheless, subtle variations in clock gene output and emergence timing in the FAW population established in China may contribute to sex-specific ecological strategies in the novel migratory arena.
昼夜节律时钟协调诸如羽化等行为和分子过程。了解羽化时间可能有助于深入了解迁徙时间背后的昼夜节律机制。在此，我们描述了全球分布的迁徙蛾类草地贪夜蛾羽化及核心时钟基因表达的昼夜和昼夜节律模式。在14小时光照：10小时黑暗（L14:D10）和持续黑暗（DD）条件下，使用定制设计的羽化监测系统，我们观察到在L14:D10条件下，羽化呈现出强烈的昼夜节律，在熄灯后不久达到峰值，而在DD条件下，这种节律在连续三天中变得延迟且减弱。在两种条件下，雄性的羽化模式往往更分散，并且其羽化分布与雌性在统计学上有显著差异。五个经典时钟基因（、、、、）的表达呈现出显著的24小时节律性，雄性的中值通常更高。然而，仅在L14:D10条件下检测到和的振幅和相位存在性别特异性差异，在DD条件下未检测到。这些发现表明昼夜节律调节中的性别特异性差异是有限的。尽管如此，在中国建立的草地贪夜蛾种群中，时钟基因输出和羽化时间的细微变化可能有助于在新的迁徙环境中形成性别特异性的生态策略。
