植物主要光周期成花调控途径及其纬度适应性的研究进展

Research Progress on Major Photoperiod Flowering-regulation Pathways in Plants and Their Latitudinal Adaptation

摘要:

光周期是植物能够感知到的最稳定、最可靠的环境信号，在植物开花时间及其生命周期的调控中具有核心作用。不同植物在进化过程中建立了以CO-FT模块为核心的光周期调控网络，并在此基础上演化出多样化的、适应不同生态环境的特异性路径。由于地球自转轴倾斜带来的太阳辐射节律，地理纬度决定了特定地区日照时长的年际稳定性，即每年同一时段的光周期相对固定，因此纬度决定了植物所经历的光周期环境；而植物对光周期变化的响应也常被用作反映纬度适应性的生物指标。开花作为植物对光周期变化最敏感的表型之一，成为研究植物纬度适应性的重要切入点。当前的研究主要集中于拟南芥(Arabidopsis thaliana)、大豆(Glycine max)和水稻(Oryza sativa)等典型长日照与短日照植物的光周期途径的开花调控机制。该文将以这3种植物的光周期途径及其纬度适应性为主展开综述：拟南芥形成了以CO (constans)正调控FT (flowering locus T)的经典长日照促花模型；大豆演化出以E1为核心、抑制FT表达的短日照调控机制，并在不同纬度形成多样化适应策略；水稻则同时保留了保守的OsGI-Hd1-Hd3a途径和特有的Ghd7-Ehd1-Hd3a/RFT1途径，增强了对光周期环境的适应性。通过对比分析，展示了主要的植物光周期成花调控途径的保守性、多样性和纬度适应性，为该途径的深入研究和作物育种提供参考。

Abstract:

Photoperiod is the most stable and reliable environmental signal perceived by plants, playing a core role in regulating flowering time and life cycle. During evolution, diverse plant species have established photoperiodic regulatory networks centered on the CO-FT module, which have further diversified into lineage-specific pathways adapted to different ecological environments. Due to the solar radiation rhythm caused by the tilt of the Earth’s axis of rotation, geographical latitude determines the interannual stability of day length in a given region, that is, the photoperiod remains relatively constant at the same time each year. Therefore, latitude defines the photoperiodic environment experienced by plants. Conversely, plant responses to changes in photoperiod are often used as biological indicators of latitude adaptation. Flowering, as one of the most sensitive phenotypes to photoperiod changes, has become an important entry point for studying the latitudinal adaptability of plants. Current research mainly focuses on the flowering regulation mechanisms of the photo-period pathways in typical long-day and short-day plants such as Arabidopsis thaliana, Glycine max, and Oryza sativa. This article will mainly review the photoperiod pathways and latitudinal adaptability of these three plants: Arabidopsis thaliana has formed a classic long-day flowering promotion model centered on the positive regulation of FT (flowering locus T) by CO (constans); Glycine max has evolved a short-day regulatory mechanism centered on E1 that inhibits the expression of FT and has developed diverse adaptation strategies at different latitudes; Oryza sativa retains both the conserved OsGI-Hd1-Hd3a pathway and the unique Ghd7-Ehd1-Hd3a/RFT1 pathway, enhancing its adaptability to photoperiod environments. Through comparative analysis, the conservation, diversity, and latitudinal adaptability of the main plant photoperiod flowering regulation pathways are demonstrated, providing a reference for in-depth research on this pathway and crop breeding.