Khan Imran, Zaman Shah, Li Guihua, Fu Mei
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China.
College of Bioscience and Biotechnology, Yangzhou University, Jiangsu, Yangzhou, China.
Front Plant Sci. 2025 Mar 28;16:1550125. doi: 10.3389/fpls.2025.1550125. eCollection 2025.
Plants depend on solar energy for growth via oxygenic photosynthesis. However, when light levels exceed the optimal range for photosynthesis, it causes abiotic stress and harms plant physiology. In response to excessive light, plants activate a series of signaling pathways starting from the chloroplast and affecting the entire plant, leading to stress-specific physiological changes. These signals prompt various physiological and biochemical adjustments aimed at counteracting the negative impacts of high light intensity, including photodamage and photoinhibition. Mechanisms to protect against light stress involve scavenging of chloroplastic reactive oxygen species (ROS), adjustments in chloroplast and stomatal positioning, and increased anthocyanin production to safeguard the photosynthetic machinery. Given that this machinery is a primary target for stress-induced damage, plants have evolved acclimation strategies like dissipating thermal energy via non-photochemical quenching (NPQ), repairing Photosystem II (PSII), and regulating the transcription of photosynthetic proteins. Fluctuating light presents a less severe but consistent stress, which has not been extensively studied. Nevertheless, current research indicates that state transitions and cyclic electron flow play crucial roles in helping plants adapt to varying light conditions. This review encapsulates the latest understanding of plant physiological and biochemical responses to both high light and low light stress.
植物通过有氧光合作用依靠太阳能生长。然而，当光照强度超过光合作用的最佳范围时，会导致非生物胁迫并损害植物生理机能。作为对过量光照的响应，植物会激活一系列从叶绿体开始并影响整个植株的信号通路，从而引发特定于胁迫的生理变化。这些信号促使植物进行各种生理和生化调节，旨在抵消高光强度带来的负面影响，包括光损伤和光抑制。抵御光胁迫的机制包括清除叶绿体中的活性氧（ROS）、调整叶绿体和气孔的位置，以及增加花青素的生成以保护光合机构。鉴于该光合机构是胁迫诱导损伤的主要靶点，植物已经进化出适应策略，如通过非光化学猝灭（NPQ）耗散热能、修复光系统II（PSII）以及调节光合蛋白的转录。波动光呈现出一种不太严重但持续存在的胁迫，对此尚未进行广泛研究。然而，目前的研究表明，状态转换和循环电子流在帮助植物适应变化的光照条件方面起着关键作用。本综述总结了对植物对高光和低光胁迫的生理生化响应的最新认识。
