气候变化和紫外线(UV)辐射的不断升级的影响使植物受到UV-B和干旱胁迫的独特组合。这些组合的压力源可能有加性,协同,或拮抗作用,但是这些影响的确切性质仍然不确定,阻碍了我们预测植物对压力源适应方法的能力。我们对各种研究的分析表明,UV-B或干旱条件会通过增加活性氧的产生而对植物生长和健康指标产生不利影响,从而对脂质造成损害。蛋白质,碳水化合物和DNA。进一步减少生物量积累,植物高度,光合效率,叶面积,和水的蒸腾作用,同时增强与压力相关的症状。响应UV-B辐射和干旱胁迫,植物表现出明显的特定适应相关代谢物的上调,包括脯氨酸,黄酮类化合物,花青素,不饱和脂肪酸,和抗氧化剂。这些代谢物在保护免受环境压力方面起着关键作用。它们的生物合成和功能作用可能由信号分子如过氧化氢调节,脱落酸,茉莉酸,水杨酸,和乙烯,所有这些都有相关的遗传标记,进一步阐明它们参与应激反应途径。与单一压力相比,UV-B和干旱的结合会引起植物防御反应和生长迟缓,而这些反应和生长迟缓的累加性不足。这种次加性反应,在不同的学习环境中保持一致,表明了交叉抗性机制的可能性。我们的概述暗示,干旱和UV-B增加的不利影响可能会通过使用多维方法在UV-B和干旱制度之间进行串扰来减轻。面对持续的全球气候变化,这一至关重要的见解可以大大有助于提高我们对压力耐受性的理解。
The escalating impact of climate change and ultraviolet (UV) radiation is subjecting plants to unique combinations of UV-B and drought stress. These combined stressors could have additive, synergistic, or antagonistic effects, but the precise nature of these impacts remains uncertain, hampering our ability to predict plant adaptations approach towards stressors. Our analysis of various studies shows that UV-B or drought conditions detrimentally influence plant growth and health metrics by the enhanced generation of reactive oxygen species causing damage to lipids, proteins, carbohydrates and DNA. Further reducing biomass accumulation, plant height, photosynthetic efficiency, leaf area, and water transpiration, while enhancing stress-related symptoms. In response to UV-B radiation and drought stress, plants exhibit a notable up-regulation of specific acclimation-associated metabolites, including proline, flavonoids, anthocyanins, unsaturated fatty acids, and antioxidants. These metabolites play a pivotal role in conferring protection against environmental stresses. Their biosynthesis and functional roles are potentially modulated by signalling molecules such as hydrogen peroxide, abscisic acid, jasmonic acid, salicylic acid, and ethylene, all of which have associated genetic markers that further elucidate their involvement in stress response pathways. In comparison to single stress, the combination of UV-B and drought induces the plant defence responses and growth retardation which are less-than-additive. This sub-additive response, consistent across different study environments, suggests the possibility of a cross-resistance mechanism. Our outlines imply that the adverse effects of increased drought and UV-B could potentially be mitigated by cross-talk between UV-B and drought regimes utilizing a multidimensional approach. This crucial insight could contribute significantly to refining our understanding of stress tolerance in the face of ongoing global climate change.