植物激素对铝毒胁迫反应调控的研究进展

Research Advance in the Regulatory Mechanism of Phytohormone for Plant Responses to Aluminum Toxicity Stress

铝是地壳中含量最丰富的金属元素,土壤酸化会导致其中铝的溶解度大幅增加,产生大量对植物有毒害作用的离子态Al3+,抑制根系生长,对养分吸收及众多生理生化代谢过程都会产生影响,进而降低作物产量。铝毒胁迫已经成为占全球耕地面积40%酸性土壤中作物生长的最主要限制因子。植物激素是调控植物应对各种环境胁迫反应的关键内源因子,对植物提升抗逆性和应对胁迫适应性生长、生存至关重要。脱落酸、生长素、乙烯、细胞分裂素和茉莉酸等主要植物激素在调控植物应对铝毒胁迫反应过程中发挥重要作用。大量研究表明,植物激素还可以通过调控细胞壁修饰酶活性、活性氧代谢和有机酸分泌来提升植物对铝毒胁迫的适应性。此外,不同植物激素信号间也存在复杂的交互作用,共同介导和调控植物应对铝毒胁迫适应性反应。为全面了解植物激素在铝毒胁迫反应中的作用机制,为植物铝毒耐性分子遗传改良提供新的思路,对植物激素信号在参与植物响应铝毒胁迫反应过程中的信号转导和调控作用进行综述,并对铝毒胁迫下植物激素的研究方向进行展望。

Aluminum is the most abundant metal element in the crust. Soil acidification will cause great increase of the aluminum solubility to produce a large number of Al3+, which is toxic to plants. The activated aluminum will inhibit root growth, affect nutrient absorption and many physiological and biochemical metabolism processes, and further reduce crop yield. Aluminum toxicity has been the most important limiting factor for crop growth in acid soils which account for about 40% of cultivated land in the world. Phytohormones are the key endogenous factors that regulate plant responses to various environmental stresses, and are crucial to the improvement of plant resistance and plant survival under various stresses. It is well known that abscisic acid, auxin, ethylene, cytokinin, jasmonic acid and other major plant hormones play an important role in regulating plant responses to aluminum toxicity stress. A large number of studies have shown that plant hormones can also improve the adaptability of plants to aluminum stress by regulating the activities of cell wall-modifying enzymes,reactive oxygen species metabolism and organic acid secretion. In addition, there are complex interactions between different plant hormone signals, which jointly mediate and regulate the adaptive response of plants to aluminum stress. In order to have a more comprehensive and in-depth understanding of the mechanism of plant hormones in aluminum toxicity response,and to provide new ideas for molecular genetic improvement of plants tolerance to aluminum toxicity, in the study, the signal transduction and regulation of plant hormone signals in the process of plant response to aluminum toxicity stress are reviewed,and the future research direction of plant hormones under aluminum toxicity stress is prospected.