Beneficial effects of abscisic acid and melatonin in overcoming drought stress in cotton (Gossypium hirsutum L.)
Beneficial effects of abscisic acid and melatonin in overcoming drought stress in cotton (Gossypium hirsutum L.)
复制标题
脱落酸和褪黑激素对克服棉花干旱胁迫的有益作用（Gossypium hirsutum L.）
DOI：
10.1111/ppl.13550
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发表时间：
2021-09-18
影响因子：
6.4
通讯作者：
Yu, Runxing
中科院分区：
文献类型：
--
作者：
Hu, Wei;Zhang, Jipeng;Yu, Runxing
采用盆栽试验研究了脱落酸（阿坝）和褪黑激素（MT）对棉花抗旱性的影响及其联合作用。喷施阿坝或MT可改善干旱胁迫下叶片的水分状况和抗氧化能力，有利于光合活性的提高，最终提高皮棉产量。但阿坝和MT对干旱的缓解机制并不完全相同，主要表现为：（1）阿坝通过增加干旱胁迫下叶片的相对含水量，减少水分损失，而MT通过增加叶片相对含水量，提高水分吸收效率;（2）在酶促抗氧化系统中，阿坝和MT可能通过调节不同种类的超氧化物歧化酶来催化干旱条件下O-2（-）的还原;（3）在抗坏血酸（阿萨）-谷胱甘肽（GSH）循环中，MT可提高干旱胁迫下叶片中谷胱甘肽还原酶的活性，而阿坝则无此作用。干旱条件下，阿坝+ MT处理的叶片相对含水量和总抗氧化能力高于单一激素处理，导致H2 O2水平降低。对于酶抗氧化系统，单一激素处理影响Cu/ZnSOD或MnSOD的表达，但阿坝+ MT上调干旱胁迫叶片中的两个基因。激素配合施用也比单一激素处理有更高的CAT表达。在AsA-GSH循环中，阿坝+ MT处理的脱氢抗坏血酸还原酶活性高于单一激素处理，导致阿萨含量增加。此外，激素联合施用比单一激素引起更高的抗坏血酸过氧化物酶活性，表明它们的组合协同提高了阿萨清除ROS的能力。这些都证实了阿坝和MT在提高作物抗旱性方面具有协同效应。
Pot experiments were performed to study the effects of abscisic acid (ABA) and melatonin (MT) on cotton drought tolerance and to explore their combined effects. ABA or MT spraying promoted water status and antioxidant capacity of drought-stressed leaves, which was conducive to scavenge ROS, finally increasing lint yield. However, the mitigation mechanisms of ABA and MT on drought were not identical, which were mainly manifested as: (1) ABA increased the relative water content (RWC) of drought-stressed leaves via, reducing water loss, but MT increased it via, promoting water uptake efficiency; (2) for enzymatic antioxidant system, ABA and MT might modulate different kinds of superoxide dismutase to catalyze the reduction of O-2(-) under drought; and (3) for ascorbic acid (AsA)-glutathione (GSH) cycle, MT increased the glutathione reductase activity in drought-stressed leaves, but ABA did not. ABA + MT spraying led to higher leaf RWC and total antioxidant capacity than single hormone under drought, leading to a lower H2O2 level. For the enzymatic antioxidant system, single hormone treatment affected Cu/ZnSOD or MnSOD expression, but ABA + MT upregulated both genes in drought-stressed leaves. Hormones combined application also had higher CAT expression than single hormone. For AsA-GSH cycle, ABA + MT had higher dehydroascorbic acid reductase activity than single hormone, resulting in higher AsA content. Moreover, hormones combined application caused higher ascorbate peroxidase activity than single hormone, suggesting that their combination synergistically improved the ability of AsA to eliminate ROS. All these confirmed that ABA plus MT had synergistic effects on improving crop drought resistance.