作物对干旱胁迫的响应机制及提高作物抗旱能力的调控措施研究进展

干旱是影响作物生长发育和产量的最主要非生物胁迫之一,在气候变化背景下,作物遭受干旱胁迫的风险越来越大。为了应对干旱,作物表现出一系列的抵御机制,包括形态特征和生理生化（抗氧化酶、渗透调节物质、内源激素）特性改变。本研究从上述2个方面总结了作物对干旱胁迫的响应机制,并对提高作物抗旱能力的调控措施进行了论述,主要包括：（1）筛选抗旱性品种,促进对深层土壤贮水的吸收利用;（2）地面覆盖,有利于降低土壤蒸发,增加土壤含水量;（3）节水灌溉技术,如微喷灌、滴灌等灌溉方式能实现少量多次灌溉,根区局部灌溉有利于调节气孔关闭,减少奢侈蒸腾,降低土壤蒸发;（4）抗蒸腾剂,在作物枝干及叶面表层形成超薄透光的保护膜,抑制作物水分过度蒸腾;（5）植物生长调节剂,调控植物生理代谢,增强抗旱性;（6）纳米肥料,改变作物生理生化反应,促进植株生长发育;（7）生物炭,有利于土壤通气保水,改善土壤的物理性质和土壤的持水能力。本研究系统地对以上7种措施提高作物抗旱能力的作用机理、应用前景及存在问题进行了论述,以期为应对干旱胁迫提供理论依据和技术参考。

Response Mechanism of Crops to Drought Stress and Measures for Improving Drought Resistance of Crops: Research Progress

Drought is one of the most important abiotic stresses affecting the growth and yield of crops. The risk of crops suffering from drought stress is increasing under climate change. In order to cope with drought, crops show a series of resistance mechanisms, including the changes of morphological characteristics, and physiological and biochemical characteristics (antioxidant enzyme, osmotic regulation substances, and endogenous hormone), which play an important role in improving the resistance of crops under drought conditions. This paper summarized the response mechanism of crops to drought stress and introduced the measures to improve the drought resistance ability of crops, including: (1) selecting drought-resistance cultivars to promote the absorption of deep soil water; (2) soil mulching, which could reduce soil evaporation and increase soil water content; (3) water-saving irrigation techniques, such as micro-sprinkler irrigation and drip irrigation, which could precisely control the irrigation application and increase irrigation frequency; in addition, partial root-zone irrigation could reduce luxurious transpiration and soil evaporation by regulating stomatal closure; (4) anti-transpirants, which could inhibit excessive transpiration of water by forming ultrathin transparent protective film on the surface of crop branches and leaves; (5) plant growth regulators, which could enhance crop drought resistance by regulating plant physiological metabolism; (6) nano-fertilizers, which could promote plant growth and development by changing physiological and biochemical reactions of crops and enhance drought resistance of crops; (7) biochar, which is beneficial to soil aeration and water retention, and could improve soil physical properties and soil water retention capacity. In order to provide a theoretical basis and technical reference for coping with drought stress, this paper systematically discussed the action mechanism, application prospect and existing problems of the above 7 measures.