Furlan Ana, Bianucci Eliana, Del Carmen Tordable María, Kleinert Aleysia, Valentine Alexander, Castro Stella
Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36, Km. 601, 5800 Río Cuarto, Córdoba, Argentina.
Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
Funct Plant Biol. 2016 Apr;43(4):337-345. doi: 10.1071/FP15206.
Drought stress is one of the most important environmental factors that adversely affect the productivity and quality of crops. Most studies focus on elucidating plant responses to this stress but the reversibility of these effects is less known. The aim of this work was to evaluate whether drought-stressed peanut (Arachis hypogaea L.) plants were capable of recovering their metabolism upon rehydration, with a focus on their antioxidant system. Peanut plants in the flowering phase (30 days after sowing) were exposed to drought stress by withholding irrigation during 14 days and subsequent rehydration during 3 days. Under these conditions, physiological status indicators, reactive oxygen species production and antioxidant system activity were evaluated. Under drought stress, the stomatal conductance, photosynthetic quantum yield and 13C:12C ratio of the peanut plants were negatively affected, and also they accumulated reactive oxygen species. The antioxidant system of peanut plants showed increases in superoxide dismutase-, ascorbate peroxidase- and glutathione reductase-specific activities, as well as the total ascorbate content. All of these responses were reversed upon rehydration at 3 days. The efficient and dynamic regulation of variables related to photosynthesis and the antioxidant system during a drought and rehydration cycle in peanut plants was demonstrated. It is suggested that the activation of the antioxidant system could mediate the signalling of drought stress responses that enable the plant to survive and recover completely within 3 days of rehydration.
干旱胁迫是对作物生产力和品质产生不利影响的最重要环境因素之一。大多数研究集中于阐明植物对这种胁迫的反应，但这些影响的可逆性却鲜为人知。这项工作的目的是评估干旱胁迫下的花生（Arachis hypogaea L.）植株在复水后是否能够恢复其代谢，重点关注其抗氧化系统。处于开花期（播种后30天）的花生植株在14天内通过停止灌溉而遭受干旱胁迫，随后在3天内进行复水。在这些条件下，评估了生理状态指标、活性氧的产生和抗氧化系统活性。在干旱胁迫下，花生植株的气孔导度、光合量子产率和13C:12C比率受到负面影响，并且它们还积累了活性氧。花生植株的抗氧化系统表现出超氧化物歧化酶、抗坏血酸过氧化物酶和谷胱甘肽还原酶的比活性增加，以及抗坏血酸总含量增加。在3天复水后，所有这些反应都发生了逆转。证明了花生植株在干旱和复水周期中与光合作用和抗氧化系统相关变量的有效和动态调节。有人提出，抗氧化系统的激活可以介导干旱胁迫反应的信号传导，使植物能够在复水3天内完全存活并恢复。
