Ma Xiaohua, Zheng Jian, Zhang Xule, Hu Qingdi, Qian Renjuan
Institute of Subtropical Crops of Zhejiang ProvinceWenzhou, China.
Front Plant Sci. 2017 Apr 21;8:600. doi: 10.3389/fpls.2017.00600. eCollection 2017.
Salt stress critically affects the physiological processes and morphological structure of plants, resulting in reduced plant growth. Salicylic acid (SA) is an important signal molecule that mitigates the adverse effects of salt stress on plants. Large pink L. (Caryophyllaceae) usually exhibit salt-tolerant traits under natural conditions. To further clarify the salt-tolerance level of . and the regulating mechanism of exogenous SA on the growth of under different salt stresses, we conducted a pot experiment to examine the biomass, photosynthetic parameters, stomatal structure, chloroplast ultrastructure, reactive oxygen species (ROS) concentrations, and antioxidant activities of . young shoots under 0.3, 0.6, and 0.9% NaCl conditions, with and without 0.5 mM SA. exhibited reduced growth rate, decreased net photosynthetic rate (Pn), increased relative electric conductivity (REC) and malondialdehyde (MDA) contents, and poorly developed stomata and chloroplasts under 0.6 and 0.9% salt stress. However, exogenously SA effectively improved the growth, photosynthesis, antioxidant enzyme activity, and stoma and chloroplast development of . . However, when the plants were grown under severe salt stress (0.9% NaCl condition), there was no significant difference in the plant growth and physiological responses between SA-treated and non-SA-treated plants. Therefore, our research suggests that exogenous SA can effectively counteract the adverse effect of moderate salt stress on . growth and development.
盐胁迫严重影响植物的生理过程和形态结构，导致植物生长减缓。水杨酸（SA）是一种重要的信号分子，可减轻盐胁迫对植物的不利影响。大花剪秋罗（石竹科）在自然条件下通常表现出耐盐特性。为了进一步阐明大花剪秋罗的耐盐水平以及外源SA在不同盐胁迫下对其生长的调节机制，我们进行了盆栽试验，以研究在0.3%、0.6%和0.9% NaCl条件下，添加和不添加0.5 mM SA时大花剪秋罗嫩枝的生物量、光合参数、气孔结构、叶绿体超微结构、活性氧（ROS）浓度和抗氧化活性。在0.6%和0.9%盐胁迫下，大花剪秋罗生长速率降低，净光合速率（Pn）下降，相对电导率（REC）和丙二醛（MDA）含量增加，气孔和叶绿体发育不良。然而，外源SA有效改善了大花剪秋罗的生长、光合作用、抗氧化酶活性以及气孔和叶绿体发育。然而，当植物在重度盐胁迫（0.9% NaCl条件）下生长时，SA处理和未处理的植物在生长和生理反应上没有显著差异。因此，我们的研究表明，外源SA可以有效对抗中度盐胁迫对大花剪秋罗生长发育的不利影响。
