采用外源水杨酸(SA)叶面喷施的方法,研究不同浓度SA(0、0.1、0.5、1.0、1.5 mmol/L)对盐胁迫下小白菜(Brassica chinensis)‘上海青’幼苗生长及其生理生化特性的影响。结果表明,0.5 mmol/L SA诱导能显著提高幼苗的株高、单株干重、叶面积和含水量等;降低叶片丙二醛(MDA)含量和电解质渗出率;增强叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的活性。说明适宜浓度的外源SA可以通过提高植株渗透调节能力和抗氧化能力,保护膜结构和功能,减轻盐胁迫对小白菜的伤害。本试验表明,SA最佳诱导浓度为0.5 mmol/L。

The experiments were performed to investigate the effects of exogenous SA on the physiological parameters in Chinese cabbage under NaCl stress.Chinese cabbage seedlings were treated by foliar spray of 0, 0.1, 0.5, 1.0, 1.5 mmol/L SA, and were then subjected to NaCl stress.Results indicated that 0.5 mmol/L SA significantly improved the plant height, plant dry weight, root thickness, leaf area and significantly reduced the leaf malondialdehyde (MDA) content and electrolyte leakage rate, significantly enhanced superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and other plant cell protective enzyme activity of leaf.Appropriate concentration of exogenous SA could reduce the stress on the cabbage injuries by increasing plant osmotic adjustment ability, antioxidant capacity and protecting the membrane structure.The best treatment concentration of SA was 0.5 mmol/L.