外源水杨酸对干旱胁迫下花椰菜叶片抗氧化作用的影响

Effect of Exogenous Salicylic Acid on Antioxidant Capacity in Cauliflower Leaves Under Drought Stress

以花椰菜为试材,采用大田人工控水设置田间持水量的35%、50%和65%3个灌水下限,通过叶面喷施0.1 mmol/L水杨酸(SA),研究外源SA对花椰菜叶片抗氧化能力的影响。结果表明:SA可提高叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)等抗氧化酶活性,同时减缓花椰菜叶片中丙二醛(MDA)积累和细胞膜透性的持续增大,增加游离脯氨酸(Pro)和还原型谷胱甘肽(GSH)在叶片中的积累。因此,SA能够提高干旱胁迫下花椰菜的抗旱能力,提高花椰菜叶片中抗氧化物质的活性,增加渗透调节物质的含量,减少膜脂过氧化作用,在一定程度上可缓解干旱对植物造成的伤害。

The experiment was conducted with cauliflower to study the influence of exogenous salicylic acid （SA） on oxidation resistance of cauliflower in the field, which set three lower irrigation limits of water control, that was 35%, 50%, 65% of field capacity. The result showed that SA could increase the activity of superoxide dismutase （SOD）, peroxidase （POD）, catalase （CAT） and ascorbic acid peroxidase （APX）. Meanwhile, SA reduced accumulation of cauliflower leaves malondialdehyde （MDA） content and continuously increased cell membrane permeability, increased accumulation of free proline （Pro） and glutathione （GSH） in cauliflower leaves. Therefore, under drought stress, SA could improve the drought resistance ability and antioxidant activity, increased content of osmo To some extent, SA could alleviate regulation substance of cauliflower, reduced lipid peroxidation of membrane. the drought damage on Plant.