水杨酸对根际高温胁迫下黄瓜生理特性的影响

Effects of salicylic acid on physiological characteristics of cucumber under high rhizosphere temperature stress

以黄瓜‘春秋王二号'为材料,研究了0.05—0.20 mmol/L水杨酸(SA)对35℃根际高温胁迫下黄瓜幼苗叶片活性氧代谢和渗透调节物质含量的影响。结果表明:除0.20 mmol/L处理会降低脯氨酸(Pro)含量外,其他不同浓度水杨酸溶液均可显著降低超氧阴离子(0_2·^-)产生速率、丙二醛(MDA)含量和电解质渗透率(EL);显著提高了超氧歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性以及可溶性蛋白和脯氨酸(Pr0)含量。外源水杨酸缓解苗期根际高温胁迫具有剂量效应,以0.1 mmol/L的SA缓解根际高温造成的膜脂过氧化伤害效果最好。

The cucumber cultivar ‘Chunqiuwang 2’was used as a test material,and the effects of 0.05—0.20 mmol/L salicylic acid（SA）on the cucumber seedling leaves’reactive oxygen metabolism and osmoregulato-ry substance content were investigated at 35 ℃ rhizosphere temperature.The results showed that different-con-centration SA treatments could significantly decrease the superoxide anion（O2·-）producing rate,malonaldehyde （MDA）content and electrolyte leakage（EL）,and also significantly improve the activities of superoxide dismutase （SOD）,peroxidase （POD ）,catalase （CAT）and the contents of proline and soluble proteins except the 0.20 mmol/L SA treatment making the proline content decrease.Exogenous SA had a dosage effect on alleviating the membrane lipid peroxidation caused by high rhizosphere temperature,and 0.1 mmol/L SA has the best effect.