丛枝菌根真菌对盐胁迫下黄瓜幼苗渗透调节物质含量和抗氧化酶活性的影响

以盐敏感型黄瓜品种‘津春2号’为材料,研究了丛枝菌根真菌(AMF)对盐胁迫下黄瓜幼苗生长及叶片、根系中渗透调节物质含量和抗氧化酶活性的影响.结果表明:(1)在盐胁迫条件下,黄瓜幼苗生长受到明显抑制,其株高、地上部、地下部干鲜重均明显减小,同时体内可溶性蛋白、可溶性糖、脯氨酸和MDA含量,以及O2(÷)产生速率和SOD、POD、CAT活性均比对照显著升高.(2)盐胁迫下接种AMF可显著促进黄瓜植株的生长,进一步提高黄瓜幼苗体内可溶性蛋白、可溶性糖和脯氨酸含量及SOD、POD、CAT活性,而显著降低MDA含量和O2(÷)产生速率.研究表明,AMF可通过显著促进盐胁迫下黄瓜幼苗体内渗透调节物质积累和抗氧化酶活性提高,有效降低体内膜脂过氧化水平,从而缓解盐胁迫对植株的伤害,增强黄瓜幼苗对盐胁迫的耐性.

Effects of Arbuscular Mycorrhizal Fungi on Osmoregulation Substance Contents and Antioxidant Enzyme Activities of Cucumber Seedlings under Salt Stress

The effects of arbuscular mycorrhizal fungi(AMF) on osmoregulation substance contents and antioxidant enzyme activities in cucumber varieties ’Jinchun No.2’ under salt-stress were studied in greenhouse.The results showed that:(1)soluble protein,soluble sugar,proline and malondialdehyde(MDA) contents,superoxide anion(O-·2) production rates,superoxide dismutase(SOD),peroxidase(POD) and catalase(CAT) activities in cucumber seedlings under 0.6% NaCl salt-treatment were higher than that of control;(2)Under salt stress,after AMF-inoculation,soluble protein,soluble sugar and proline contents,SOD,POD and CAT activities further increased,while MDA content and O-·2 production rate decreased;under non-salt stress,AMF-inoculation significantly increased soluble protein,soluble sugar and proline contents,SOD,POD and CAT activities,while MDA content and O-·2 production rate were as same as control in cucumber seedlings.AMF could enhance the seedlings osmotic adjustment mechanism of salt tolerance,raise the activities of antioxidant enzymes,decrease the membrane lipid peroxidation.So the damage of salt stress on the plant would be alleviated and the adaptability of cucumber seedlings to salt environments would be improved.