外源抗坏血酸对水稻抗铝生理指标的影响

为探讨外源抗坏血酸（AsA）对水稻的抗铝性能的影响,以‘滇优35号’（杂交稻,粳稻）为试验材料,采用溶液培养法研究外源AsA对铝胁迫下水稻根尖H₂O₂、内源AsA、GSH、可溶性蛋白、脯氨酸含量及抗氧化酶活性等生理生化指标的影响。结果显示,与对照相比,铝胁迫导致水稻根尖可溶性蛋白和内源AsA含量减少,而MDA和H₂O₂含量,SOD、POD、APX和CAT活性,GSH及脯氨酸含量增加;外源AsA可增强铝胁迫水稻根尖的脯氨酸及可溶性蛋白等含量,内源AsA、GSH含量及SOD、POD、APX、CAT活性,而降低MDA和H₂O₂含量。表明外源AsA通过调控抗氧化酶活性,提高渗透调节物质含量和抗氧化物质含量来降低H₂O₂的积累,从而缓解铝胁迫下水稻质膜氧化程度,增强水稻的抗铝性能。

Effects of Exogenous Ascorbic Acid on Physiological Indexes in Rice Under Aluminum Stress

In order to investigate the effect of exogenous ascorbic acid(AsA)on aluminum resistance of rice,the‘Dian Superior 35’(Hybrid,Japonica)was used as the hydroponical test material to study the influence of the physiological and biochemical indicators such as the contents of H₂O₂,endogenous AsA,GSH,the soluble protein,proline and the activity of the antioxidant enzyme,etc.in the rice root tips.The results showed that compared to the control,the contents of the soluble protein and endogenous AsA in the root were decreased,while the activities of SOD,POD,APX and CAT,the contents of MDA,H₂O₂,GSH and proline were significantly increased under aluminum stress,respectively,the exogenous AsA migth improve the contents of proline,the soluble protein,endogenous AsA and GSH,the activities of SOD,POD,APX and CAT,respectively,and decreased the contents of MDA and H₂O₂.The above results showed that exogenous AsA might alleviate the degree of the plasma membrane oxidation and promote aluminum resistance of rice by enhancing the activities of the antioxidant enzyme,the contents of osmoregulation substances and antioxidant substance which might reduce the accumulation of H₂O₂.