摘要： 利用抗旱性不同的1个水稻品种,在干旱棚内通过苗期水分胁迫,研究了可溶性糖、脯氨酸、氨基酸(AA)、谷胱甘肽(GSH)、抗坏血酸(AsA)、可溶性蛋白、丙二醛(MDA)等物质含量及超氧化物岐化酶(SOD)和过氧化物酶(POD)、过氧化氢酶(CAT)活性等生理生化特性的变化.结果表明,苗期水分胁迫下水稻体内可溶性糖、脯氨酸、AA、GSH、AsA、可溶性蛋白、MDA含量增加,SOD、POD和CAT活性增强.相关分析表明,可溶性蛋白、AA、GSH、AsA和MDA含量及SOD、POD和CAT活性的相对值与稻苗反复干旱存活率呈显著或极显著的相关性.因此,水、旱条件下可溶性蛋白、AA、GSH、AsA和MDA含量及SOD、POD和CAT活性的相对值可作为水稻苗期抗旱性鉴定指标.通过逐步回归分析,建立了AsA、MDA和GSH 3项指标的相对值与稻苗反复干旱存活率的最优回归方程,利用最优回归方程对所选用的1个水稻品种进行了抗旱性预测,效果较好.

关键词: 水稻, 水分胁迫, 苗期, 生理生化特性

Abstract: 15 rice cultivars with different drought tolerance were used to study the changes of soluble sugar,proline, free amino acid (AA),glutathione (GSH),ascorbic acid (AsA),soluble protein and malondialdehyde (MDA) contents,and the activities of superoxide dismutase (SOD),catalase (CAT) and peroxidase (POD) at seedling stage in both irrigation and drought conditions. The results indicated that water stress increased obviously the contents of soluble sugar,proline,AA, GSH,AsA,soluble protein,MDA and the activities of SOD,CAT and POD in rice seedlings. Correlation analysis showed that the survival percentage under repeated drought condition was significantly (or very significantly) correlated with the relative values of soluble protein,AA, GSH,MDAt and AsA,and the relative activities of SOD,CAT and POD,which therefore could be used as the evaluation indexes of drought tolerance at seedling stage. The stepwise regression equation of survival percentage under repeated drought condition was established using 3 indexes,the relative contents of AsA, MDA and GSH,which could evaluate effectively the drought tolerance of the 15 rice cultivars.

Key words: Water stress, Seedling stage, Physio2biochemical characters

中图分类号: 

• S11.01