【作者】 马均； 李敏； 傅泰露；

【Author】 Ma Jun Li Min Fu Tai-lu (Rice Research Institute of Sichuan Agricultural University,Wenjiang 611130,Sichuan,China)

【机构】 四川农业大学水稻研究所；

【摘要】 以5个不同类型杂交水稻品种为材料,通过人工气候箱开花期高温胁迫,测定了剑叶的光合速率、叶绿素、可溶性糖、游离脯氨酸、MDA 的含量及保护性酶活性变化。结果表明,水稻开花期高温胁迫降低了叶片光合速率、叶绿素含量,增加了可溶性糖、游离脯氨酸、 MDA 含量及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)的活性。通过相关分析表明,开花期高温胁迫与对照条件下的叶绿素、游离脯氨酸、MDA 含量和 SOD 活性的变化幅度与品种的热敏感指数呈显著或极显著相关性,因此,高温下的叶绿素、游离脯氨酸、MDA 含量和 SOD 活性的变化幅度可作为水稻开花期耐热性生理鉴定指标。对此4项指标变化幅度与热敏感指数进行逐步回归分析,所建立的回归方程可预测水稻开花期耐热性。更多还原

【Abstract】 Rice plants may suffer serious heat stress during its growth period,which will affects the process of physiological metabolic activity of the plants.Five different types of rice cultivars were used as experimental materials.Changes in photosynthesis rate,chlorophyll content,soluble sugar content,free proline content,malondialdehyde (MDA) content and antioxidative enzyme activities were studied under both high temperature and normal conditions at flowering stage.The results indicated that high temperature stress decreased leaves’ photosynthesis rate,contents of chlorophyll, increased contents of soluble sugar content,free proline content,malondialdehyde (MDA) content,as well as the activities of superoxide dismutase (SOD),catalase (CAT) and peroxidase (POD) in leaves at flowering stage.Correlation analysis showed that heat susceptibility index significantly or very significantly correlated with relative changed percentage of contents of chlorophyll,free proline, MDA and SOD activity under both high temperature and normal conditions.Therefore,they could be selected as physiological identification indexes for heat tolerance at flowering stage in rice.Using stepwise regression equation to evaluate the heat tolerance of rice cultivars was considered scientifically and reliably.更多还原