水稻开花期耐冷性综合评价及鉴定指标的筛选

利用5个不同类型的水稻品种,在开花期低温胁迫条件下,测定了剑叶叶绿素含量、光合速率、蒸腾速率、可溶性糖含量、脯氨酸含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、丙二醛含量等10项与耐冷性有关的生理生化指标,进行了主成分分析和逐步回归分析。结果表明,水稻开花期剑叶光合速率和SOD酶活性对水稻的耐冷性有显著影响,可作为水稻开花期耐冷性鉴定指标。利用所建立的最优回归方程对供试品种进行了耐冷性预测,结果与它们的结实率表现基本一致,表明用这2个指标在开花期对水稻耐冷性进行鉴定是可行的,用该方法对水稻耐冷性进行综合评价也是可行的。

Comprehensive evaluation and screening identification indexes of cold tolerance at flowering stage in rice

In this paper,ten indexes correlating with cold tolerance including chlorophyll,photosynthetic rate,transpiration rate,soluble sugar content,proline content,superoxide dismutase(SOD) activities,peroxidase(POD) activities,malondialdehyde content were monitored under low-temperature stress at flowering stage for 5 rice cultivars.The identification indexes of cold tolerance at flowering stage under low-temperature stress were screened by the main content analysis and the step regression analysis.The results showed that at flowering stage,photosynthetic rate and superoxide dismutase(SOD) activities had significant influence on cold tolerance and could be selected to identify the cold tolerance of rice.The cold tolerance of 5 rice cultivars was evaluated by stepwise regression equation and the results were basically consistent with the results in their seed seeting rate,which indicated that it was feasible to predict the cold tolerance in rice at flowering stage using the two indexes screened out in this study and the way that this paper used was feasible to comprehensive evaluate the cold tolerance in rice.