水稻开花期抗旱性鉴定指标的筛选

Screening Identification Indexes of Drought Resistance at Flowering Stage in Rice

水稻抗旱性鉴定指标的筛选已成为水稻抗旱性研究课题的热点之一。本文利用10个水、旱稻品种(组合),在开花期水分胁迫条件下,测定了剑叶叶绿素、脯氨酸、丙二醛、可溶性糖含量、叶片相对含水量、株高、叶面积及光合速率等10项与抗旱性有关的形态和生理指标,进行了主成分分析和逐步回归分析。结果表明,水稻开花期叶片脯氨酸含量、叶片相对含水量、气孔导度、叶面积等4项指标对水稻的抗旱性有显著影响,可作为水稻开花期抗旱性鉴定指标。利用所建立的最优回归方程对供试品种(组合)进行了抗旱性预测,结果与它们在田间表现基本一致,表明用这4个指标在开花期对水稻抗旱性进行鉴定是可行的。

Screening identification indexes of drought resistance has been one of the focuses in study on drought resistance. In this paper, ten indexes correlating with drought resistance including chlorophyll, proline content, MDA content, soluble sugar content, relative moisture content, leaf area and photosynthetic rate in flag leaf and the plant height were monitored under water stress at flowering stage for 10 paddy rice and upland rice eultivars. The identification indexes of drought resistance at flowering stage under water stress were screened by the main content analysis and the step regression analysis. The results showed that at flowering stage, proline content and relative moisture content in leaf, and leaf stomatal conductance and leaf areas significantly influenced the drought resistance and could be the indexes to identify the drought resistance in flee. The drought resistance of 10 rice euhivars was evaluated by stepwise regression equation and the results were basically consistent with the performance in paddy field, which indicated that it is feasible to predict the drought resistance in rice at flowering stage using the four indexes screened out in this study.