Abstract:

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 cultivars. 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 rice. The drought resistance of 10 rice cultivars 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.

Key words: Rice, Drought resistance, Identification index, Flowering stage