Abstract:

Abstract：Enhancing the rice drought tolerance is an important way for water-saving rice production. To do research on rice drought resistant identification indexes and identification methods is the most important basis for rice drought germplasm improvement. In this experiment, four types of rice varieties were selected in this paper which have significant difference in drought resistance, use three kinds of drought stress treatment, investigate upland rice’s thickness of leaf pulp, thickness of leaf mid-rib, leaf relative water content, and leaf keeping water rate in booting stage, analysis the development regulations of the traits and the relationship between the three types of treatment of rice varieties. The results show that, under drought stress, upland rice’s thickness of leaf pulp, thickness of leaf mid-rib, leaf relative water content, and leaf keeping water rate are significantly higher than lowland rice. Under mild drought，thickness of leaf pulp has significant correlation with drought resistant index DRIm2-B of mature stage biomass, and has correlation with drought resistant index DRIm2-H of booting stage biomass. Under severe drought，thickness of leaf mid-rib has significant correlation with DRIm2-B, and leaf keeping water rate has correlation with yield drought resistant index DRIm2-Y of severe drought. Thickness of leaf mid-rib and leaf relative water content has no significant difference in the four types of germplasm; in booting stage thickness of leaf pulp and leaf keeping water rate can be used as two indexes for drought resistant research and evaluation.