栽培稻叶结构、水分生理与抗旱性关系研究

Leaf Structure and Water Physiology of Rice (Oryza sativa L.) and the Relationship with Drought Resistance

增强栽培稻品种的抗旱性是稻作节水生产的重要途径。稻作种质资源抗旱相关指标的研究是改良稻作品种抗旱性的重要依据。选择抗旱性差异明显的四种类型稻作种质,采用三种干旱胁迫方式,对孕穗期植株叶片的叶肉厚、中脉粗、叶片相对含水量及叶片保水率进行了考察,分析稻作种质在三种处理下各性状相互之间的内在关联及其与品种抗旱性的关系;结果表明叶肉厚、中脉粗、叶片相对含水量及叶片保水率在干旱胁迫下均表现为旱稻类型高于水稻类型。轻度干旱下的叶肉厚与成熟期生物量抗旱指数DRIm2-B极显著相关,与孕穗期生物量抗旱指数DRIm2-H显著性相关。重度干旱下的中脉粗与DRIm2-B极显著相关,重度干旱下的叶片保水率与重度干旱产量抗旱指数DRIm2-Y显著相关,中脉粗和叶片相对含水量在四种种质类型中差异不明显;孕穗期叶肉厚和叶片保水率可分别作为稻作种质抗旱性研究和评价的两个指标。

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.