提高苦荞麦水分利用效率的生理机理研究

As more attention paid on the dietary nutrition, increasing grain yield of crops like tartary buckwheat with supplement nutrients to diet structure is becoming more and more important. With global shortage of water resources, how to efficiently use the limited water resources to maximize agricultural production has become the focus of global concern. Previous results show ed that there are differences between different genotypes of tartary buckwheat varieties in water use efficiency and yield, but the physiological and ecological mechanism is unclear. Based on previous results, different genotypes are selected as research material, we will study the soil moisture on space and its dynamic variation, root system characters, physiological characteristics, root hydraulic signal characteristics, and water use efficiency at different aspect. Through this study, we want to clarify the relationships between soil water characters, root characters and water use efficiency, to find the key root traits, physiological characteristics affecting water use efficiency, to elucidate physiological mechanism of improving water use efficiency, and to give guidance to how to improve water use efficiency to other crops. Further more, we want to make contribution to water saving culture on tartary buckwheat.

随着人们对膳食营养重视度加剧，提高荞麦等营养成分全面的作物产量以补充膳食结构显得越发重要。在全球水资源严重匮乏的环境压力下，如何高效地利用有限的水资源进行最大限度的农业生产成为全球关注的焦点。前期研究结果表明，不同基因型苦荞麦品种水分利用和产量存在差异，但其水分高效利用生理生态机理尚不清楚。本研究拟在此基础上以不同基因型苦荞麦为研究对象，通过研究不同基因型苦荞麦根系土壤分布、动态变化、根系性状、生理特性、根系水利信号特征、及不同层面水分利用效率，探讨土壤特性、根系特性与水分利用的关系，找到影响苦荞水分利用率的关键根系性状、生理特性，以阐明苦荞麦高水分利用效率的生理机理机制，为提高其他作物水分利用效率提供参考，也为下一步探讨苦荞麦节水栽培奠定基础。

苦荞是一种极为重要的药食两用杂粮作物。然而由于主产区水资源不足，如何高效地利用有限的水资源成为全球焦点。以前不同基因型苦荞为研究对象，阐述了逐渐干旱下苦荞麦根系性状、根系信号特征变化，发现逐渐干旱时晋荞2号（高抗品种）nHRS阈值范围（TR）宽，非水力信号、水力信号出现时间较川荞1号（敏感型品种）早，提前调动植株适应机制，促使叶片出现暂时萎蔫和永久萎焉出现的时间滞后；而干旱时高抗品种具有较大根体积和根表面积，利于水分吸收；探明了不同基因型苦荞麦耗水量及瞬时水分利用率，发现晋荞2号在干旱各信号点具有较高叶片水分利用效率和较低的蒸腾作用，从而全生育期耗水量低于川荞1号；探明以黄酮、芦丁、槲皮素等根源信号物质响应干旱胁迫的变化规律，并而代谢组学发现黄酮类化合物含量上升，黄酮和黄酮醇生物合成表达增强，因此推测苦荞通过黄酮与黄酮醇生物合成途径调控黄酮类根源信号的表达。本研究从生理生化、代谢水平探讨了提高苦荞水分利用效率的机理，为苦荞水分利用效率研究奠定了基础。