花生根系形态特征与抗旱性及水分利用率的关系

Drought is a limiting factor for peanut yield and quality improvement. Root is the main organ of plant water uptake.The bucket planted exploratory experiment showed that peanut root grown to deeper soil and increase the root surface area and volume in deeper soil under drought stress.This study was to establish a in situ root observation method through different root observation method on the preliminary research. Using the suitable method for in situ root observation to study the root morphology of the different drought tolerance peanut varieties under drought stress. The root physiological and biochemical indexes changes were also studied.The relationships of peanut root morphological development with drought tolerance and water use efficiency were studied. The study of the relationships had a very important role for further understanding peanut water absorption,transporting, using, lossing mechanisms and the cultivation of different drought tolerance peanut varieties. This study would help to understanding the adaptive mechanism of root water absorption and utilization of different drought tolerance peanut varieties, and provide a theoretical basis for regulation of peanut efficient water using.

干旱是花生产量和质量提高的限制因子。根系是植物吸水的主要器官，利用桶栽探索性试验表明干旱胁迫下下花生根系向深层土壤生长，且增加深层土壤内的根系表面积和体积。本研究拟在前期研究的基础上，通过多种根系形态观测方法的研究建立田间花生根系形态原位观测方法，应用该方法研究干旱胁迫下抗旱能力不同的花生品种的根系形态发育特征及其生理生化指标的变化，并对不同花生根系形态发育类型与抗旱性及水分利用率间的关系进行研究。研究花生根系形态的发育特征与抗旱性及水分利用率的关系对进一步理解花生的水分吸收、运输、利用和散失机制以及培育抗旱性花生具有非常重要的作用。本研究有助于理解不同抗旱性花生品种根系水分吸收与利用的适应性机制，为调控花生水分高效利用提供理论基础。

干旱是花生产量和质量提高的限制因子之一。根系是植物吸水的主要器官，通过自身形态和生理生化特征的调整以适应变化后的土壤水分环境。在基金的资助下，我们筛选得到6个抗旱型花生品种和4个干旱敏感型品种；通过3种根系观测方法的比较表明土柱栽培法适合干旱胁迫下花生根系形态的观测。研究表明抗旱型品种根系较发达，具有较大的根系生物量、总根长、总根系表面积；干旱胁迫使抗旱型品种根系总表面积和体积增加，干旱敏感型品种则相反，且干旱胁迫下抗旱相关基因表达增加；总根长、根系表面积和0~20 cm土层内根系对产量及水分利用率提高具有非常重要的作用。土壤水分亏缺条件下，花生主要通过增加深层土壤内根长、根系表面积和体积等形态特性，积累可溶性糖和脯氨酸类渗透调节物质、增加抗干旱胁迫相关基因表达等机制调节植株对水分的利用。本研究为进一步理解不同抗旱性花生品种根系水分吸收与利用的适应性机制，调控花生水分高效利用提供理论基础。