野生垂穗披碱草种质资源抗旱性筛选与评价

Screening and Evaluation of Drought Resistance of Wild Elymus nutans Griseb.

为探究垂穗披碱草(Elymus nutans Griseb.)苗期对干旱胁迫的响应,筛选出耐旱材料,本试验选取内蒙、甘肃、四川等不同地区不同生境来源的9份野生垂穗披碱草种质材料为研究对象,采用自然干旱法对垂穗披碱草幼苗进行为期35 d的干旱复水处理。通过分析幼苗叶片的形态表型和生理指标的含量变化,采用隶属函数法和聚类分析综合评价了9份垂穗披碱草的抗旱性。研究发现:在干旱胁迫下,9份垂穗披碱草的植株表型和生理特性均受到不同程度的影响,表现为叶片相对含水量、叶绿素含量和最大光化学效率(Fv/Fm)下降,细胞膜透性和抗氧化酶活性升高以及渗透调节物质的积累。9份垂穗披碱草的抗旱性强弱顺序依次为NM037>XJ027>HB013>XZ010>GS007>QH011>GS005>SC021>SC020。本研究表明,材料NM037能更好地适应干旱胁迫的处理,表现出更强的抗旱能力,可作为抗旱型垂穗披碱草育种的参考对象,这为人工草地建植、草地生产力的提高和生态修复提供依据。

In order to explore the response of seedling stage of Elymus nutans Griseb.to drought stress and screen out drought-tolerant materials,the germplasm materials of 9 wild plants from different habitats(Inner Mongolia,Gansu,Sichuan and other regions)were selected as the research objects.The seedlings of Elymus nutans Griseb.were treated with natural drought for 35 days.By analyzing the changes of morphological and physiological indexes of seedling leaves,the drought resistance of 9 plants was evaluated by membership function method and cluster analysis.The results showed that the phenotypes and physiological characteristics of 9 plants were affected at different degrees under drought stress,including the decrease of chlorophyll content and maximum photochemical efficiency(Fv/Fm)in leaves,the increase of cell membrane permeability,antioxidant enzyme activity,and the accumulation of osmoregulatory substances.The order of the drought resistance of 9 materials was:NM037>XJ027>HB013>XZ010>GS007>QH011>GS005>SC021>SC020.The results showed that NM037 better adapted to drought stress,and showed stronger drought-resistant ability.It could be used as a reference object for breeding drought-resistant,and provide basis for improving the productivity and ecological restoration of artificial grassland.