披碱草与老芒麦苗期抗旱性综合评价

Comprehensive Evaluation of the Drought Resistance of Elymus dahuricus Turcz. and Elymus sibiricus L. at Seedling Stage

盆栽模拟土壤干旱条件,对采自我国不同生境的披碱草(Elymus dahuricus Turcz.)与老芒麦(Elymus sibiri-cus L.)10份野生种质材料苗期形态学和生理生化指标进行研究,旨在了解干旱胁迫下苗期抗旱特征及其抗旱能力,为披碱草属种质材料抗旱新品种选育、种质资源的开发利用提供理论依据。结果表明,随干旱胁迫日数增加,植株高度、叶面积、相对含水量和叶绿素都明显下降,而电导率、脯氨酸、SOD和POD都明显上升。经抗旱隶属度分析,10份材料抗旱性可分为3类:第一类为相对抗旱,包括SXD1、XJD2、NMD3、NMD4、GSD5、GSS1和JLS2共7份材料;第二类为中等抗旱,包括NMD6和SXS3共两份材料;第三类NMS4为相对易感。经相关分析筛选出对抗旱性影响显著的指标为:相对含水量、叶面积、相对电导率和叶绿素含量。

Elymus dahuricus Turcz.and Elymus sibiricus L.,as the major forages in the world,often suffer from drought to some degree during their growing season.Therefore,the drought-resistant breeding and drought-resistant culture of them should be paid with high attention.At present,the researches in such field mainly concentrate on the collection,identification of the materials and so on,while seldom on the ability of drought resistance.In this study,the drought resistance of 10 wild E.dahuricus and E.sibiricus germplasms from different habitats were investigated using potted plants to simulate soil drought condition.The dynamic indicators related to drought resistance were comprehensive evaluated by the jurisdiction of function law under 21 d of stress.The results show that the plant height,leaf area,relative water content and chlorophyll decreased significantly along with the days of drought stress increased,while the relative electrical conductivity,proline content,SOD,and POD increased distinctly.According to the values of jurisdiction degree,the 10 germplasms were divided into the following three categories.The germplasms with strong drought resistance included SXD1,XJD2,NMD3,NMD4,GSD5,GSS1,and JLS2;the germplasms with medium drought resistance included NMD6 and SXS3;the drought sensitive one was NMS4.Correlation analysis indicate the indices which had significant impact on drought resistance were the relative water content,leaf area,chlorophyll content,and relative electrical conductivity.The results of this experiment could help us understand the characteristics and abilities of their drought resistance and also provide a basis for new species selection and the exploitation and utilization of Elymus germplasm.