Comprehensive evaluation of the drought resistance of Elymus dahuricus Turcz. and Elymus sibiricus L. at seedling stage.

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.