Evaluation On Salt And Alkali Tolerance Of Five Legumes

Saline-alkali soil is the distinct type in Songnen Plain,which composed of Na Cl,Na₂SO₄,Na HCO₃ and Na2CO₃.Due to the limitation of the salinization,the major vegetation of distribution is Leymus chinensis community,legumes grow as patches accompany with L.chinensis community.In this study,Medicago sativa,Lotus corniculatus,Melilotus suaveolens,Glycine soja,Lespedeza bicolo were chosen as materials..According to composition of saline-alkaline soil,three molar mass ratios,A?1:9:9:1?,B?1:1:1:1?,C?9:1:1:9?and four concentrations?0m M,40 m M.80 m M.120 m M?were simulated as mixsaline-alkali stress.Overall evaluation the germination and physiological and biochemical indexes in germination stage and seedling stage.The purpose of the study is to explore the potential of these five legume forages to live in saline conditions,and provided reference for the protection and utilization of local pasture resources and the introduction of saline-alkali regions.The results of the experiments are as follows:The five species showed certain adaptability within 0-80 m M,when concentration more than 80 m M,the germination percentage and germination rate decreased significantly,the relative saline-alkali damage and seedlings lethality rised significantly.The seeds can hardly grow normally in group C,which contains more basic salt.The trend of the growth index of five legumes was not obvious within 0-80 m M,and significant changes were observed in over 80 m M.The content of proline and MDA increased significantly at 120 m M,and the root activity and net photosynthetic rate were inhibited.With the increase of saline-alkali stress concentrations and the increase of salinity ratio,the content of Na+ was significantly increased,there was no significant difference in K+content,but the Na+/K+ratio increased significantly.Principal component analysis was conducted on the indexes of germination and seedling physiological,in order to evaluate the saline-alkali tolerance of five species.The comprehensive score ranked from high to low is Melilotus suaveolens,Lespedeza bicolo,Lotus corniculatus,Medicago sativa and Glycine soja.