Salt Tolerance Evaluation And Physiological Mechanism Of Seashore Paspalum

Increasing soil salinization has become a global issue.Soil salinization in China has a large area and a wide range,which has a serious impact on the development of agriculture in several 1 regions.Seashore paspalum(Pasplum vaginatum)is a strong salt tolerant material in turf grass.Therefore,it is of great significance to study the salt tolerance difference and the physiological mechanism of salt tolerance of different species of Paspalum.In this study,bermudagrass,zoysia grass and 56 paspalum metarials were exposed for 500 mM NaCl salt treatment to determine the apparent quality and percentage of withered leaves,and to primarily analysize salt tolerance difference among different materials and selected three materials(647915?647921 and SP005).Accoring to above cluster analysis result,0 mM,300 mM and 600 mM NaCl were used to determine the relative water content,electrolyte leakage,shoot height,growth rate,shoot biomass and sodium and potassium content,and to explore the physiological mechanism of salt tolerance for different salt tolerant materials(647915,647921 and SP005).The main results are as follows:The results of determination and cluster analysis of 58 materials of turf grass apparent quality and percentage of withered leaves showed that the 58 materials were divided into three categories:the first category was salt sensitive materials,a total of 21,and the apparent quality score of turf grass was 0-2 after 67 d treatment,and the second species belonged to salt resistant strong materials,a total of 6,after 67 d.The apparent quality scores were 6;the third category belonged to medium salt tolerant materials,29,and the apparent mass score of turfgrass was 3-5 when salt stress was 67 d.The results of the growth morphology,physiology and ion content of three paspalum materials under salt stress showed that salt stress had a positive effect on the apparent quality of the leaf,relative water content,the electrolyte leakage rate,shoot height,growth rate,biomass and Na+and K+content of leaf of three materials.And with the increase of salt concentration,the degree of damage is more serious.However,three paspalum had different physiological responses to salt stress,showed under 600 mM NaCl treatment for 21 days.Compared with SP005 and 647921,the relative water content,growth rate,shoot biomass,electrolyte leakage and Na+content in leaves of 647915 were significantly different.The salt tolerance of three species of Paspalum metarials was 647915>SP005>647921.In conclusion,this study lays a foundation for further screening and breeding new varieties of salt tolerant seashore paspalum.