Screening Germplasms Of Thinopyrum Ponticum With Salt Resistance

In order to improve marginal soil and rich grass varieties of coastal zone,Our study used seven populations of Thinopyrum ponticum?Podp.?Barkworth and D.R.Dewey[=Agropyron elongatum ssp.ruthenicum Beldie;Elytrigia pontica?Podp.?Holub;Lophopyrum ponticum?Podp.?áL?ve]as materials,measured phenomenon,physiological and biochemical index of germination stage,seedling stage and growth stage.The results are as follows:?1?Germination test was deal with 250 mM NaCl.The result is that the relative germination rate?RGR?and relative germination potential?RGP?of Grass 2 were 91.65%and 76.36%,respectively.And the top among these seven populations.Grass 6,Grass 3 and Grass 2 were top three in total membership function of germination stage.?2?The salt tolerance of seven populations of seedling stage were compared by soil culture with 0%,0.8%and 1.6%salt content.The result showed that when salinity stress became more severe,the superoxide dismutase?SOD?,peroxidase?POD?,ascorbate peroxidase?APX?and catalase?CAT?gradually increases,the electric conductivity?EC?and malondialdehyde?MDA?decreases,the content of H₂O₂ decreased initially and than increased.The Grass2 had lower damage to leaf cell membrane,higher activity of antioxidant enzymes and higher grass yield.Besides,it was found that Grass 2 ranked first by the membership function calculation in these three environments.?3?The salt tolerance of growth stage of seven populations were compared in field condition with 0.3%and 0.5%salt content.The result is that Grass 2had higher plant height?PH?,tiller number?TN?,spike number?SN?,spikelet number per spike?SNPS?,leaf fresh weight?LFW?and shoot fresh weight?SFW?,and the fresh weight and the dry weight of Grass 2 were highest than those of most of other grass populations.The average of content the crude protein?CP?was 13.37%,neutral detergent?NDF?and acid detergent?ADF?were 56.21%and 30.24%,respectively.There was no significant difference in these nutritive indexes.Grass 2 had the highest tannin content?TC??2.29 mg/g FW?.There were no significant correlation between iron content and grass yield.The iron content were in the middle level in seven populations.The result of total membership value of agronomic traits and grass yield showed that the Grass 2 was the best in four conditions.?4?Grass 2 was planted in field?0.3%salt content?with different density and irrigated by brackish water.The result showed that when the planting density of 30 cm×10 cm and 30 cm×40 cm,Grass 2 had higher fresh weight.Meanwhile,using Scanalyzer 3D,Grass 2 settled by 1.2%salt content and its object extent Y,biomass,object extent X,area,compactness,excentricity,side caliper length,mean color green and top caliper length were assessed.The result showed that Grass 2 had good phenotype parameters.Above all,the synthetic salt resistance of Grass 2 was the best.Our study provide theoretical basis and germplasms for the innovation of salt resistance and high quality forage.