| With seeds of Atriplex canescens (Pursh),Lonicera tatarica L . Spartium junceum L.)Acer campestre,Staphylea bumaldaDC,Lonicera,Elaeagnus commutate,Fraxinus pennsylvanica as tested materials. Plant growth and physiological parameters were measured in seedlings of eight tree species under different salinity stress (CK, 2‰, 4‰, 6‰). The physiological characteristics of the trees were studied and their salt tolerance abilities were evaluated comprehensively by subordinate function valuemethod. To paint as material Rhus trilobata Nutt, useing DNA molecular markers for the salt tolerance of plants in terms of genetic diversity, the main results were as follows:The results show that the relative germination rate and height of eight trees seedlings are decreased. Fraxinus pennsylvanica after germination, one after another died, all died until the last; with the salt stress concentration increasing, biomass of seven plant are decreased, whereas there was great difference in Biomass among different tree species and parts, it is obvious the decline in root,Elaeagnus commutate,Acer campestre,Staphylea bumaldaDC can not grow normally in 4‰Concentration. With salt concentration increasing, intercellular CO2 concentration have decreasing trend in eight trees seedlings. With the 6‰salt stress transpiration rate decreased rapidly Atriplex canescens (Pursh) Nutt,Spartium junceum L and Lonicera tatarica L, Net photosynthetic of Staphylea bumaldaDC was slight upward trend, and the remaining few are gradually reduced as the salt concentration, it is Basically the same change in Net photosynthetic and stomatal conductance. The value of Fo,Fm,Fv / Fm and Fv / Fo are reduced in six trees seedlings. After salt treatments, the Na+content and K+ / Na+ value in roots, stems and leaves were significantly increased and decreased, respectively. Whereas therewas greatdifference in K+ content among different tree species and parts,and the Na+ content rootswas obviously higher than thatof leaves. The salt tolerances of these seven trees seedlings are evaluated with membership function by detemining the ten physiological indexes. The results show that Spartium junceum L is strongest in salt-resistant, followed by Atriplex canescens (Pursh) Nutt,Lonicera tatarica L,Lonicera,Acer campestre,Elaeagnus commutate,Staphylea bumaldaDC and Fraxinus pennsylvanica.In order to explore the genetic structure of plants after salt stress is Whether changed or not,using SSR molecular markers to paint genetic diversity, genetic variation among populations in Rhus trilobata Nutt was studied. The results showed that: 32 clear and stable electrophoretic bands were obtained from 114 individual genomes in 4 Rhus trilobata Nutt populations by 7 SSR primers, 3 to 8 polymorphic bands could be amplified from each primer, with an average of 4.57 bands, the percentage of intraspecific polymorphic loci (P) was 100%. The total of genetic differentiation coefficient (GST) was 0.0572 in Rhus trilobata Nutt, gene Flow was 8.2390, which showed that the genetic variation was 5.72%, among populations and 94.28%, within populations, and it was more Favorable in gene exchange among populations. As can be seen from the cluster tree ,four populations can be divided into two categories on genetic distance 0.04, CK, 4‰, 2‰3 populations clustered together, 6‰population was clustered into one group. Description of salt stress can make a change in genetic structure of plants and can be selected salt-tolerant genes.
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