| Elytrigia repens (L.) Nevski,the perennial grass of Elytrigia genus of Gramineae, had potential value utilized for good turfgrass and forage, which had plenty of rhizome, strong spreading ability, and good cold-resistance, anti-trample capacity, shade tolerance, humidity resistance and drought resistance. At the same time, Elytrigia repens could be planted on light salt soil and had abundant nutrition value. Xinjiang was a main distributing area of Elytrigia repens in China. On the base of investigating and collecting wild Elytrigia repens germplasm resource in Xinjiang, five introduced materials and thirty-nine native materials in Xinjiang were studied about morphological characteristics, drought resistance (including appraising drought resistance of seed germinating period and seedling period, and response to the droght stress), turf-using characteristic and genetic diversity (including isozyme of EST&POD and DNA by RAPD), which could select good drought-resistance and turf-using materials, understand genetic variation among different materials and provide scientific basis for effective protection and exploitation of germplasm resource, parent selecting in breeding research. The mainly results showed:(1)The morphological characteristics analysis of 16 morphological indexes of 41 E. repens materials showed that the variation of morphological indexes was great among the materials, and the coefficient of variation of morphological indexes were from 4.88% to 33.30%. The variation of the leave level height and the length of flag leaf was great, and that of seed and glumes shape was little. Based on correlation analysis and principal component analysis, five morphological indexes, including number of spikelet, weight of 100 grains, the first node length under the spikelet, leave length, leave level height, were selected as main variation indexes of E.repens, and in according to five indexes, E.repens could be divided into 4 morphological types, including high type, partial high type, special type and dwarf type by cluster analysis, and special type and dwarf type of E.repens could be bred good turfgrass by traditional breeding method.(2) The drought resistance evaluation of E. repens materials in the period of seed germination under PEG stress showed that the germination rate, germination energy, germination index and vitality index of E. repens decreased, and the length of embryonic bud and embryonic root also decreased under PEG stress. According to the comprehensive evaluation of drought tolerance, with the relative germination energy, relative germination rate, relative vitality index, relative embryonic bud length, relative embryonic root length, germination drought-resistance index and germination stress index as evaluation indexes, by membership function method, the sequence of drought resistance of 29 E. repens materials from high to low was E39 > E14 > E11 > E13 > E16 > E03 > E07 > E25 > E34 > E42 > E09 > E29 > E17 > E31 > E21 > E26 > E06 > E10 > E12 > E27 > E38 > E08 > E01 > E04 > E41 >E19 > E37 > E02 > E24。(3) Through measuring the leaf water saturation deficit, water loss rate, electrical conductivity, soluble sugar content and soil water content under drought stress,the drought resistance of 20 E. repens materials was comprehensively evaluated in the seedling period with membership function method. The result showed that the sequence of drought resistance of 20 E. repens materials was E01﹥E14﹥E13﹥E15﹥E17﹥E20﹥E09﹥E16﹥E19﹥E08﹥E18﹥E12﹥E07﹥E04﹥E10﹥E03﹥E06﹥E11﹥E02﹥E05. E01 and E13 collected from yongfeng village, Urumqi in Xinjiang, appeared stronger drought resistance, and could be used in breeding materials of drought resistance.(4) According to the results of drought resistance evaluation in seedling period and observation in the field, four E. repens materials of different drought resistance were selected, including E01,E05,E16,E22, and their physiological response to water stress was studied. The results showed that leaf water saturation deficit(WSD), electrical conductivity(EC), malondialdephyde (MDA )content, proline (Pro) content of E. repens during the drought stress always increased, superoxide dismutasethe (SOD) activity and content of soluble protein showed the tendency firstly decreasing then increasing, and peroxidase ( POD) activity decreased. Compared with other materials, E01 with high drought resistance showed the tendency that WSD increased slowly and the value was low, the maximum value of activities of SOD delayed and had the highest SOD activities, the soluble protein changed little, proline increased little and had a lower MDA content.(5) By grey analysis method, with density, coverage, drought resistance, seedling emergencing time and turf-establishing time as evaluation indexes, evaluation on turf-establishing performance of 20 accesions was carried out. The result showed E11 and E18 had high correlation degree, excellent turf -establishing performance, as were worth being further exploited. Based on the comprehensive assessment system of landscap-performance-utilization and landscape-zoology–utilization,evaluation on the turf-using performance of 20 quackgrass accessions was carried out, the result showed E18 was the best, the following was E04,E08,E09, these materials had potential exploitation and breeding value. By comprehensive assessment, E18,E04,E08 could be used as the primary selection for turfgrass breeding.(6)The results of esterase and peroxidase isozyme from 32 materials of E.repens showed that 16 enzyme belts emerged in sum. Among these belts, the emergence frequency of 10 enzyme belts was high, as meaned that the accessions of E.repens had the similar origin. Based on the esterase and peroxidase isozyme bands, in according to Jaccard similarity coefficient, cluster analysis was done with UPGMA method, 32 materials were divided into 4 categories, the enzyme characteristics of materials collected from altai region, Xinjiang, showed certain correlation with environment condition.(7) Based on the results of RAPD amplification reaction of 32 materials of E.repens, 264 bands were obtained by 18 effective random primers, and the polymorphism rate was 93.7%, which suggested that high DNA polymorphism and abundant genetic variation among E.repens materials existed. By clustering analysis based on RAPD, at the point of genetic similarity coefficient 0.373, all materials could be divided into 5 categories, and the categories had a certain correlation with environment condition.(8)Through study on morphological characteristics, drought resistance, turf-using characteristic and genetic diversity of wild Elytrigia repens (L.) Nevski in Xinjiang, the result showed great variation existed for different characteristics among accessions, abundant genetic diversity also existed among accessions, As had the value to be exploited, high drought resistance accessions and excellent turf–using accessions obtained by selection made the base for new quackgrass line breeding...
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