| We used perennial ryegrass cv. Medalist Gold which could endure low-temperature and cynodon dactylon cv. Jackpot which could endure high-temperature for the Experimental materials From the morphological, physiological and biochemical indicators of change and paraffin-embedded slide-cutting method to explore the reason how the two types of turfgrass were hurted under temperature stress and their difference, to improve the intolerance to temperature stress,and show the compare materials for furture research.The results were showed as followed.1 We could see that the best temperature for the Perennial ryegrass is between 15 and 20℃from obserating the morphological indicators, It had the highest of roots, coverage, density, color,which was the best quality of temperature, under different temperatures, the root, density, coverage, color had both very significant correlation that can be used as the cool-season grass indexes under difference temperature, the best temperature for the Cynodon dactylon was 20-25℃,which had the density, the maximum coverage, greater color.under different temperatures, the root, density, coverage, color, the wax was notable both highly relevant and could be used as warm-season grass indexes under difference temperature.2 From the physiological and biochemical indicators,the optimum temperature for Perennial ryegrass growth between 15 and 20℃. In comparison, the 10 and 5℃belong to Low temperature stress and the 25,30,35℃belong to high temperature stress; and the optimum temperature for Cynodon dactylon growth between 20 and 25℃. In comparison, the 15 and 10℃belong to Low temperature stress and the 30,35℃belong to high temperature stress.3 At 5℃,the SOD of the average growth rate of the activit SOD of the leaf of Perennial ryegrass was 193%, antioxidant enzymes were at a high level, proline content had the average growth rate of 73.2%. electrolyte leakage was only increased of 26.3 %. membrance was less hurt than high temperature; at 35℃, the average growth rate of the activity of SOD of the leaf of Cynodon dactylon was 142%, the average growth rate of the activity of SOD of the leaf of Cynodon dactylon was 292%, Antioxidant enzymes were maintained at a high level, proline accumulation was more and electrolyte leakage was less, the permeability of the membrane only an increase of 27.5%, the membrane system was hurt lessly below under low temperature.4 The reason that Cynodon dactylon which couldn't endure low-temperature incomprison to Lolium perenne L. was that the Response of the activity of antioxidant enzymes was fast under high-temperature. But with the extension of time to stress, the activity of antioxidant enzymes was Significantly lower ,lipid peroxidation level to deeper and accelerated the superoxide free radicals, the electrolyte leakage rate of Leaves increased significantly, membrane was degree victimed;the reason that Perennial ryegrass which couldn't endure high-temperature incomprison to Cynodon dactylon was that the Response of the activity of antioxidant enzymes was less under low-temperature. But with the extension of time to stress, the content of Pro the response of the content of Pro was less under low-temperature. But with the extension of time to stress, Pro was Significantly lower ,lipid peroxidation level to deeper and accelerated the superoxide free radicals, the electrolyte leakage rate of Leaves increased significantly, membrane was degree victimed.5 The result by means of paraffin-embedded slide-cutting method showed that, the high temperature on Perennial ryegrass hurted seriously. Mesophyll cells was injuried heavier, the Chloroplast significant reduction in the number of cells;low temperature on Cynodon dactylon hurt seriously,Mesophyll cells could not be seen clear boundaries, the membrane was collapsed, most of the nucleus disappear, we could not see the Chloroplast of particles.
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