| New zyosia grass- Shanghai JD-1 Zoysia, breeded by Research Centre of Pratacultural Science, Shanghai Jiao Tong University. Split-Plot Design experiment with there factors: water stress ( three level: light, moderate and heavy ), traffic stress ( three level: no, moderate and heavy ) and nitrogen application ( three level: 0g/㎡ for no nitrogen application, 8g/㎡ for moderate nitrogen application and 16g/㎡ for heavy nitrogen application). The growth index, physiological index and photosynthesis index of the zyosia grass were surveyed, the effects of water stress, traffic stress and nitrogen application on the growth and development of zyosia grass and the relations of them were studied in this experiment, the results showed as fellows:1 Zoysia grass growth was restricted by water stress whereas the harm caused by water stress was weakened though physiological and biochemical modulation Zoysia grass owned.Under water stress, the density, the height and the biomass of zoysia grass went down, which became more serious as the stress strengthened.The relative conductivity, the proline content and the MDA content of Zoysia grass leaves increaed gradually as the extension of the experiment time in the condition of no water stress; while the response of ascend-descend-ascend was appeared when either light or heavy water stress was presented.The density, the height and the biomass of zoysia grass increased within the recovery phrase. Compared with the zoysia grass grown in the area of no water stress, both the density and the biomass of zoysia grass grown in the area of water stress were higher, and the relative conductivity, the proline content and the MDA content of zoysia grass leaves were lower. There are no significant differences of all different indicators between the the zoysia grass under light water stress and that under heavy water stress.2 Under water and traffic stress, the harm of zoysia grass caused by water stress was promoted along with traffic stress, showing the physiological and biochemical index change a lot, but their inclination were consistent.Under water and traffic stress, the growth and physiological index of zoysia grass had a big range. Generally speaking, the traffic stress made the injure of the zoysia grass bearing water stress become more serious, but the change graph was consistent with that of water stress.Under the same condition of water stress, when the traffic stress was strengthened, the density, the height and the biomass of zoysia grass went down; whereas, the relative conductivity, the proline content, the MDA content and solubility sugar content went up.Under the same condition of traffic stress, when the water stress was strengthened, the density, the height and the biomass of zoysia grass went down except that grown in light water stress area, whose density and biomass showed bigger. As the extension of water stress time, the relative conductivity, the proline content, the MDA content and solubility sugar content of the leaves of the zoysia grass had a change graph of ascend-descend-ascend3 zoysia grass growth was promoted significantly by the application of nitrogen, but the absorbability to nitrogen was different under different water stress.Under the same condition of water stress, as the nitrogen application increased, the density, the height and the biomass of zoysia grass went up; at the early stage of nitrogen application, the relative conductivity, the proline content,the MDA content and the solubility sugar content of the leaves went up; while, at the late stage and during the recovery phrase, these indexes show a negative relation with the increment of nitrogen application.Under different conditions of water stress, along with the increment of water stress, the density, the height and the biomass of zoysia grass went dowm, but the relative conductivity and the solubility sugar content of the leaves also went up. The proline content and the MDA conten of the leave of the zoysia grass cultivated with light water stress were lower than that with no water stress, this phenomenon also appeared when tested those cultivated with light water stress and those cultivated with no water stress.4 Zoysia grass growth indicated differently under effects of nitrogen treatment on the water stress or traffic stress.Without water stress, the density, the height and the biomass of zoysia grass went up along with the increase of nitrogen application; the relative conductivity, the proline content,the MDA content and the solubility sugar content of the leaves went down under the condition of no or moderate traffic stress, but under heavy traffic stress, they went up, as the increment of nitrogen application.Under light water stress, with the treatment of moderate or heavy traffic stress, moderate nitrogen application, the density and the height of zoysia grass were bigger than that with no or numerous nitrogen application; with the treatment of moderate or heavy traffic tress, the relative conductivity, the proline content,the MDA content and the solubility sugar content of the leaves of the zyosia grass with the moderate nitrogen application showed higher rather than that with the numerous nitrogen application.Under heavy water stress, the density, the height and the biomass of zoysia grass with nitrogen application were bigger than that with no nitrogen application, and that with moderate nitrogen application were also better than that with numerous nitrogen application. No matter what traffic stress was treated with, the relative conductivity, the proline content,the MDA content and the solubility sugar content of the leaves were increased along with the increment of nitrogen application. 5 The evaluation of the effects of water, traffic stress and nitrogen treatment on the zoysia turf quality and their relations with the turf maintainingBy Grey Relational Analysis to the growth and physiological indexes of zoysia grass under different treatments of water, traffic stress and nitrogen levels, the results were indicated:For the turf under the traffic stress, light water stress had little effect on the growth and development of the zoysia grass, all indexes were moderate, it showed zoysia grass had stronger traffic tolerance under light water stress than other water stress.For the zyosia grass lawn under the traffic stress, the traffic tolerance of zoysia grass could be increased with all levels amount of nitrogen application. Under the moderate traffic stress, moderate nitrogen application promoted the growth and the development of zoysia grass for which would provide suitable indexes of physiological resistance and reinforce the traffic resistance for the zyosia grass. Under the heavy traffic stress, nitrogen application would aggravate the stress injure of the zyosia grass and give no help for the traffic resistance of the zyosia grass.For the zyosia grass lawn under water stress, nitrogen should be applied accordingly to the stress level to catch the goal of rational manuring and effective management. Under the moderate water stress, both moderate and numerous nitrogen application were able to promote the growth and the development of zyosia grass and maintain its good character for lawn usage. Under the heavy water stress, instead of making an obvious positive effect for the growth of zyosia grass with nitrogen application, it increased the viscosity of soil solution, which have an negative contribution to the growth and the development of zyosia grass.
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