Urbanization requires development of proper landscape but water is a limiting factor for this purpose especially in dry regions of the world such as in many parts of Iran . Using drought resistant plants in landscape design is one of the main proposed method to overcome this problem. Turf grasses are desired kind of land cover in landscape development. Generally this kind of vegetation cover requires large amounts of water and because of shallow and frequent irrigation most of applied water is lost in to the air by evaporation. Introducing proper grasses for land cover with drought resistance ability is very useful for water conservation in dry areas. In this research five species, varieties and population including erennial ryegrass and mix sport, also Cynodon dactylon × C.transvalensis (tifway), C.dactylon (88-khl) and crested wheatgrass were used for comparison of plants ability to with stand moisture stress. Seeds or plant propaguls were planted in PVC pipes with 16 cm diameter and 60 cm length. After 3 months when plants were established. Drought stress was imposed in pots by lack of watering until each plant source was completely dried and turned yellow. This experiment was conducted in green house in a complete randomized factorial block design with 3 replications. During the experiment, leaf growth, color, plant density, leaf relative water content, electrolyte leakage and percent leaf firing were measured or evaluated in 6 days intervals. Leaf proline content was measured at 3 stages: the beginning of the experiment, in commencement of drought effects o foliage and just before complete leaf firing. Soil moisture was measured when 90% of foliage dried. Results indicated that relative water content was significantly reduced in stressed plants and when this value dropped below 60 percent leaf growth stopped in all plants. Reduction in leaf water content and leaf growth observed earlier in cool season grasses than in warm season grasses. Moisture stress in all plants reduced leaf color, plant density and increased electrolyte leakage and percent leaf firing. Only wheatgrass did not show significant increase in electrolyte leakage. Wheat grass, tifway and population number 88 were able to maintain their color and density longer than other grasses. Electrolyte leakage and percent leaf firing were also observed later than others in these grasses.
