A Study of Morphological, Physiological and Biochemical Responses of Poa pratensis L. (Kentucky bluegrass) cv. Barimpala to Drought Stress Conditions

Drought stress is one of the phenomena that adversely affects growth and quality of plants، with turfgrass being no exception. For a study of the responses of Poa pratensis L. cv. ’Barimpala‘ to time periods of drought stress، turfgrass seeds were cultivated at 60cm depths in cylindrical pots of 15cm diameters and placed outdoors. Plants were daily irrigated to the point until drainage occurred. Following the establishment of the plants irrigation was withheld until leaf wilting occurred in most plants to a level of 80% when they were rewatered. All the traits were assessed within 5d intervals throughout the experiment. Drought stress declined shoot growth، shoot height، grass quality and chlorophyll content، while electrolyte leakage، leaf wilting and proline contents being increased with prolonged stress. Leaf wilting decreased during rewatering and at 11d was similar to control plants. In stress conditions، RWC decreased after 5d past. Oxidative injury was induced due to increase in lipid peroxidation. Drought stress had no effect on height and dry weight of roots. Activities of Catalase (CAT)، Ascorbate Peroxidase (APX) and Peroxidase (POD) were not significantly different from control plants up to 5d past then began to increase at 10d.