Study of some morphological characteristics in three turf grass species under drought stress conditions

Restriction of water resources is one of the main challenges in turf management and the most important tool in reducing of the water requirement in turf land is using drought resistant species. This study was carried out to evaluate some morphological responses of Agropyrondesertorum, Poapratensiscv. Barimpala and Bromusinermis subjected to withholding irrigation. Turf grass seeds were cultured in cylindrical pots in outdoor conditions. Plants were irrigated daily until drainage occurred. After establishment of plants, irrigation was withheld until leaf wilting of the most plants reached to 80%, and then re-watered. After irrigation withholding, leaf wilting of B. inermis, P. pratensis and A. desertorum reached to 80% respectively. Leaf wilting of A. desertorum and P. pratensis decreased during re-watering and finally became similar to control plants; whereas B. inermis was completely wilted. Height growth and shoot dry matters were decreased due to drought stress, that this decrease in A. desertorum was less than two other species. Turf quality under drought conditions declined but decreased quality in A. desertorumoccurred later. Results of root characteristics shown that A. desertorum had higher root length and root dry weight than other species. B. inermis, P. pratensis had not significant difference in two traits. Root length in control plants significantly was higher than plants under drought stress. In A. desertorum and P. pratensis root to shoot ratio in grass subjected to drought stress was higher than control grass while the root to shoot ratio in B. inermis did not show significant difference between these treatments.