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main objective of this study was to determine the drought resistance potential of Stipa
barbata, Agropyron cristatum and Agropyron desertomm.
The study was carried out in the greenhouse at Karadj Natural Resources Faculty of Tehran University. The experilnent was based on a completely randomized design of three Plant species, three irrigation periods and four replications.
Morphological and physiological characteristics such as amount of wilting, leaf water potential, shoot and root weight and root/shoot ratio were measured in the first phase of the study. Anatomical changes of leaf such as epiderm, paranchima, and stomata condition were also assessed carefully. Besides, the amount of species soluble carbohydrate was _easured.
. Overall results indicated that the highest amount of wilting belonged to Stipa barbata. In terms of leaf water potential, there was no significant difference between the three species under study.
Shoot weight and total weight of all three species decreased with increasing water stresses
during the study period, while root weight and root /shoot ratio increased greately.
Agropyron desertorum and Ag. crista turn showed the same morphological and physiological
characteristics while Stipa barbata was quite different from the above mentioned two species.
Leaf anatomical changes indicated that Ag. crista turn and Ag. desertomrn are of high
adaptation potential for drought resistance.
Soluble carbohydrate increased with increasing stresses during the study period, but
differences between the three species were not highly significant.