Morph-Physiological Changes of Two Cultivars of Pomegranate  Rabab and  Shisheh Gap under Water Stress Conditions

Water is one of the major limiting factors for agricultural crops in arid and semiarid regions of the world. Iran is one of the largest producers and exporters of pomegranate in the world. In this research, the effect of water stress on some morphological and physiological responses of one year old saplings of two pomegranate cultivars, ‘Rabab’ and ‘Shishehgap’ was investigated. A factorial experiment was conducted in a complete randomized design with 4 replications and two plants in each replicate. Treatments were 4 levels of irrigations of 100, 75, 50 and 25% field capacity and two cultivars. The results showed that in both cultivars, with increasing drought, growth indices such as leaves number, shoot length, chlorophyll content and relative water content (RWC) decreased but the amount of proline and ion leakage increased. In this regard, ‘Rabab’ with more proline accumulation and less ion leakage as well as maintenance of RWC in comparison to ‘Shishehgap’ showed more tolerance to water stress and better its growth performance.