Selecting High-Performance Rootstocks for Pistachio Cultivars under Salinity Stress Based on Their Morpho-physiological Characteristics

In Iran, the most pistachio orchards are located in semi-arid regions and irrigated with saline water which influences their growth and yield. The present investigation was conducted to evaluate the effects of salinity on growth, and morpho-physiological parameters of six pistachio genotypes as rootstock ('Akbari & apos;, 'Ahmad-Aghai & apos;, 'UCB-1 & apos;, 'Italyayi & apos;, 'Ghazvini & apos; and 'Badami & apos;). Treatments were different salinity concentrations using NaCl at 0.5, 12 and 18 dSm-1 on six genotypes of pistachio. According to the results, by increasing salinity, the FW, DW, number of growing leaves, SPAD index of leaves, chlorophyll content and stomatal conductance were reduced, but electrolyte leakage of leaf and root tissues, soluble sugars and antioxidant capacity were increased. 'UCB-1 & apos;, 'Akbari & apos; and 'Ahmad-Aghai & apos; had the highest leaf area compared to other genotypes under salinity conditions. The lowest leaf abscission was belonged to 'UCB-1 & apos; and its difference was significant with other genotypes. The WUE of 'UCB-1 & apos; reduced and it was higher than 'Akbari & apos;. The growth of 'UCB-1 & apos; significantly declined up to 79.6% under salinity stress. Salinity stress had the lowest adverse effect on the growth of 'Akbari & apos; and 'Ahmad-Aghai & apos; genotypes. There was no significant difference among genotypes in regard to RWC under salinity stress. It can be concluded that 'UCB-1 & apos;, 'Akbari & apos; and to some extent 'Ahmad-Aghai & apos; were tolerant to salinity stress and can be recommended to use as rootstock under moderate salinity conditions.