Effects of Water Salinity on Growth Indices and Physiological Parameters in Some Wild Pistachio

The effect of four water salinity levels (0.75, 5, 10 and 15 dS.m-1) on growth indices and physiological parameters in some wild pistachio (P. atlantica, P. atlantica subsp. kurdica, P. atlantica subsp. mutica and P. atlantica subsp. cabulica) were investigated under greenhouse conditions. Leaf dry weight was reduced to about 30-54% at ECw 10 dS.m-1. Chemical analysis of shoot and root indicated that the concentration and distribution of Na+, K+ and Ca2+ in pistachio rootstocks were affected by salinity. The concentrations of Na+ and K+ increased in shoot with a rise in water salinity level. Comparison between Na+ concentration of shoot and root showed that all rootstocks limited the Na+ transportation to shoot tissue up-to 15 dS m -1, and retained it in the roots. However, this ability was weaker in Kurdica rootstock. Leaf area was affected by salinity, expect in Atlantica. The maximum of leaf area and chlorophyll index were observed in Atlantica rootstock. In Atlantica, leaf area and chlorophyll index were decreased 15.76% and 12.56% at 15 dS. m-1 compare to control respectively, whereas those were 19.95% and 19.08% in Mutica. Relative water content of leaves (RWC) was decreased in all rootstocks at solution 4 (15 dS. m-1). The rootstocks were differed considering to stomata resistance of leaves response to salinity, so that; it was gradually increased in Atlantica and Cabulica rootstocks, while those were non-consistent in Kurdica and Mutica. Based on measured parameters Atlantica and Kurdica could be considered as tolerant and sensitive pistachio rootstocks to water salinity, respectively.