Growth and Chemical Composition of Pistachio Seedling Rootstock in Response to Exogenous Polyamines under Salinity Stress

In order to evaluate responses of a pistachio seedling rootstock (Pistacia vera L. cv. Ghazvini) to NaCl induced salinity stress and potential protective role of exogenous spermine and spermidine on NaCl induced salinity stress, a greenhouse experiment was conducted during growing season of 2009. The NaCl treatments, involving 800, 1600, and 3200 mg NaCl per Kg of soil for 90 days, suppressed growth of the seedlings and induced accumulation of Na+ and Cl- in roots and shoots. Accumulation of Na+ and Cl- in shoots was higher than in roots. Our data also showed more accumulation of K+ in the shoot than in the roots under salinity stress. The ratio of K+/Na+ in compare with control was highly significant in the shoots of stressed plants. Exogenous polyamines (PAs) prevented the growth reduction induced by salinity stress and reduced transport of Na+ and Cl- from the root to shoot and increased translocation of K+ from the root to the shoot of pistachio seedlings. We concluded that ‘Ghazvini’ rootstock appear to be a valuable seedling rootstock with a level of salt tolerance about 1600 mg NaCl Kg-1 Soil. It also concluded that application of exogenous PAs may protect pistachio seedlings from salinity stress effects.