EFFECTS OF BORON AND SODIUM CHLORIDE CONCENTRATION ON GROWTH AND PERFORMANCE OF SOME YOUNG PISTACHIO ROOTSTOCK SEEDLINGS

Pistachio is one of the important economic horticultural crops in Iran. Iranian pistachio is well known in the world horticultural market, and for this reason producing high quality pistachio nuts with low production cost is an important task for the Iranian pistachio industry. It is obvious that rootstocks play an important role in the growth and performance in all of pistachio production areas. On the other hand, most of the area of pistachio culture in Iran is located in the arid and semi arid regions with saline conditions, low rainfall and high evaporation rates. These conditions lead to increases in the amount of soil salinity. Moreover, low quality of irrigation water increases the salinity of the soil in such regions. The research reported here was begun in the 2000 growing season at Tarbiat Modarres University (TMU). The aim was to explore and investigate the salinity effects of sodium chloride and excess boron on three pistachio (P. vera L.) rootstocks including Badami-e-Zarand, Sarakhsi and Ghazvini. Sodium chloride (0, 75, 150 and 225 mM NaCl) and boron (0, 20 and 40 mg.liter^-1) treatments were applied at three days intervals with irrigation water. Plants were destructively harvested after 30 and 60 days of exposure to the salinity (NaCl) and boron (B) treatments for growth parameter measurements. Salinity resulted in a reduction in whole plant biomass on all of the rootstocks, although the effect of treatments was affected by plant genotypes. In addition, reduction in plant growth was associated with reduction of plant height and root length. Different B applications did not affect growth or other measured parameters after two months exposure time.