Effect of Amonium: Nitrate Ratio on Growth and Nitrogen Uptake and Potassium: Sodium Ratio in Two Olive Varieties in Saline Conditions

To study the effect of salinity and ammonium: nitrate ratio on growth of saplings of Zard and Arbiquina olive cultivars، an experiment was carried out in a greenhouse in Tarom field station in 2010- using factorial arrangement in completely randomized design with three repetitions. Four levels of salinity: 150، 100، 50، 0 mMl-1 NaCl and four solutions with different ammonium: nitrate ratio including: N0:14 meql-1 nitrate; N2:2 meql-1 ammonium + 12 meql-1 nitrate; N4:4 meql-1 ammonium + 10 meql-1 nitrate; N6:6 meql-1 Ammonium + 8 meql-1 nitrate، were used on one-year old olive saplings grown in perlite: sand (1:1) medium. Results showed that different levels of salinity had significant effect on reducing leaf area، dry matter، vegetative growth (plant height)، change in plant height and N content and K: Na ratio in the leaf as well as increasing the number of dropped leaves and Na uptake. Application of different nitrogen ratio showed that ammonium increased in nutrient solution with reducing current year growth parameters and increasing the K: Na ratio and N content in leaves reducing Na uptake and number of dropped leaves. Therefore، high concentrations of ammonium and salinity intensified negative effects of either treatments.