No abstract

Two rice (Oryza sativa L.) cultivars, Koshihikari and Pokkali, were grown in solution culture at three concentrations of NaCl or Na 2 SO 4 [0 (S0), 50 (S1), and 100 (S2) mmol dm -3 ] and three N contents [0.7 (N1), 7 (N2) and 14 (N3) mmol dm -3 ]. Salinity significantly decreased dry matter of both cultivars. Pokkali had better growth than Koshihikari under both saline and non-saline conditions. Applications of N enhanced development of shoot dry mass under S0 and S1 treatments up to N2. Under S2, N application had no effect on shoot dry mass of both cultivars. Root dry mass of both cultivars decreased with increasing N application at S1 and S2. Shoot and root NO 3 -N content in both rice cultivars increased with increasing N concentration in the nutrient solutions. The absorption of NO 3 -N was less in Koshihikari than Pokkali plants, and also was much less in Cl -than SO 4 2-salinity suggesting the antagonism between Cl -and NO 3 -. In addition a significant negative correlation between concentrations of NO 3 -N and Cl -in the shoots or roots was observed in both cultivars.Additional key words: Cl -, cumulative transpiration, NO 3 -N, Oryza sativa, SO 4 2-.