Abstract
Decrease in yield of crop may be related to the imbalance of essential plant nutrients within the plant which may be controlled by the composition in the rooting medium, therefore, some experiments were conducted to determine whether some appropriate external ratios of ions help to maintain the suitable internal ionic composition and thus improve rice growth in the saline conditions. Hence, different ratios were established in the saline substrate involving two rice lines, i.e. NIAB 6 (salt tolerant) and BG 402-4 (less salt tolerant). Results showed that higher Ca2 +:Na+ ratios in the external medium did help in improving the shoot and root growth as well as they reduced the Na+accumulation and improved K+:Na+ ratio and K+ selectivity in both lines. It is confirmed that an adequate amount of Ca2 +in proportion to Na+must be present in the system to improve and/or maintain better K+ selectivity (S K+Na+