Effect of salinity on potassium, calcium and magnesium content in rice varieties

Twelve genotypes of paddy were tested under pot culture for their salinity tolerance at 10 and 15 dSm⁻¹. Salt tolerant genotypes, viz. Kalaratta, Damodar and RPA-5929 have relatively lower Na/K, Na/Ca and Na/Mg ratio, as compared to salt sensitive genotypes which have medium to high ratios in the leaves. At 15 dsm⁻¹ salinity, Na/K, Na/Ca and Na/Mg ratio ranges from 0.75 to 0.82, 5.94 to 7.17 and 0.74 to 0.99, respectively in tolerant, whereas in moderately tolerant the ratio ranged from 0.97 to 1.49; 7.63 to 10.10 and 0.91 to 1.56, respectively and 0.98 to 1.53; 9.35 to 12.98 and 1.01 to 1.40, respectively in sensitive genotypes.