Potassium status of the rice shoot as an index for salt tolerance

Eleven varieties of rice showing tendency of high K accumulation were tested for sodicity tolerance at four levels. Kala Rata 1–24 and Vytilla were the most sensitive and failed to reach maturity at pH 10.0. CSR-1 and H3–14 were the most tolerant types which showed least reduction in shoot dry weight and grain yield. Sodicity resulted in marked imbalance in the Na, K content and Na/K ratio of shoot in all the genotypes. Although these changes were relatively more pronounced in sensitive rice varieties, nevertheless none of the parameters was adequate to explain differential sodicity tolerance of these cultivars.