Solution culture for screening rice varieties for sodicity tolerance

Abstract

Sodic soils are widespread, especially in the Indo–Gangetic plain. Amelioration with gypsum is effective, especially when combined with growing a crop of rice. However, it has proved difficult to generate new varieties of sodic-tolerant rice, because of the difficulties of screening – other than in the field, where spatial variation of sodicity is notoriously high. Growing plants at high pH in solution culture in a controlled environment is problematic, because of the effects of pH on nutrient availability. This study evaluated a system of growing rice in a nutrient solution with added Tris but without minor nutrients, which were supplied in a foliar spray. Performance was evaluated from the change in weight and in appearance and correlated with performance in soil. Growing rice in the presence of Tris (4 mM, pH 8·6) provides a means of evaluating genotypic differences in response to sodicity.