TOLERANCE OF RICE TO NICKEL IN NUTRIENT SOLUTION

For screening tolerance of six cultivars of rice (Oryza sativa) to dif ferent concentrations of nickel (0, 6, 12, 18, 24 and 30 mu g dm(3)), growth parameters (root and shoot length, root and shoot dry matter pr oduction) and root and shoot tolerance indexes were tested after 7, 10 and 13 d of treatment. In presence of nickel in nutrient solution, ro ot growth of cv. Nilgiri was enhanced, while in cvs. Subhadra, Khandag iri, Rudra, Sankar and Annapurna it decreased. The root tolerance inde x (RTI) and shoot tolerance index (STI) in cv. Nilgiri were high; cvs. Sankar and Khandagiri, however, showed a low RTI. Based on the standa rd growth parameters, six cultivars of rice were ranked in respect of their tolerance to nickel: Nilgiri > Annapurna > Subhadra > Khandagiri > Rudra > Sankar.