Metabolic activities in some rice varieties under submergence stress

Rice varieties showed significant reduction in grain yield when exposed to submergence at different water depth during post flowering stages. The soluble nitrogen, free amino acid, proline was recorded higher in leaves under submergence than those of non submerged plants. The phenol content, phosphatase and catalase activities showed concomitant increase with depth of submergence. Except the free amino acid content during post flowering stages, other biochemical parameters had hardly any influence on the grain yield.