Changes in respiration, its allied enzymes, pigment composition, chlorophyllase and hill reaction activity of horsegram seedlings under salt stress

The effect af NaCl or Na₂SO₄ (100 meq/l) on respiration and its allied enzymes, the levels of free titrable acids, chlorophylls, chlorophyllase and the Hill reaction activity in horsegram seedlings was studied. Aldolase, isocitrate dehydrogenase (ICDH), succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) were found to increase considerably in shoots and roots of stressed seedlings. Except aldolase, the ICDH, SDH and MDH activities were higher in roots than in shoots. The higher activities of these enzymes under salt stress were associated with increased respiration rate in roots than in shoots during 7th day. The free titrable acids were significantly increased by both salt treatments. Further, the pigment composition and Hill reaction activity in leaves was more in NaCl stressed seedlings. Chlorophyllase activity did not show much variation between control and stressed seedlings.