Stress Measurements of Solanum melongena L. and Celosia argentea L. plants exposed to SO 2 and NO 2 gases separately in Chambers

Abstract

Stress induces protection responses from exposed plants. Celosia argentea L. and Solanum melongena L. plants were separately exposed to NO 2 and SO 2 gases in chambers and their morphological appearance and
biochemical responses were measured. Parameters analysed were morphological appearance, chlorophyll content, superoxide dismutase, catalase activity, peroxidase activity, proline and ascorbic acid contents. Three weeks and four weeks old C. argenta and S. melongena were separately exposed to NO 2 and SO 2 gases. After exposure, the morphological changes recorded for test plants (C. argentea and S. melongena) exposed to gas treatments were severe bleaching of leaves, dehydration, discolouration and wilting. Chlorophyll content analysis of leaves showed a significant reduction (p< 0.05) for test plants in both 3 weeks and 4 weeks old plants. Chlorophyll contents of C. argentea and S. melongena plants showed similar pattern where values for control plants were significantly higher than test plants (p< 0.05) under both NO 2 and SO 2 gases. Biochemical analysis for SOD, catalase, peroxidase and ascorbic acid contents showed the same pattern where values for control plants were higher than values for test plants (p< 0.05). Proline contents of leaves were significantly higher in test plants than in unexposed plants under NO 2 and SO 2 gases. The increase in proline contents by test plants is insufficient to give protection and survival to C. argentea and S. melongena exposed to NO 2 and SO 2 gases.