A Comparative Analysis of Physiological and Biochemical Responses to Low Doses of Cadmium in Two Important Varieties of Oryza sativa L. of Odisha, India

Cadmium (Cd) is a non-essential heavy metal as well as an important environmental pollutant, which have a significant impact on plant metabolic system. The current study aims at investigating the effect of cadmium on physiological and biochemical processes of rice plants (variety - Khandagiri, Tejaswini). The germination rate of Khandagiri was 87.78 % in 20 M, 24.44 % in 400 M and that of Tejaswini was 81.11 % in 20 M, 18.88 % in 400 M. The total chlorophyll content of Khandagiri and Tejaswini at 400 M was 201.01 g/g, 177.47 g/g respectively. Carotenoid content of Khandagiri and Tejaswini at 400 M was 113.44 g/g, 92.7 g/g respectively. Starch content for both Khandagiri and Tejaswini was found to be 13.28 g/g, 6.23 g/g respectively at 400 M. The total sugar content at 400 M was 2.99 g/g and 1.882 g/g for Khandagiri and Tejaswini respectively. The proline content increased upon exposure to 20 M to 400 M cadmium. The above result revealed that with increased Cd concentration in the medium showed decreased germination rate, photosynthetic activity, total sugar, starch, but there was an increase in the proline content at different time intervals (7-21 days).