Effect of Cadmium Toxicity on Aquatic Macrophyte Pistia Stratiotes (L.)
The present study focuses on cadmium toxicity on morphology and selected biochemical parameters of Pistia. The laboratory experiments were conducted for the assessment of morphological index parameters (MIP), biochemical parameters and accumulation of cadmium in plants at its various concentrations (0.1, 0.5, 1.0, 1.5 and 2.0 ppm) at the regular interval for 12 days exposure. Pistia showed visible symptoms like withering of roots, chlorosis and necrosis at higher concentration (2.0 ppm), however, the plant showed normal growth at lower concentration (0.1 ppm). The estimation of biochemical parameters (Total chlorophyll, Protein and Carbohydrate) of test plants showed a significant increase at lower concentration (0.1 ppm) of cadmium. The biochemical parameters decrease with increase in exposure concentration and duration. The toxic effect of cadmium is directly proportional to its concentration and duration. The accumulation of cadmium by Pistia stratiotes was maximum at 4 days exposure duration and marginal at subsequent concentrations and exposure duration. With respect to biochemical parameters the concentrations are significant. However, metal accumulation is significant at concentrations and exposure duration.