كليدواژه :
Anthocyanine , Carotenoids , Phytoremediation , DPPH activity
چكيده فارسي :
Chromium imposed harmful morphological, physiological, and metabolic effects in plants. This study was aimed to evaluate the impact of citric acid (0, 2.5 and 5 mM), on different morphological and physiological characteristics of garden cress exposed to chromium-VI stress (0, 1, and 10 mM). Results showed that shoot and root length, fresh and dry weight, chlorophyll, carotenoids, and DPPH activity decreased under chromium, while anthocyanin increased. Also, at high chromium concentrations, the rate of accumulation of this metal in the shoot parts declined but increased in the roots. This study showed that the addition of citric acid (2.5, and 5 mM) with chromium (10 mM) significantly enhanced shoot and root length, fresh and dry weight, chlorophyll, carotenoids while a similar increase was observed in the combination of 1 mM chromium and 2.5 mM citric acid, 5 mM citric acid in combination with 1 mM chromium reduced shoot and root length, fresh and dry weight, chlorophyll and carotenoids. The addition of 2.5 and 5 mM citric acid along with chromium 1 and 10 mM significantly decreased Anthocyanin content. Besides, citric acid 2.5 and 5 mM alleviated the adverse effect of chromium 1 and 10 mM on DPPH activity. This means that the transfer from the root to the shoot will increase under the effect of citric acid at high chromium concentrations but in low concentrations of chromium, citric acid reduced the concentration of chromium in the shoot parts considering the chromium uptake and translocation factor results, garden cress is not suitable for phytoremediation. Hence, the citric acid played this role through the regulation of the antioxidant system to diminish the toxicity of chromium.
