Effect of cadmium on photosynthetic pigments, sugars and malondealdehyde content in (Brassica napus L.)

Cadmium is a heavy metal that causes oxidative stress in plants. Cadmium is highly toxic to plants and animals. In this study toxic effect of CdCl2 on (Brassica napus L.cv. Fusia) was investigated. Plants were grown in vermiculite and irrigated with Long Ashton nutrient solution (pH =5.5) containing CdCl2 from (0 to 800 μM). Leaves and roots from 30-day–old plants were taken and used for determination of biochemical and morphological parameters. The maximum accumulation of cadmium occurred in roots followed by leaves. In leaves cadmium treatment significantly decreased fresh weight at 600 and 800 μM CdCl2 but leaves dry weight and leaf area decreased at 400, 600 and 800 μM CdCl2. In roots cadmium treatment significantly decreased fresh and dry weigh at 600 and 800 μM CdCl2. Cadmium significantly lowered total chlorophyll, chlorophyll a/b ratio and carotenoid content at 400, 600 and 800 μM CdCl2. Cadmium at 600 and 800 μM CdCl2 increased content of soluble reducing sugars and malondealdehyde in leaves and roots of treated plants.