Germination and seedling growth of two canola (Brassica napus L.) cultivars under heavy metals

Heavy metals are one of the most important environmental stresses, which can lead to reduced growth and production of reactive oxygen. In this study, the effect of two heavy metals (cadmium and copper sulfate) on germination of two canola cultivars were considered. This experiment was conducted a factorial based on completely randomized design with three replications. Treatments included cadmium and copper sulfate at concentrations of 0, 10, 20 and 30 ml/l and two canola cultivars (Hayola 50 and Homolious). Each petri dish was contained 25 seeds and different treatments were applied. Distilled water was used for control treatment. Seed germination percentage was measured daily at a specific time and the growth rate was determined by measuring radicle length and plumule length at the last day of the experiment. The results showed the effect of different levels of cadmium on germination and seedling growth was not significant. Different levels of copper sulfate had a significant effect on plumule length (PL), radicle length (RL), seedling length (SL) and seed vigor index (SVI) at 1 % level, so that with increasing cupper concentration, PL, RL, SL and SVI decreased. On all measured germination indices, two canola cultivars were significant at 1% level, so that Hayola 50 was better and had higher than Homolious for all traits except daily germination speed. Interaction effects between all treatments did not have a significant on any of the traits. Therefore, it is recommended to use Hyola 50 as a suitable plant for phytoremediation with higher germination characteristics.