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

Abstract

Heavy metals constitute significant environmental stressors, capable of impeding growth and triggering the production of reactive oxygen species. This study investigates the impact of two heavy metals, cadmium and copper sulfate, on the germination and seedling growth of two canola cultivars. The experiment employs a factorial design based on a completely randomized setup with three replications. Treatments involve cadmium and copper sulfate concentrations of 0, 10, 20, and 30 ml/l, alongside two canola cultivars (Hyola 50 and Homolious). Each petri dish contains 25 seeds, and various treatments, including a distilled water control, are applied. Seed germination percentages are recorded daily at specific intervals, and growth rates are assessed by measuring radicle length, plumule length, and seedling length on the final day of the experiment. Results indicate that different levels of cadmium do not significantly affect germination and seedling growth. In contrast, various concentrations of copper sulfate exert a significant impact on plumule length (PL), radicle length (RL), seedling length (SL), and seed vigor index (SVI) at a 1% significance level. As copper concentration increases, PL, RL, SL, and SVI decrease. Both canola cultivars exhibit significant differences in all measured germination indices at the 1% level, with Hayola 50 demonstrating superior performance and higher values than Homolious for all traits except daily germination speed. Interaction effects between all treatments do not significantly influence any of the traits examined. Therefore, it is recommended to consider Hyola 50 as a suitable plant for phytoremediation due to its superior germination characteristics.