The effect of exogenous DIM on Brassica napus and its role in response to heavy metal stress

Abstract

Brassica napus is a plant that is used for human and animal consumption. This plant is also used for phytoremediation due to its relatively higher level of heavy metal tolerance. In South Africa, mining is one of the main drivers of the economy. One of the major negative environmental impacts of mining is heavy metal contamination. Soil metal content can rise to levels that are quite high and can even have a negative impact on the yields of B. napus crop. The glucosinolate-myrosinase system of B. napus is a system that is used as defence against biotic stressors. Indole glucosinolate breakdown products have been proven to enhance the antioxidant capacity of plants. Some have also shown growth promoting properties in plants. We studied the effect of exogenous DIM on B. napus and it role in Zr induced heavy metal stress. Germination percentages revealed that DIM increased germination, Zr application decreased germination and the DIMZr treatment reversed the negative impact of Zr application on B. napus. The effect of treatments on the biomass of B. napus was assessed by determining the dry weights. Results show that exogenous DIM improves biomass. Zr application decreased biomass and DIM-Zr treatment ameliorated the effect of Zr application.