24-Epibrassinolide supplemented with silicon enhances the photosynthetic efficiency of Brassica juncea under salt stress

Silicon (Si) and 24-Epibrassinolide (EBL) were exogenously applied to assess the photosynthetic efficiency in Brassica juncea under salt stress and to correlate it with the antioxidant system. Seeds of B. juncea were sown in pots and supplemented with NaCl at 15-day stage. Si and EBL treatments were given at 20 and 25-day stage, respectively. Net photosynthetic rate and stomatal conductance reduced significantly in the presence of NaCl. The spray of Si and EBL alone or in combination significantly increased the growth and photosynthetic traits in the presence/absence of NaCl stress. The antioxidant activity (catalase, peroxidase and superoxide dismutase) and proline content got enhanced by salt stress which was further enhanced upon follow-up treatment with 24-epibrassinolide and silicon alone or in combination. A combined effect of Si and EBL counters the damaged caused by the salt stress.