Effect of foliar-applied Si in alleviating cadmium toxicity to different Raya (Brassica Junceae L.) genotypes

Purpose Heavy metal toxicity poses severe threats to soil and crop productivity. Cadmium (Cd) toxicity disrupts plant metabolism, reducing growth and yield. Si has emerged as a potential element in the context of metal toxicity, playing a crucial role in the compartmentalization and immobilization of metal ions. This study explores the potential of foliar-applied Si to mitigate Cd toxicity in Raya ( Brassica juncea L.). Methods Seedlings underwent Cd toxicity induction using CdCl 2 (300 μM) along with control (0 μM) and were subjected to foliar Si application of Na 2 SiO 3 (0 and 500 ppm). The impact on agronomic parameters, photosynthetic pigments, antioxidants (SOD, POD, CAT), and stress markers (H 2 O 2 , MDA, proline) was evaluated. Results Cd stress reduced agronomic parameters, while Si application, particularly in Super Raya, showed positive effects under stress and non-stress conditions. Photosynthetic pigments decreased in response to Cd stress, although Si had a significant effect. Biochemical attributes such as antioxidants (SOD, POD, and CAT) and stress markers (H 2 O 2 , MDA, and proline) increased, with positive effects shown in the Cd+Si treatment. Conclusion This study unveils the potential of foliar-applied Si to alleviate Cd-induced toxicity in Raya, offering novel insights into its impact on agronomic and physico-chemical attributes. Si application emerges as an effective strategy to limit Cd uptake in aerial parts of the plant, paving the way for future research in optimizing Si application for enhanced plant resilience to heavy metal stress.