Exogenously applied selenium (Se) mitigates the impact of salt stress in Setaria italica L. and Panicum miliaceum L.

Abstract

This study is about mitigation of salt stress in Setaria italica L. and Panicum miliaceum L. by selenium (Se) which is a micronutrient beneficial for plant growth and development, but its role in combating salt stress in millets has not been evaluated. The objective of this study was to investigate the effect of exogenously applied selenium (Se) on the biochemical stress indicators in both the crops grown under different salt treatments (50 mM–200 mM NaCl). The results indicated that salinity increase the antioxidant enzyme activities viz., superoxide dismutase, catalase, ascorbate peroxidase, glutathione-S-transferase, guaiacol peroxidase and glutathione reductase, which were amplified in both the genotypes by Se application. The effect on antioxidative enzymes was more prominent in case of S. italica L. Furthermore, salt stress-triggered hydrogen peroxide (H2O2) production and Se supplementation lowers it down. The osmolyte concentrations (total soluble sugar, proline, glutathione and glycine betaine) increased under salinity however they were further increased upon Se treatment. The results suggest that there is a Se-mediated alleviation of salt stress in millets (S. italica L. and P. miliaceum L.) which is mostly related to stimulation of the plant’s antioxidative defence system.