Exogenous glutathione enhances proline accumulation and cadmium (Cd) translocation in the leaves of in vitro Celosia argentea L.

Glutathione (GSH) is a tripeptide present in the nonenzymatic antioxidant system of plants. Celosia argentea L. is an ornamental species capable of efficiently absorbing cadmium (Cd). This study evaluated the effect of exogenous GSH on the development and Cd accumulation of in vitro C. argentea plants. The findings recorded in this study pertain to growth, biochemical and Cd accumulation parameters. Cd stress inhibited the growth of the shoots and roots of C. argentea. In non-stress conditions, exogenous GSH significantly enhanced root growth indices; however, Cd stress significantly alter root growth indices. At 2.5 mM GSH, the optimal concentration, root length grew by an average of 25 %, while average fresh and dry biomass increased threefold and twofold, respectively, compared to the control. Under Cd stress conditions, exogenous GSH slightly improved leaf pigmentation in C. argentea. Simultaneously, the proline content, which helps plants respond to stress, reached over 0.86 µmol/g across all 3 concentrations (1, 2.5 and 5 mM), while the Cd-stressed sample without GSH had 0.44 µmol/g. Adding 2.5 mM GSH to the growing medium greatly improved the translocation factor (TF-an important measure in phytoremediation) but did not change how much Cd the plants' leaves could accumulate. The results of this study revealed that GSH has a role in the physical and chemical processes of C. argentea leaves when they are under stress from Cd.