Hydrogen sulfide counteract copper induced inhibition of photosynthetic performance through altered proline metabolism and enhanced antioxidants in Cucumis sativus

Abstract

It has been recently discovered that hydrogen sulfide (H2S) is a gaseous substance responsible for controlling the growth and metabolism of plants. The present study was designed to explore the ameliorative effect of H2S on Cucumis sativus plants under increasing levels of copper. This study revealed that varying concentrations of H2S improved seed germination in a concentration-dependent manner. Furthermore, exogenous application of H2S to copper stressed plants accelerated photosynthetic performance, antioxidant system, proline accumulation, and maintained copper uptake that was reflected in improved growth parameters. In addition to this, H2S also curbed oxidative stress by lowering lipid peroxidation, H2O2 content, and electrolyte leakage. H2S enhanced activities of the antioxidant system, and proline metabolism leading to decontamination of cucumber plants under lethal dose of copper. This work offers an understanding that exogenously sourced H2S could be engaged as a significant biochemical approach in alleviating copper-induced toxicity in cucumber plants.

Keywords

• Antioxidant enzymes
• Copper stress
• Hydrogen sulfide
• Proline metabolism