Hydrogen Sulphide: A Key Player in Plant Development and Stress Resilience

ABSTRACT Based on the research conducted so far, hydrogen sulphide (H 2 S) plays a crucial role in the development and stress resilience of plants. H 2 S, which acts as a signalling molecule, responds to different stresses such as heavy metals, drought, and salinity, and it regulates various aspects of plant growth and development including seed germination, root development, stomatal movement, flowering, and fruit ripening. Additionally, H 2 S is involved in mediating legume‐Rhizobium symbiosis signalling. It modulates plant responses to external environmental stimuli by interacting with other signalling molecules like phytohormones, nitric oxide, and reactive oxygen species. Furthermore, H 2 S exerts these regulations since it can modify protein functions through a reversible thiol‐based oxidative posttranslational modification called persulfidation, particularly in stress response and developmental processes. As a result, H 2 S is recognised as an important emerging signalling molecule with multiple roles in plants. Research in this field holds promise for engineering stress tolerance in crops and may lead to potential biotechnological applications in agriculture and environmental management.