Cotton Salt Stress Resilience: Integrating Physiological, Molecular, and Agronomic Strategies for Next-Generation Breeding

Soil salinity is a major challenge for plant growth, triggering a two-phase stress response: an immediate osmotic phase followed by a longer-term ionic phase. Plants sense and respond to salt stress through intricate signalling networks involving ion channels, calcium signalling, and membrane-bound sensors, which activate the downstream signalling networks, including SOS pathway, MAPK signalling cascades, ROS signalling, and hormone-mediated responses. Collectively, these signalling pathways maintain ionic balance and support stress adaptation through transcriptionally regulated expression of salt-responsive genes. Cotton (Gossypium spp.), an important global crop, is moderately salt-tolerant but still suffers considerable yield losses under saline conditions, particularly in arid and semi-arid regions. This review highlights the physiological and molecular responses of cotton to salinity stress, focusing on recent progress in functional genomics and molecular genetics in cotton. Finally, we discuss that the integration of improved agronomic practices with advanced molecular strategies can strengthen cotton's salt tolerance and ensure sustainable production in salt-affected areas.