The growth and yield of many crops that are crucial to agriculture have been negatively impacted by the challenges that arise from a number of known and unknown abiotic and biotic stresses imposed on by population growth, global warming, and other possible climatic causes. Stay-green (SG) is a secondary characteristic that helps crop plants, particularly in drought and heat stress situations, to retain their green leaves and ability to perform photosynthesis for a longer period of time after anthesis. As a result, SG plants yield more than non-SG plants due to their prolonged grain-filling period. Crop yields have increased as a result of functional SG breeding, especially when paired with other beneficial features. To overcome the production stagnation linked to environmental stress adaptation, it may be necessary to understand the molecular and physiological mechanisms underlying the SG characteristic.