Abstract: An extended foliar greenness even under post-anthesis drought can be simply called as the stay-green phenotype. The maintenance of a balance between nitrogen (N) demand and supply during grain filling stage is the key to stay-green phenotype. Chlorophyll catabolic enzymes (CCEs) are responsible for the degradation of chlorophyll. When a mutant disrupts the activity of these CCEs, it leads to stay-green phenotype. There are five classes of stay-green identified as A, B, C, D and E. The genotype possessing these traits can retain more photosynthetically active leaves under water shortages at the grain filling stage. Maintaining the greenness of leaves for longer time is the fundamental strategy for increasing crop yield and market value. Understanding the physiological and genetic basis of stay-green in relation to drought-resistance mechanisms are fundamental to the development of new strains that are better adapted to dry conditions.