Drought stress tolerance in rice: advances in physiology and genetics research

Plants are subjected to various abiotic stresses, of which drought can be considered as a major one, negatively affecting the productivity of rice every year. Rice is a staple food crop and plays a pivotal role in the diet of mankind. Drought avoidance and tolerance mechanisms are adopted by plant system. Expression of drought responsive genes, consequent biosynthesis of metabolites may occur under such stress conditions and help the plant to cope with the circumstances. Though the cellular genetic and metabolic mechanism of drought tolerance in rice were studied since long time, still there are complex traits whose mechanism should be clearly unraveled. This review is an attempt to connect the dots of research advances in physiology and genetics of rice, addressing the causes of drought and its impact on plant growth, with an emphasis on biochemical mechanisms mediated by phytohormones and molecular changes, such as expression of drought responsive genes and transcription factors were discussed along with the recent advances in the genome editing technology to develop drought tolerant rice varieties.