Physiological and molecular mechanisms of response to drought stress in alfalfa

Alfalfa (Medicago sativa) is a major forage crops throughout the world, and of great nutritional, economic, and ecological value. It is mainly cultivated in the northwestern and northeastern regions of China, where water is the main limiting factor influencing plant yield. In this study, we quantified changes in photosynthesis, respiration, antioxidant activity, osmoregulation, and abscisic acid levels under drought stress, and proposed the mechanisms of physiological response to drought stress in alfalfa. The response process involving transcription factors, protease genes, and drought-resistance genes under drought stress was investigated as well. In conclusion, our study emphasized the importance of response to drought stress in alfalfa from a new perspective.