Role of proline in regulating turfgrass tolerance to abiotic stress

Turfgrasses used on golf courses, sports fields and in urban landscapes have significant ecological and economic values. Various abiotic stresses are crucial in limiting the growth and development of turfgrass. As an important amino acid metabolite, proline can act as a signal to trigger plant responses to stress. Proline accumulation is not only a stress signal, but also alleviates plant damage by maintaining photosynthesis and the activities of antioxidant enzymes and the levels of non-enzymatic antioxidant compounds, thus reducing reactive oxygen species content, and regulating osmosis. A better understanding of mechanisms of proline response to abiotic stress in turfgrass is vital for the development of stress-tolerant germplasm. This review summarizes research progress into the role of proline in regulating growth and physiological and molecular adaptations to abiotic stress, with emphasis on drought, salt and temperature tolerance.