The functions of an apple cytosolic malate dehydrogenase gene in growth and tolerance to cold and salt stresses

► MdcyMDH expression is positively correlated with growth vigour of plant and cell. ► MdcyMDH was sensitive to abiotic stresses. ► MdcyMDH overexpression promotes apple callus and tomato plant growth. ► MdcyMDH overexpression enhances cold and salt tolerance of plant and cell.