Research Progress on Effect and Mechanism of NO Delaying Ripening and Senescence and Improving Resistance of Fresh Fruits and Vegetables

As an important signal molecule, nitric oxide(NO) plays an important role in regulating postharvest physio-biochemical reaction and quality of fruit and vegetables. This article summarizes the effect of NO on delaying ripening, reducing chilling injury, and enhancing disease resistance of postharvest fruit and vegetables. NO delays the ripening and senescence by inhibiting the biosynthesis of ethylene, and enhances cold resistance by activating the antioxidant system, maintaining energy levels, protecting cell membranes and regulating the CBF cold response pathway. The mechanism of enhancing disease resistance is to kill pathogens, to regulate secondary metabolic processes, and to improve the gene expression of disease-related proteins and disease resistance genes. In addition, the future research for postharvest NO treatment on the basis and application of fruit and vegetables is proposed.