Effect Of NO Treatments On Cold Resistance Of Postharvest Xinmi No.3 Melon

Postharvest ‘Xinmi No.3’ melon is oval fruit. It has orange flesh, small seed cavity, tough skin,resistance to transport and more disease-resistant. However, the ‘Xinmi No.3’ melon production season concentrated in high temperature season, long distance transportation at room temperature, senescence and quality deterioration quickly and rot serious. Hypothermia could significantly delay the ‘Xinmi No.3’melon postharvest quality deterioration, but the temperature is too low will cause chilling injury, induce rot to the ‘Xinmi No.3’ melon Postharvest storage resulting in huge losses. Under cold stress environment, the‘Xinmi No.3’ melon prone to chilling injury, limiting the cryogenic storage technology in the ‘Xinmi No.3’melon during storage applications. Nitric oxide(NO) plays a role in signal transduction in plants in the process of lipid or water environments, NO as a signaling molecule involved in plant defense mechanisms,or as a compound having hormone properties affect the growth and development capabilities. Researching different concentrations of nitric oxide on the ‘Xinmi No.3’ melon chilling injury symptoms, respiratory metabolism, quality changes, active oxygen metabolism and osmotic adjustment substance at 1℃.1. At 1℃, 20μL/L NO treatment ‘Xinmi No.3’ melon can effectively alleviate chilling injury occurs,reduce respiration rate and release of ethylene, delay fruit firmness and soluble solids decreased, slow titratable acidity and Vc content decreased, reduce chilling injury symptoms and prolong postharvest the‘Xinmi No.3’ melon storage period. 60μL/L NO treatment ‘Xinmi No.3’ melon will increase the chilling injury symptoms, ethylene emission, the respiratory rate, boosting the ‘Xinmi No.3’ melon quality deterioration.2. At 1℃, 20μL/L NO treatment ‘Xinmi No.3’ melon can effectively alleviate superoxide dismutase(SOD), catalase(CAT), peroxidase(POD) decreased activity, inhibition the content of hydrogen peroxide(H2O2) and superoxide anion(O2-?) increase. 60μL/L NO treatment ‘Xinmi No.3’ melon make SOD, CAT,POD activity decreased, at the same time, increase the content of H2O2 and O2-?.3. At 1℃, 20μL/L NO treatment ‘Xinmi No.3’ melon can decrease the content of cell membrane permeability and MDA, increase the content of osmotic adjustment, reduce cold stress on cell membrane structure damage. 60μL/L NO process treatment ‘Xinmi No.3’ melon will increase the cell membrane permeability and MDA content, reduced the content of osmotic adjustment, increased the cell membrane structure damage.