| In this paper, the optimum treating conditions (treating concentrations and treating durations) of 1-MethylcycIopropene (1-MCP) on peach fruit (Prunus persica L. cv. zhonghuashoutao) qualities was selected; Effects of 0.5 uL/L 1 -MCP on postharvest physiology, qualities and disease resistance of peach fruit (cv. jiubao) were investigated; Effects of 200 mg/L BTH and 500 mg/L PHC on postharvest disease-resistance and qualities of peach fruit (cv. jiubao) were studied. The mechanisms involved in increasing disease-resistance of peach fruit after 1-MCP, BTH and PHC treatment were also discussed. These results will provide the useful information on how to effectively delay the senescence of peach fruit after harvest, on how to control the postharvest disease of peach fruit without the pollution to the environment and harmfulness to human healthy, and also will reduce the use of chemical fungicide on horticultural crops.Peach fruit (cv. Zhonghuashoutao) was treated with different concentrations of 1-MCP (0, 0.1 uL/L, 0.5 uL/L, 1 uL/L) for 12 h, 24 h, 48 h respectively at 20 ±2 ℃ with a 85%-95% relative humidity (RH) after harvest before cold storage (2 ± 1℃). Decreases in Levels of fruit firmness and titratable acidity, and increases in levels of soluble pectin content were significantly reduced by treating the fruit with 0.1 uL/L ~ 1uL/L 1-MCP for 24 h before storage at 2℃, and the best effects of 1-MCP treating duration on peach fruit qualities was observed in fruit treated with luL/L 1-MCP for 24 h, the optimum dose of 1-MCP on controlling peach fruit senescence was 0.5 uL/L X 24 h.Peach fruit (cv: Jiubao) was treated with multiple application of 0.5 uL/L 1-MCP after harvest at 20±2 ℃ with a 85%-95% RH before storage (20 ± 1 ℃). Results showed that 1-MCP effectively inhibited the ethylene evolution and respiration rate, ethylene climactic peak was also delayed by 4 days, whereas, ethylene climactic peak was delayed by 2 days after 1-MCP single treatment; 0.5 uL/L 1-MCP delayed the loss of fruit firmness and TA (titratable acidity), suppressed the increase of soluble sugar (SSC) and pectin content (SPC); multiple application of 0.5 uL/L 1-MCP was more effective than single application of 0.5 uL/L 1-MCP on delaying fruit ripening and improving fruit qualities; 1-MCP effectively reduced the lesion area of peach fruit inoculated with spores of Penicillium expansion at concentration of 1 X 106 conidia per milliliter, decreased the disease incidence and inoculation incidence, increased the activities of PAL and POD and the levels of phenolic compounds and lignin in peach fruit, whereas 20 uL/L ethylene treatment aggravated the lesion area, and increased the disease incidence and inoculation incidence; 1-MCP effectively enhanced the levels of O2- and H2O2 in the first 6 days after inoculation, decreased the activities of SOD and APX, enhanced the activity of GR and the levels of AsA and GSH, whereas ethylene treatment had no effect on the levels of O2- and H2O2 of peach fruit. Ethylene treatment enhanced the activities of CAT, GR and APX, decreased the level of AsA content.BTH and PHC were studied after harvest for inducing disease-resistance of peach fruit (cv.Jiubao) inoculated with spore suspensions of Penicillium expansum (1.2x104 CFU/mL). The disease incidence/inoculation incidence and the lesion area were obviously reduced by the postharvest BTH and PHC treatment. BTH and PHC treatment increased the levels of phenolic compounds and lignin in peach fruit, enhanced the contents of chlorogenic acid caffeic acid ferulicacid coumaric acid> cinnamic acid and catechinic acid and the activities of PAL, PPO and POD; In the 2nd day after inoculation, BTH and PHC treatment effectively enhanced the levels of H2O2 and O2- espeaciilly the content of H2O2 in treated fruit was greatly higher than control fruit by 37.0% and 14.9%; BTH and PHC treatment delayed the decline of SOD, inhibited the increase of APX and CAT activities, enhanced the activities of POD and GR and the levels of AsA and GSH; induced t...
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