Effect Of1-MCP,MeSA,H₂O₂on Cold Injury Of Deastringented Persimmon Fruit During Cold Storage

Considering the need of production and business, part of permission needs to be deastringented before cold storage. However, deastringented persimmon fruit during cold storage is sensitive to chilling injury. In order to maintain deastringented persimmon fruit storage quality and reduce chilling injury, we take Diospyros Kaki L.f cv. Fangshi as a testing material, studied the effect of1-MCP,H2O2,MeSA and1-MCP combined H2O2, MeSA on the deastringented persimmon storage quality. Besides, we study the mechanism on how MeSA reduce chilling injury in deastringented permission treated with1-MCP. The results showed that:1.1-MCP treatment can efficiently inhibit the decline of firmness of deastringented persimmon fruit during cold storage, retain the delcine of soluble solids content(SSC), postpone the appearance of respiration and ethylene, and reduce areas of respiration and ethylene production peak.1-MCP did not affect relative conductivity nor chilling injury symptoms. But it contributes to the appear of chilling injury.2. MeSA treatment can inhibit the decline of firmness of deastringented persimmon fruit and retain the delcine of SSC. It can reduce relative conductivity and chilling injury. Among them,0.1mmol/L MeSA is most effectively.0.01,0.1and0.5mmol/L MeSA have no effect on respiration and ethylene production.3.0.01,0.1and1mmol H2O2treatment have no effect on firmness,SSC,respiration rate and ethylene production rate. Among them,1mmol/L H2O2can postpone appearing time of chilling injury, and have no effect on chilling injury index.4.1-MCP combined different concentrations of H2O2treatment have no obvious effect on firmness,SS,respiration rate,ethylene production rate,color and relative conductivity.1-MCP combine H2O2treatment reduce the chilling injury for the only two weeks prior to cold storage, but aggravate symptoms of chilling injury for the last four weeks.5.1-MCP combined different concentrations of MeSA treatments both effective in delaying the decline of firmness of deastringented persimmon fruit and inhibiting the development of chilling injury. After three weeks storage, compared with control,chilling injury index can be reduced by75%. Among them,1-MCP combined0.1mmol/L MeSA treatment is most effective. 6.1-MCP combined0.1mmol/LMeSA treatment increased SOD and POD activity, and inhibited PPO activity and O2′-release rate.1-MCP combined0.1mmol/LMeSA treatment can also inhibit LOX activity, reduce membrane lipid peroxidation(Delayed the increase in unsaturated fatty acids in the fruit cell degradation and saturated fatty acid content), reduce the accumulation of MDA and the relative permeability of membrane, thereby maintaining the integrity of the cell membrance structure and function. This may be e the mechanism on how0.1mmol/L MeSA reduce chilling injury in deastringency permission treated with1-MCP.