Effects of postharvest 1-MCP and calcium treatments on the quality and skin browning spot incidence of Huangguan pear fruit.

Treatments of 1000 nL·L-1 1-MCP fumigation(1-MCP),4% CaCl2 dip(Ca)and the combination of 1-MCP and Ca(1-MCP + Ca)were applied to harvested Huangguan pear fruits.The results showed that compared with control(without 1-MCP or Ca treatment),treatments of Ca,1-MCP and 1-MCP + Ca maintained the higher firmness,titratable acid(TA)and chlorophyll contents,reduced the skin browning spot index,had slight effect on contents of total soluble solid(TSS)and vitamin C of fruits,also decreased peak value of ethylene production rate more or less,reduced soluble polyphenol content and polyphenoloxidase(PPO)activity markedly,and suppressed the rise of cell membrane permeability and H2O2 content of peel.But it had no obvious effect on the respiratory rate of fruits.Treatments of Ca and 1-MCP+Ca significantly increased Ca content of peel and flesh of fruits.On the whole,1-MCP+Ca was the most effective way to keep fruit quality in all treatments.It indicated that inhibiting the production of the polyphenol substances and keeping integrity of cell membrane structure should be an important cause for 1-MCP and Ca treatments,mainly Ca,to reduce the browning spot of peel in Huangguan pear fruits significantly.