The involvement of phenolic metabolism in superficial scald development in ‘Wujiuxiang’ pear

  • Shuo Zhou
  • Yunxiao Feng
  • Zhe Zhao
  • Yudou Cheng
  • Junfeng Guan


Superficial scald often occurs after a long term of cold storage in apples and pears. In this study, the superficial scald index, the contents of major phenolic compounds, polyphenol oxidase (PPO) activity and its related genes expression in peel was investigated during cold storage period and at shelf life in ‘Wujiuxiang’ pear (Pyrus communis L. cv. Wujiuxiang) with or without 1-MCP treatment. It showed that arbutin, chlorogenic acid, catechin and epi-catechin were the main phenolic compounds in the peel, and 1-MCP treatment significantly inhibited scald development while altering the composition of phenolic compounds, inhibited PPO activity and the expression of phenylalanine ammonia ligase (PAL1, PAL2), cinnamate 4-hydroxylase (C4H1, C4H2) and PPO (PPO1, PPO5) and up-regulated the expression of hydroxycinnamoyl-CoA shikimate/quinate hydroycinnamoyltransferase (HCT1), p-coumarate-3-hydro-xylase (C3H) and PPO (PPO4 and PPO6) in the peel. These results suggested that the phenolic metabolism is closely related to the scald development, and several genes related to phenolic metabolism were involved in scald development.