Abstract: In order to investigate the influence and difference of shallow and deep wounds on healing ability of potato tubers，the cultivar‘Qingshu 168’was used as material in this study. The epidermal tissues were removed from the tubers with stainless steel blade，with a square of 2 cm，0.3–0.5 mm depth（shallow wounded）and 3.0–3.2 mm depth（deep wounded）. The wounded tubers were healed at ambient temperature（20–25 ℃，relative humidity 70%–80%）in darkness. The influence of shallow and deep wounds on healing effects were compared by weight loss rate and incidence，the changes of the lignin and suberin poly aliphatic（SPA）deposition，the activity of key enzyme and the contents of metabolites of phenylpropanoid pathway. The results showed that no significant difference was observed in weight loss rate between shallow and deep wounded tubers，however，the incidence of shallow wounded tubers was significantly（P < 0.05）lower than the deep wounded，with only a half of the deep-wounded after 14 days of healing. The shallow wounded tubers accumulated more lignin and suberin than the deep wounded during healing. The thickness of lignified cell layers of shallow wounded tubers were 107.5% higher than that of the deep wounded after 14 days of healing. Moreover，a higher phenylalnine ammonialyase（PAL）activity was observed in the shallow wounded tubers during healing，with 34.3% higher than that in the deep wounded after 5 h of healing. Meanwhile，the shallow wounded tubers deposited more lignin and total phenolic during the first 7 days of healing，the content of lignin and total phenolic were 24.8% and 12.1% higher than that in the deep wounded after 5 days of healing. Although a significant difference was observed in flavonoids content between shallow and deep wounded tubers at early stage of healing，there was no obvious difference at mid and late stage of healing. The correlation analysis demonstrated that the incidence of tubers negatively correlated with the thickness of lignified cell layers and lignin content. PAL activity positively correlated with the thickness of lignified cell layers，total phenolic and flavonoids. It is suggested that the shallow wounded tubers possess better healing ability and more phenylpropanoid metabolic activities.

Key words: potato, tuber, wound, wound healing, phenylpropanoid metabolism