Zhang, X., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
Zong, Y., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
Li, Z., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
Yang, R., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
Li, Z., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
Bi, Y., College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China;
 

Pichia guilliermondii is a yeast widely found on soil, leaves and fruit surfaces and is known to have a good biocontrol effect on a variety of postharvest diseases of fruits and vegetables. In this study, artificially wounded apple fruits (cv. Fuji) were treated with P. guilliermondii. It was found that P. guilliermondii growth increased rapidly at wound sites of fruit in the early stage of healing and later decreased rapidly. The yeast significantly reduced weight loss of wounded fruit and the disease index of inoculated fruit with Penicillium expansum. On the 5 d of healing, the weight loss and disease index of treated fruits were 25 % and 44 % lower than the control, respectively. P. guilliermondii also promoted the accumulation of O2 ·− and H2O2, increased the activity of superoxide dismutase, catalase, peroxidase and polyphenol oxidase in fruit wounds. Furthermore, P. guilliermondii activated phenylalnine ammonialyase activity and increased the content of total phenols, flavonoids and lignin in the fruit wounds. It is suggested that postharvest P. guilliermondii treatment could promote the wound-healing of apple fruit by activating the reactive oxygen species and phenylpropane metabolism in the fruit wound.