Chinese Bulletin of Botany ›› 2019, Vol. 54 ›› Issue (4): 455-463.DOI: 10.11983/CBB19044

Special Issue: 逆境生物学专辑 (2019年54卷2期)

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

Antifungal Activity and Mechanisms of Natamycin Against Colletotrichum gloeosporioides in Postharvest Mango Fruit

Jiayi Liu1,Jiaxin Wang1,Haichao Song2,Zhengke Zhang1,Xiangbin Xu1,Xuncong Ji3,*(),Xuequn Shi1,*()   

  1. 1 College of Food Science and Technology, Hainan University, Haikou 570228, China
    2 Institute of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
    3 Institute of Plant Protection, Hainan Academy of Agricultural Sciences, Haikou 571100, China
  • Received:2019-03-08 Accepted:2019-05-06 Online:2019-07-10 Published:2020-01-08
  • Contact: Xuncong Ji,Xuequn Shi

Abstract: In this study, we examined the inhibitory effects of natamycin at different concentrations on the conidial germination and mycelial growth of Colletotrichum gloeosporioides in vitro as well as the controlled effect of natamycin on postharvest anthracnose of mango (Mangifera indica) fruit inoculated with C. gloeosporioides. To further explore the underlying antifungal mechanism, we analyzed the membrane permeability, soluble protein content, changes in cell membrane integrity, intracellular reactive oxygen species (ROS) level and mitochondrial distribution in C. gloeosporioides after natamycin treatment. Natamycin at 3 mg∙L -1 effectively suppressed the conidial germination, germ tube elongation and mycelial growth of C. gloeosporioides. Also, 80 mg∙L -1natamycin significantly inhibited the expansion of anthracnose lesions in mango fruit during storage. Furthermore, natamycin treatment increased the relative permeability and soluble protein content in the cell membrane of C. gloeosporioides. After 8h treatment with natamycin 2 mg∙L -1, the staining rate of damaged cell membranes in C. gloeosporioides was 33.6% and 13.9% in the control. The staining rate of intracellular ROS reached 46.9% in treated conidia, which was 39.7% higher than that of the control. Natamycin treatment caused heterogeneous distribution of intracellular mitochondria along with weaker fluorescence as compared with the control. In summary, natamycin can destroy the cell membrane of C. gloeosporioides, induce ROS accumulation and reduce mitochondrial activity, thus interfering in the normal physiological activity of C. gloeosporioides and affecting its metabolic activities.

Key words: natamycin, mango, Colletotrichum gloeosporioides, antifungal mechanism