Disease cycle and epidemiology (Gloeosporium)

All three fungi overwinter in the orchard on cankers (G. perennans), dead twigs, diseased bark, dead leaves or mummified fruit.

  • Cankers result from fungal spores invading wounds, frost cracks, etc, in trees.
  • During wet weather in the growing seasons spores (conidia) produced on fruiting bodies (acervuli) on the cankers and other inoculum sources, are splashed dispersed to infect fruit.
  • Fruit infection can occur at any time during the growing season from blossom to harvest, when the weather is wet and is mainly through lenticels.
  • G. album and G. perennans are favoured by cool humid weather, whereas Colletotrichum spp. are favoured by warmer temperatures.
  • Gloeosporium and Colletotrichum rots are rarely seen in the orchard and infections remain latent for some time and start to appear in store from December onwards.