Abstract
In organic apple cultivation in South Tyrol (Italy) the losses caused by epiphytic fungi have increased considerably in recent years. Affected are mainly late varieties, varieties that are only extensively treated against fungal diseases, and orchards in humid locations. The damage pattern on the fruit is shown by dark spots on the skin. They resemble sooty blotch and can also be wiped off. The spots are not always visible at harvest. However, in long-term storage, especially with high humidity, the spots rapidly increase, making it difficult for the market to accept them. Various fungi are isolated on the fruits, but it is not clear which fungi are responsible for the damage. At the Laimburg Research Centre (RCL), field trials with PPPs and with the rain cover (Keep in Touch®, antiacqua system) have been conducted since 2014. In addition, tests were carried out before and after storage with various preparations, with hot water and with brushes. Brushing after storage has proven to be the best method, but Gloeosporium infestation increases slightly due to brushing.