During the summers of 2013-2014, symptoms similar to viscid rot and upright disease were observed on cranberries (Vaccinium macrocarpon) on one plantation in central Poland. The associated fungi were isolated from symptomatic plant tissue. On the basis of morphological and cultural characteristics and the ability of isolated fungi to elicit viscid rot symptoms on cranberry fruits, they were classified as the genus Diaporthe. Further analysis of ITS sequence data allowed for the classification of the newly obtained isolates as D. vaccinii. Additional analysis of genetic diversity using five RAPD and eight ISSR primers constituted additional confirmation of genetic distance existing between closely related D. vaccinii and D. eres species, enabling their differentiation.

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Based on partial sequence analysis of the b-tubulin gene, 19 isolates of fungi causing bull's eye rot on apple in Poland were classified into species: Neofabraea alba, N. perennans and N. kienholzii. To the authors' knowledge, the detection of N. kienholzii is the second in Europe and the first in Poland. Species affiliation of these fungi was confirmed by a new species-specific multiplex PCR assay developed on the basis of previously published methods. The new protocol allowed for the specific identification of bull's eye rot-causing species, both from pure cultures and directly from the skin of diseased or apparently healthy apples. In 550 samples of diseased fruits collected from nine cold storage rooms located in three regions of Poland, in 2011 and 2012, N. alba was detected as the predominant species causing bull's eye rot, occurring on average in 94% of the tested samples. Neofabraea perennans was found in a minority of apple samples, N. kienholzii was found only in two apple samples, while N. malicorticis was not detected in any sample tested. In tests on 120 apparently healthy fruits, only N. perennans was detected in a single sample. The results of genetic diversity analyses of bull's eye rot-causing fungi based on the b-tubulin gene sequence and an ISSR (inter-simple sequence repeat) PCR assay with two primers were consistent, showing the expected segregation of tested isolates with respect to their species boundaries. However, the genetic distance between N. perennans and N. malicorticis was very low, as reported previously.

For the years 2012–2018, we investigated the occurrence of storage diseases caused by fungi on four cultivars of apples grown in the central part of Poland. The fruits were picked in orchards managed with Integrated Pest Management (IPM) practices and stored in a cold room for 5–7 months. Depending on the season, apple cultivar and localization of orchard, the incidence of diseases was different. On apple cvs “Gala”, “Ligol” and “Golden Delicious”, bull’s eye rot (Neofabraea spp.) was the most frequently observed disease, whereas on apple cv. “Gloster”, gray mold (Botrytis cinerea) predominated. The blue mold (Penicillium expansum), brown rot (Monilinia spp.) and fungi of Alternaria spp. occurred at significantly lower intensity. We detected the occurrence of the new storage diseases of apples caused by Colletotrichum spp., Neonectria ditissima and Diaporthe eres.

B��� H., D��� B., S���������� P. (2004): Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum. Plant Protect. Sci., 40: 128-134.The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48-76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present -the hyphal tips were swollen and ball-shaped sporelike structures aggregated in chains were formed.