Identification and characterization ofNeofabraeafungi causing bull’s eye rot on apple in Poland

Abstract

Bull's eye rot is the most important storage disease of apples, causing up to 30-40% crop yield losses on susceptible cultivars in Poland. Due to the intensive plant material exchange, the knowledge about the species composition of causal agent of the disease needs to be updated. In this study, a previously modified multiplex PCR assay (Gariepy et al., 2003) was applied for the identification of the fungi in pure cultures. In years 2014-2015, 497 isolates of Neofabraea spp. from 493 samples of symptomatic fruit collected from 8 cold storages located in different regions of Poland were identified. Neofabraea alba was the predominant species (87% of the isolates) followed by N. perennans and N. kienholzii represented by 10 and 3% of the isolates, respectively. The species N. malicorticis was not detected. For the determination of genetic diversity, representative isolates of N. alba (25), N. perennans (22) and N. kienholzii (10) were analyzed by ISSR PCR with 5 microsatellite markers. The resulting dendrogram comprising results of all five ISSR reactions, segregated all strains according to their species affiliation. No relations were found between the observed amplification pattern and the geographical origin of the strain.