Characterization of the Italian population of Ciborinia camelliae

Ciborinia camelliae Kohn is the causal agent of camellia flower blight. The fungus infects only the flowers of camellias causing serious damage to the plant, particularly from an aesthetic point of view. The disease has been reported in almost all countries where camellia is grown for ornamental purposes, but there are not many studies on the variability of the population of this phytopathogen. The main objective of this study was to contribute to study the level of variability within the Italian population. More than 130 C. camelliae strains were collected from six localities distributed in five Italian regions and identified also based on molecular characterization of the ITS nucleotide sequences. The population variability was assessed by comparing the morphological characters. From a phenological point of view, 11 different colony morphotypes were identified, whose presence/absence and frequency are different in the various locations considered. The study of the taxonomically valid nucleotide sequences to differentiate fungi at the species level confirmed that the strains under study belong to a single species. To further investigate Italian population of C. camelliae we sequenced by a combination of long and short reads technologies the genome of a representative strain. This genome represents a worldwide reference for future C. cameliae diversity and pathogenicity studies