Molecular Phylogeny of Cytospora Species Associated with Canker Diseases of Apple Trees in Turkiye

Cytospora spp. is a cause of canker and dieback disease in many plant species, including apple trees worldwide, and causes significant crop losses worldwide. In this study, samples of Cytospora were collected from symptomatic branches in apple trees in the Egirdir district of Isparta province, Turkiye. Cytospora isolates identification were determined by internal transcribed spacer (ITS), ef1-alpha (translation elongation factor 1-alpha) and large subunit (LSU) sequence analysis. In molecular analyses, the species isolated from apple trees were identified as Cytospora parasitica and C. sorbicola. nrITS sequence lengths between 456 and 655 base pairs, ef1-alpha sequence lengths between 538 and 647 base pairs and nrLSU sequence lengths between 1015 and 1314 base pairs were determined. In addition, pi = nucleotide diversity, 0.021220 for ITS sequence, pi = 0.021220, for ef1-alpha sequence pi = 0.085317 and for LSU sequence pi = 0.009499 were determined. Also, in phylogenetic trees constructed using ITS, ef1-alpha and LSU sequences C. parasitica and C. sorbicola species appeared in separate branches. As a result, nrITS, ef1-alpha and nrLSU sequences were efficient in the identification and phylogenetic analysis of Cytospora species. Cytospora sorbicola is recorded as being associated with apple canker disease in Turkiye for the first time.