Morphological and molecular characterization of Neoscytalidium novaehollandiae, the cause of Quercus brantii dieback in Iran

Abstract

During the period from 2013 to 2015 a tree health survey was conducted in Persian oak (Quercus brantii Lindl.) forests throughout Kermanshah province in Western Iran. Oak trees showing dieback of branches and stems were sampled, and fungal colonies resembling those of Neoscytalidium sp. were obtained from diseased tissues. Based on morphology and phylogeny of DNA sequence data for the internal transcribed spacer (ITS) rDNA, nuclear ribosomal large subunit (LSU) and translation elongation factor 1-alpha (TEF 1α) gene regions, all isolates were identified as Neoscytalidium novaehollandiae. Pathogenicity tests were carried out on 2-year-old, potted Q. brantii plants and on detached branches under partially controlled conditions. Pathogenicity tests showed that all the isolates were able to infect, and cause disease symptoms on, inoculated branches and plants. This is the first report of N. novaehollandiae as the causal agent of Q. brantii dieback.