First report of Plenodomus tracheiphilus in Canada and first report on elm
Plenodomus tracheiphilus (EPPO A2 list) is known as the causal agent of mal secco of citrus trees in EPPO region. This fungus was recently isolated from wilting elms (Ulmus sp.) in the province of Alberta in Canada. This is the first report of P. tracheiphilus on elms anywhere in the world, and the first report of P. tracheiphilus in Canada.
The identity of the fungus was confirmed by morphological analysis and sequencing. Pathogenicity tests were conducted on elm trees to fulfil Koch’s postulates. The fungus had been initially confused with Dothiorella ulmi. It is considered that the introduction of P. tracheiphilus in Canada is quite recent as regular monitoring has been conducted for Dutch elm disease (caused by Ophiostoma ulmi and Ophiostoma novo-ulmi) and symptoms of wilting were only observed after 2016.
The situation of Plenodomus tracheiphilus in Canada can be described as: Present, not widely distributed.
Sources
Yang Y, Fu H, Zahr K, Xue S, Calpas J, Demilliano K, Harding MW, Feindel D, Feng J (2024) Plenodomus tracheiphilus, but not Dothiorella ulmi, causes wilt disease on elm trees in Alberta, Canada. European Journal of Plant Pathology 169(2), 409-420. |