New country and regional records of the pine needle blight pathogens Lecanosticta acicola, Dothistroma septosporum and Dothistroma pini

Abstract

SummaryDothistroma needle blight (DNB), caused by Dothistroma septosporum and Dothistroma pini, and brown spot needle blight (BSNB), caused by Lecanosticta acicola, are some of the most serious and damaging foliar diseases of pines (Pinus spp.). Lecanosticta acicola is reported for the first time from Ireland and Portugal and confirmed from the Black Sea coast of Russia (Krasnodar region, Sochi). It has also been recovered from the first, and only, reported site in Latvia 4 years after efforts to eradicate it were undertaken. Dothistroma septosporum is reported for the first time from Ireland on Pinus sylvestris and Pinus radiata. It was also found in Comunitat Valenciana, Spain, and confirmed as the causal agent of the disease in Bulgaria. Dothistroma pini was found in Aragon, Spain, and in Arkansas, USA, where it was found on Pinus elliottii, a new host for this pathogen. A new ITS haplotype of D. septosporum is reported from the Bulgarian isolates and a new ITS haplotype of D. pini from the Arkansas isolates. These new country and regional reports extend the geographical and host range of these pathogenic fungi and continue a trend seen since the 1990s. Of particular concern are the geographically widespread new reports of L. acicola from the most north‐ and south‐westerly (Ireland and Portugal) to the most south‐easterly (Russia) regions in Europe, suggesting that not only is this pathogen continuing to spread in Europe but also is well adapted to a wide range of climatic conditions.