Dothistroma pini and D. septosporum occur in Switzerland
In Switzerland, red band needle blight (disease associated with Dothistroma pini and D. septosporum) was recorded for the first time in 1989, but the species of Dothistroma involved could not be determined. Since then, only damage to pine trees (mainly Pinus mugo and P. nigra) planted in urban environments has been reported. In September 2012 and April 2013, several mature planted trees and naturally regenerated young trees of P. nigra presenting symptoms of red band needle blight were observed in a forest along the shore of Lake Walensee. Symptomatic needles were collected from the litter and from a P. nigra tree (2 m tall, naturally regenerated) and tested in the laboratory (isolation on growing media, comparison of ITS sequences, characterization of mating types). Results confirmed the presence of D. pini and of D. septosporum (EU Annexes) in symptomatic needles. Interestingly, D. pini and D. septosporum were found on the same tree but not on the same needles. This is the first time that the presence of D. pini is reported from Switzerland. It is also noted that although symptoms of red band needle blight have been repeatedly observed on the studied site over the last 20 years, disease level always remained low and no tree mortality was noted.
Queloz V, Wey T, Holdenrieder O (2014) First record of Dothistroma pini on Pinus nigra in Switzerland. Plant Disease 98(2), p 1744.