In 2002 a fungus causing powdery mildew on Rhododendron in Latvia was discovered and identified as Erysiphe azaleae. The powdery mildew has since then been observed on leaves and seed pods of deciduous azaleas as well as evergreen rhododendrons, although the disease is more common on taxa of deciduous azaleas. Development of mature chasmothecia has been noticed at every location where the disease was detected. The distribution area of E. azaleae is expanding gradually from the south-west and central regions to the north and east parts of Latvia. It has been suggested, that climate change and large-scale plant import favour this process. To our knowledge, Latvia is so far the farthest north-easternmost site where E. azaleae has been detected.
Apine I., Bankina B., Nikolajeva V., Tomsone S. (2013): Powdery mildew on Rhododendron caused by Erysiphe azaleae in Latvia. – Czech Mycology 65(1): 113–123.
