New blight of Cupressaceae in Austria and Croatia. : Poster presented at Meeting of IUFRO Working Party 7.02.02 Foliage, shoot and stem diseases Hungary, 21 – 27 May 2007
Arborvitae (Thuja spp.) and False cypresses (Chamaecyparis spp.) are common plant species used for hedges in gardens, parks and urban green in Europe. In 2003, blight was reported from several large trees of Chamaecyparis lawsoniana growing in an Austrian park. In May 2003, samples were taken and a mitosporic fungus fruiting abundantly on dead leaves and twigs was identified as Stigmina thujina (Dearn.)Sutton. In order to estimate seasonal changes in spore production samples were taken monthly during 2004 and conidiomata were counted. In addition, mycelial growth of Stigmina thujina on malt agar at different temperatures was assessed in 2004. In 2006, similar Symptoms were recorded on a few 25-35 year old Chamaecyparis lawsoniana in a nursery near the town Delnice in Western Croatia. Site factors of the two diseased stands are compared and predispositions discussed.
