The current status of Phytophthora ramorum in Austria

摘要

Since the middle of the 1990s, symptoms of wilting in plants of Rhododendron and Viburnum were quite often observed in tree nurseries of Germany and the Netherlands. At approximately the same time a new fatal phenomenon in several oak species, named sudden oak death, was recorded in the USA. In 2001 this new pathogen was described as Phytophthora ramorum. Since 2002, monitoring has been carried out in the member states of the European Union. At first this new Phytophthora species was found mainly onRhododendron (except R. simsii) and Viburnum, but now many hosts are known, including Arbutus sp., Camellia japonica, Hamameils virginiana, Kalmia latifolia, Leucothoe sp., Pieris formosa var. forrestii, P. japonica, Syringa vulgaris and Taxus baccata. In 2004, even trees such as Aesculus hippocstanum, Castanea sativa, Fagus sylvatica, Quercus cerris, Q. ilex and Q. falcata were infected. In the 2004 monitoring programme, 447 visual inspections in tree nurseries, garden centres and in the public green were carried out in Austria. In all federal states, samples were taken from forests and windbreaks in which susceptible trees such as Aesculus hippocstanum, Castanea sativa, Fagus sylvatica, Pseudotsuga menziesii, Quercus cerris, Q. petraea, Q. robur, Q.rubra and Taxus baccata were present. However, none of the examined plants was infected by Phytophthora ramorum.