The pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its pathogenicity to German Pinus sylvestris provenances

The pine wood nematode, Bursaphelenchus xylophilus, can cause pine wilt disease on susceptible conifer species, mainly Pinus spp., outside its natural range. One of the management options for pine wilt disease in recent decades in affected countries such as Japan was the evaluation of potentially tolerant or resistant host species. In the framework of Pest Risk Assessment and Management as well in Contingency Planning in Germany, we studied the pathogenicity of B. xylophilus towards different German pine provenances. According to the German Legal Ordinance on Regions of Provenance, 2-to 3-year-old Pinus sylvestris saplings of eight provenances were artificially inoculated with B. xylophilus using a suspension of 4000 B. xylophilus in 300 mu l of tap water per tree. No significant differences in tree death between the provenances were detected. All inoculated provenances reached a mortality of 100 %, but significant differences occurred in the time course of disease development.