Phylogeny of Bursaphelenchus species derived from analysis of ribosomal internal transcribed spacer DNA sequences

Bursaphelenchus species can cause serious economic damage to pine forestry, and are widely distributed across the globe. The genetic structure of the B, mucronatus-B. xylophilus species group was investigated using sequences of the internal transcribed spacers of the ribosomal RNA gene repeat as a m arker. Analysis of the ITS from 11 Bursaphelenchus isolates, using Aphelenc hoides rhytium as an outgroup, supports the perception that the two species are distinct genetic entities. Significant divergence was however found wi thin each species. ITS sequence analysis does not support a separation of E uropean and Japanese B, macronatus into distinct species-level taxa.