Variations in ribosomal DNA sequences and phylogeny of Globodera parasitising solanaceous plants

The D3 expansion region of the 28S gene and the ITS1-5.8S-ITS2 region of rD NA sequences from Globodera rostochiensis, G. pallida, G. tabacum tabacum, G. tabacum virginiae and G. tabacum solanacearum have been aligned and comp ared, There are no nucleotide differences in the D3 region sequences betwee n G. rostochiensis and G, pallida. Sequence analysis and RFLPs of ITS-PCR p roducts showed that several haplotypes are present in the genomes of G. ros tochiensis and G. pallida populations. Restriction patterns of PCR products for eight enzymes for differentiation of these two species are given. Phyl ogenetic analysis of 41 ITS region sequences obtained from populations and species of the subfamily Punctoderinae revealed four distinct main clades w ithin Globodera parasitising solanaceous plants: G. rostochiensis, G. tabac um, G. pallida and an undescribed Globodera sp. from South America. The uti lity of RFLP profiles and sequences of the rDNA are discussed for diagnosti cs and phylogeny of Globodera.