The genus Ditylenchus Filipjev, 1936, consists of more than 80 nematode species and contains mostly mycophagous species, but also plant parasites. The most economically important are Ditylenchus dipsaci (Kühn, 1857) Filipiev, 1936, and Ditylenchus destructor Thorne, 1945. Ditylenchus destructor infests more than 100 host plant species, selleck products including Solanum tuberosum, and occurs worldwide, mostly in temperate regions. Ditylenchus dipsaci is also present worldwide in areas that have a moderate climate and

infects more than 500 species of host plants (Caubel and Pedron 1976). Ditylenchus dipsaci is characterized by extensive intraspecific variations. At least 30 host races (with limited host ranges) of this pest can be distinguished (Sturhan and Brzeski 1991). These variations led some (e.g. Sturhan and Brzeski 1991; Palmer et al. 1992; Subbotin et al. 2005) to consider the D. dipsaci species as a ‘species complex’. This complex has been subdivided into two groups. The first contains diploid populations characterized by their so-called ‘normal size’ and named ‘D. dipsaci sensu stricto’. This group comprises most of the populations recorded so far. The second group of polyploids is further grouped into

the following clades: Ditylenchus spp. B (the so-called giant race from Vicia faba) that was recently singled out as the new species Ditylenchus gigas (Vovlas et al. 2011); Ditylenchus this website sp. C, which is now described as Ditylenchus weischeri (Chizhov et al. 2010); and Ditylenchus sp. D, E and F associated with plant species of the Fabaceae, Asteraceae or Plantaginaceae. Vicia faba is the host in which both types of races, those belonging to D. dipsaci and to D. gigas, can be found. The above information is further confirmed by phylogenetic data (e.g. Subbotin et al. 2005). Both D. dipsaci and D. destructor significantly adversely affect the quality and the quantity of plants. These two nematode

species cause swelling, distortions, stunting as well as necrosis and rotting of plant parts. For this reason, D. dipsaci and D. destructor are under quarantine regulations in the European and Mediterranean Plant Protection Organisation (EPPO) region. Ditylenchus gigas is a serious pest of V. faba. Its presence was reported in several European and African countries bordering Nintedanib (BIBF 1120) the Mediterranean Sea. Our aim was to characterize and subsequently to study the phylogeny of some nematode populations found in Poland, specifically 11 D. dipsaci populations from three different hosts, three D. destructor populations from S. tubersosum ssp. tuberosum and one D. gigas population from V. faba ssp. minor. The sequences were compared with each other and with other populations of these species available in the GenBank database. Phylogenetic analysis showed that in the case of D. dipsaci, even populations isolated from the same host may be clustered separately. On the other hand, most of D. destructor populations isolated from the S.