02213nas a2200193   4500008004100000245017000041210006900211260007600280300001200356490000700368520140300375100001801778700001601796700002201812700001801834700001501852700001501867856013701882       2009                        eng d00aSmall Subunit rDNA-Based Phylogeny of the Tylenchida Sheds Light on Relationships Among Some High-Impact Plant-Parasitic Nematodes and the Evolution of Plant Feeding0 aSmall Subunit rDNABased Phylogeny of the Tylenchida Sheds Light   a3340 PILOT KNOB ROAD, ST PAUL, MN 55121 USAbAMER PHYTOPATHOLOGICAL SOC  a227-2350 v993 aCyst (Heteroderidae), root knot (Meloidogyne spp.), and lesion (Pratylenchus spp.) nematodes all belong to a single nematode order, Tylenchida. However, the relationships between and within these economically highly relevant groups, and their relatedness to other parasitic Tylenchida is unclear. We constructed a phylogeny of 116 Tylenchida taxa based on full length small subunit ribosomal DNA (small subunit [SSU] rDNA) sequences. Ancestral state reconstruction points at a gradual development of simple to more complex forms of plant parasitism. Good resolution was observed in distal clades that include cyst, root knot, and lesion nematodes, and monophyly of most families was confirmed. Our data suggest that root knot nematodes have evolved from an ancestral member of the genus Pratylenchus, but it remains unclear which species is closest to this branching point. Contrary to the notoriously polyphagous distal representatives, basal members of the genus Meloidogyne (and probably, their common ancestor) have narrow host ranges. Our analysis also shows that mitotic parthenogeny has arisen at least two times independently among root knot nematodes. In many cases resolution till species was observed, suggesting that SSU rDNA sequences have a potential for DNA barcode-based species identification with, due to the overall conserved nature of this gene, limited intra-species variation.1 aHolterman, M.1 aKarssen, G.1 avan den Elsen, S.1 avan Megen, H.1 aBakker, J.1 aHelder, J.  uhttps://nematoda.myspecies.info/content/small-subunit-rdna-based-phylogeny-tylenchida-sheds-light-relationships-among-some-high-impa00569nas a2200169   4500008004100000245006900041210006600110300001400176490000700190100001900197700001400216700001900230700001600249700001300265700002000278856010100298       2002                        eng d00aPhylogenetic analyses of \emph{Meloidogyne} small subunit r{DNA}0 aPhylogenetic analyses of emph Meloidogyne small subunit r DNA  a319–3270 v341 aDe Ley, I., T.1 aDe Ley, P1 aVierstraete, A1 aKarssen, G.1 aMoens, M1 aVanfleteren, J.  uhttps://nematoda.myspecies.info/content/phylogenetic-analyses-emphmeloidogyne-small-subunit-rdna