The Root-Knot Nematode Producing Galls on Spartina alterniflora Belongs to the Genus Meloidogyne: Rejection of Hypsoperine and Spartonema spp.
Root-knot nematodes are a major group of plant-parasitic nematodes, but their sister group within the Tylenchida remains to be identified. To find the sister group and for any investigation of the evolutionary biology of the genus Meloidogyne, it would be useful to identify the most basal species within Meloidogyninae. Meloidogyne spartinae, a root-knot nematode parasitic on cordgrass (Spartina spp.), constitutes a potentially interesting early diverging (or at least highly divergent) root-knot nematode because it was originally described in a different genus, Hypsoperine (and later Spartonema), due to its unique anatomy and biology (although it was later put in synonymy by some, but not all, taxonomists). We have sequenced the whole 18S rDNA of this species and compared it to other sequences of this region that are available in GenBank for numerous Meloidogyne species. Phylogenetic analysis unambiguously locates the branch corresponding to M. spartinae as a lately diverging species, more closely related to M. maritima, M. duytsi or the M. ardenensis-hapla group. Thus, the distinction of a separate genus (Hypsoperine or Spartonema) for this species is not justified.
Plantard
Olivier
O
Equipe "Biologie et Génétique des nématodes phytoparasites", INRA Agrocampus Rennes, UMR 1099, Biologie des Organismes et des Populations appliquée à la Protection des Plantes (BiO3P), Domaine de la Motte, BP 35327, 35653 Le Rheu Cedex, France Current address: INRA, ENVN, UMR 1034 IHPM, F-44307 Nantes cedex 03 Georgian Court University, Department of Biology, 900 Lakewood Ave., Lake wood, NJ 08701-2697.
Valette
Sylvie
S
Gross
Michael F
MF