Journal of Nematology (2004) 36, 153-159

Claudio M.G. Oliveira, Judith Hübschen, Derek J.F. Brown, Luiz C.C.B. Ferraz, Frank Wright and Roy Neilson (2004)
Phylogenetic relationships among Xiphinema and Xiphidorus nematode species from Brazil inferred from 18S rDNA sequences
Journal of Nematology 36 (2), 153-159
Abstract: Maximum likelihood trees produced from 18S rDNA sequences separated 14 Xiphinema and five Xiphidorus nematode species from Brazil into distinct groups that concurred with their current morphological taxonomic status. Species belonging to the X. americanum group (X. brevicolle, X. diffusum, X. oxycaudatum, and X. peruvianum) formed a, single group that was clearly separated from the other Xiphinema species. As with previous taxonomic studies that noted only minor morphological differences between putative X. americanum group species, separation of these species based upon 18S rDNA sequences was inconclusive. Thus it is probable that instead of comprising distinct species, the X. americanum group may in fact represent numerous morphotypes with large inter- and intra- population morphological variability that may be environmentally driven. Within the cluster representing non X. americanum group species, there was little statistical support to clearly separate species. However, three subgroups, comprising (i) the X. setariae/vulgare complex, (ii) X. ifacolum and X. paritaliae, and (iii) X. brasiliense and X. ensiculiferum were well resolved.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Full text of article
Database assignments for author(s): Claudio Marcelo G. Oliveira, Derek J.F. Brown, Roy Neilson

Research topic(s) for pests/diseases/weeds:
identification/taxonomy
molecular biology - genes

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Xiphinema (genus)
	Xiphinema americanum
	Xiphinema ensiculiferum