Cookies Policy

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here

Diversity and phylogenetic relationships within the spiral nematodes of Helicotylenchus Steiner, 1945 (Tylenchida: Hoplolaimidae) as inferred from analysis of the D2-D3 expansion segments of 28S rRNA gene sequences

No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this article

+ Tax (if applicable)
Add to Favorites
You must be logged in to use this functionality

For more content, see Nematologica.

The spiral nematodes of the genus Helicotylenchus are globally distributed and associated with the root system of diverse groups of plants in cultivated and uncultivated areas. Several species are considered serious parasites of crops. The identification of many Helicotylenchus species is not always reliable, in part because many species share very similar diagnostic characters and high intraspecific variation. To verify species identification of geographically distant populations of Helicotylenchus, we tested monophyly of some classical morphospecies and studied their phylogenetic relationships; specifically, we conducted sequence and phylogenetic analysis of 89 sequences of the D2-D3 expansion segments of 28S rRNA gene sequences from 54 Helicotylenchus isolates, including species identified as H. brevis, H. digonicus, H. dihystera, H. labiodiscinus, H. leiocephalus, H. martini, H. multicinctus, H. platyurus, H. pseudorobustus and H. vulgaris, together with three outgroup taxa. Phylogenetic analysis distinguished nine highly or moderately supported major clades within Helicotylenchus. Using the molecular approach we were able to confirm congruence with morphologicalbased identification of samples of H. dihystera and H. multicinctus. However, sequence and phylogenetic analysis using Bayesian inference and maximum parsimony analysis showed that isolates collected in different countries and morphologically identified as H. pseudorobustus, H. digonicus or H. vulgaris were each representative of several different and, sometimes, unrelated lineages. Further detailed comparative morphometrics and morphological studies will help to elucidate if there is some misidentification or if putative species actually comprise a complex of cryptic species. Molecular analysis also revealed that 14 samples were classified as representatives of 11 unidentified species. Molecular characterisation of known Helicotylenchus species especially, using samples collected from type localities, is needed for future reliable identification of species of this genus.

Affiliations: 1: Plant Pest Diagnostic Center, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832-1448, USA, Centre of Parasitology of A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, Leninskii Prospect 33, Moscow, 117071, Russia;, Email:; 2: Florida Department of Agriculture and Consumer Services, DPI, Nematology Section, P.O. Box 147100, Gainesville, FL 32614-7100, USA; 3: National Collection of Nematodes, Biosystematics Programme, ARC-Plant Protection Research Institute, Private Bag X134, Queenswood, 0121 South Africa; 4: Department of Plant Pathology, University of Nebraska, Lincoln, NE 68583, USA; 5: Department of Nematology, University of California, Riverside, CA 92521, USA; 6: P.O. Box 1758, Palmerston North 4440, New Zealand


Full text loading...


Data & Media loading...

Article metrics loading...



Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Subscribe to ToC alert
  • Get permissions
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
    Nematology — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation