First Report of the Spiral Nematode Helicotylenchus microlobus Infecting Soybean in North Dakota

Publications

Share / Export Citation / Email / Print / Text size:

Journal of Nematology

Society of Nematologists

Subject: Life Sciences

GET ALERTS DONATE

ISSN: 0022-300X
eISSN: 2640-396X

DESCRIPTION

3
Reader(s)
9
Visit(s)
0
Comment(s)
0
Share(s)

SEARCH WITHIN CONTENT

FIND ARTICLE

Volume / Issue / page

Related articles

VOLUME 49 , ISSUE 1 (March 2017) > List of articles

First Report of the Spiral Nematode Helicotylenchus microlobus Infecting Soybean in North Dakota

GUIPING YAN * / ADDISON PLAISANCE / DANQIONG HUANG / ZAFAR A. HANDOO

Keywords : first detection, Helicotylenchus microlobus, identification, North Dakota, soybean.

Citation Information : Journal of Nematology. VOLUME 49 , ISSUE 1 , ISSN (Online) 2640-396X, DOI: 10.21307/jofnem-2017-039, March 2017

License : (CC BY 4.0)

Received Date : 22-December-2016 / Published Online: 21-July-2017

ARTICLE

ABSTRACT

Spiral nematodes (Helicotylenchus spp.) are common plant-parasitic nematodes in fields of many crops. In June 2015, two
soil samples were collected from a soybean field in Richland County, ND. Nematodes were extracted from soil using the sugar centrifugal flotation method ( Jenkins, 1964). Plant-parasitic nematodes were identified to genus based on morphological features and counted. Both samples contained spiral nematodes from 1,500 to 3,300 per kilogram of soil. In June and August 2016, 10 soil samples were collected from the same field. Nematodes were extracted, and nine of the samples had spiral nematodes ranging from 125 to 3,065 per kilogram of soil. One soil sample with 1,500 spiral nematodes per kilogram was used to inoculate two soybean cultivars Sheyenne and Barnes each in four replicates. After 15 wk of growth at 228C in a greenhouse room, the population of spiral nematodes was found to have increased greatly. The final density was 9,300 6 1,701 spiral nematodes per kilogram of soil for Sheyenne and 9,45162,751 for Barnes. The reproductive factor in Sheyenne and Barnes was 6.2 and 6.3, respectively, indicating that this spiral nematode infects and reproduces well on these two soybean cultivars. Infected soybean roots had small brown lesions on the surface. Individual spiral nematodes were handpicked and examined morphologically and molecularly for species identification. Morphological measurements of adult females (n = 15) included body length (mean = 708.5 mm, range = 600.0–812.0 mm), stylet (27.6, 26.0–29.0), body width (28.3, 25.0–33.0), lip region end to posterior end of pharyngeal glands (142.5, 130.0–152.0), anal body width (15.8, 14.0–17.5), tail length (20.3, 15.0–25.0), tail annules (11.6, 10.0–14.0), a (25.0, 21.4–27.1), b (5.0, 4.4–5.7), c (35.4, 30.2–
41.7), c9 (1.3, 1.0–1.6), and V (61.8%, 60.0–63.7). The spiral nematode was identified as Helicotylenchus microlobus according to morphological and morphometric characteristics (Subbotin et al., 2015). DNA was extracted from single nematodes (n = 8) using the Proteinase K method (Kumari and Subbotin, 2012). The internal transcribed spacer (ITS) region of rDNA was amplified with the primers rDNA2/rDNA1.58S (Cherry et al., 1997). The PCR products were then purified and sequenced. The consensus ITS rDNA sequence (accession no. KY271078, 822 bp) that was deposited into the GenBank shared 99% identity with two isolates of H.microlobus from California (KM506860.1 and KM506859.1) and one isolate of H. microlobus from Spain (KM506862.1) (Subbotin et al., 2015). It had only 91% sequence identity with seven isolates of H. pseudorobustus (KM506875.1, KM506880.1, KM506876.1,KM506874.1, KM506872.1, KM506879.1, and KM506878.1) from California, Switzerland, and New Zealand, a spiral nematode species very closely related to H. microlobus in morphology. The molecular tests confirmed the identity of this spiral nematode as H.microlobus. The H. microlobus nematode was reported as one of the most commonly observed spiral nematodes in soil samples in the state of Minnesota, and all 13 soybean cultivars tested except Hawkeye were rated as hosts (Taylor, 1960). To our knowledge, this is the first report of H. microlobus in North Dakota.

Content not available PDF Share

FIGURES & TABLES

REFERENCES

  1. Cherry, T., Szalanski, T. C., Todd, T. C., and Powers, T. O. 1997. The internal transcribed spacer region of Belonolaimus (Nemata: Belonolaimidae). Journal of Nematology 29:23–29.
    [CROSSREF]
  2. Jenkins, W. R. 1964. A rapid centrifugal-flotation technique for separating nematodes from soil. Plant Disease Reporter 48:692.
    [CROSSREF]
  3. Kumari, S., and Subbotin, S. A. 2012. Molecular characterization and diagnostics of stubby root and virus vector nematodes of the family Trichodoridae (Nematoda: Triplochoda) using ribosomal RNA genes. Plant Pathology 61:1021–1031.
    [CROSSREF]
  4. Subbotin, S. A., Vovlas, N., Yeates, G. W., Hallmann, J., Kiewnick, S., Chizhov, V. N., Manzanilla-Lopez, R. H., Inserra, R. N., and Castillo, P.2015. Morphological and molecular characterization of Helicotylenchus pseudorobustus (Steiner, 1914) Golden, 1956 and related species (Tylenchida:Hoplolaimidae) with a phylogeny of the genus. Nematology 17:27–52.
    [CROSSREF]
  5. Taylor, D. P. 1960. Host range study of the spiral nematode Helicotylenchus microlobus. Plant Disease Reporter 44:747–750.
    [CROSSREF]

EXTRA FILES

COMMENTS