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Raleigh, NC, United States

Bursaphelenchus xylophilus, the pine-wood nematode (PWN), is the causal agent of pine wilt disease, one of the most damaging emerging pest problems to forests around the world. It is native to North America where it causes relatively minor damage to native conifers but is labeled an EPPO-A-2 pest and a quarantine nematode for many countries outside of the United States because of its potential for destruction to their native conifers. Exports of wood logs and commodities involving softwood packaging materials now require a lab test for the presence/absence of this regulated nematode species. We characterized the DNA sequences on the ribosomal DNA small subunit, large subunit D2/D3, internal transcribed spacer (ITS) and mitochondrial DNA cytochrome oxidase subunit one on the aphelenchid species and described the development of a real-time-PCR method for rapid and accurate identification of PWN targeting the ITS-1. A total of 97 nematode populations were used to evaluate the specificity and sensitivity of this assay, including 45 populations of B. xylophilus and 36 populations of 21 other species of Bursaphelenchus which belong to the abietinus, cocophilus, eggersi, fungivorus, hofmanni, kevini, leoni, sexdentati, and xylophilus groups and one unassigned group from a total of 13 groups in the genus Bursaphelenchus; 15 populations of Aphelenchoides besseyi, A. fragariae, Aphelenchoides species and Aphelenchus avenae; and one population of mixed nematode species from a soil sample. This assay proved to be specific to B. xylophilus only and was sensitive to a single nematode specimen regardless of the life stages present. This approach provides rapid species identification necessary to comply with the zero-tolerance export regulations.


Pedram M.,Tarbiat Modares University | Pourjam E.,Tarbiat Modares University | Robbins R.T.,University of Arkansas | Ye W.,Nematode Assay Section | Pena-Santiago R.,University of Jaen
Nematology | Year: 2011

Rhyssocolpus vinciguerrae sp. n., from natural habitats in Iran, is described, illustrated and sequenced. It is characterised by the body length of 1.04-1.37 mm, lip region offset by depression and 11-13 μm broad, odontostyle 8-10 μm or 0.7-0.8 times the lip region diam. long, neck 227-265 μm long, pharyngeal expansion 80-95 μm long or 31-35% of total neck length, a dorsal cell mass present between cardia and the end of the anterior ovary/testis, uterus bipartite, 90-170 μm long, vulva longitudinal (V = 48-55), abundant irregularities in body cuticle around vulva, female tail conical with rounded terminus (35-55 μm, c = 24-34, c′ = 1.4-1.9), spicules 43-51 μm long and 6-8 spaced ventromedian supplements located outside the range of the spicules. It is very similar to R. aquilonius, R. arcticus and R. iuventutis. A molecular characterisation of the new species was done on ribosomal DNA nearfull-length small subunit 18S gene, internal transcribed spacer and partial 5.8S gene. The results obtained support a close relationship between Rhyssocolpus and Heterodorus, and a more distant relationship with Enchodelus. © 2011 BRILL.


Aliramaji F.,Tarbiat Modares University | Pourjam E.,Tarbiat Modares University | Atighi M.R.,Tarbiat Modares University | Ye W.,Nematode Assay Section | And 2 more authors.
Russian Journal of Nematology | Year: 2014

Ektaphelenchoides poinari sp. n. is described and illustrated based on morphological, morphometric and molecular data. The new species is characterised by females with 477-565 μn long body, offset lip region 7.5-9.5 μrn wide, separated from the rest of the body by a shallow constriction, 18-23 μm long stylet lacking knobs at base, position of excretory pore at the level to slightly posterior of the metacorpus base, three incisures in lateral field, short post-uterine sac (PUS) (0.3-0.4 corresponding body width), posterior end of the body conical, males rare, spicules having rounded condylus, pointed rostrum and blunt end. The new species is close to E. attenuata, E. kelardashtensis, E. musae, E. pini, E. sylvestris and E. winteri, but differs from them by its shorter PUS, shape of posterior body end in females and males, position of vulva and excretory pore and molecular characters. Ektaphelenchoides poinari sp. n. was easily differentiated from other sequenced species by the partial small subunit rRNA gene (SSU), D2D3 expansion segment of the large subunit rRNA gene (LSU) and internal transcribed spacer 1 (ITS1). Phylogenetic analysis with these sequences suggests that E. poinari sp. n. is close to other Ektaphelenchoides species and Devibursaphelenchus. A compendium for valid species based on morphological and morphometric characters is also given.


Esmaeili M.,University of Tehran | Heydari R.,University of Tehran | Ye W.,Nematode Assay Section
Journal of Nematology | Year: 2016

Paurodontella parapitica n. sp., collected from the rhizosphere of an apple tree in Kermanshah province, western Iran, is described. The new species is characterized by a body length of 505 to 723 mm (females) and 480 to 600 mm (males), lip region continuous by depression; 7 to 8 mm broad, 3 to 4 mm high, stylet length 7 to 9 mm or 1 to 1.3 times the lip region diameter, short postuterine sac of 4 to 6 mm long, lateral fields with five to six incisures; outer incisures crenated and inner incisures weakly crenated, excretory pore situated 90 to 100 mmfrom anterior end; functional males common in the population, with spicules 24 to 26 mmlong. Tail of both sexes similar, almost straight and elongate-conoid. The new species resembles in morphology and morphometrics to four known species of the genus, namely P. apitica, P. minuta, P. myceliophaga, and P. sohailai. The results of phylogenetic analyses based on sequences of D2/D3 expansion region of 28S rRNA gene revealed this genus is polyphyletic in four different clades in Tylenchid. © The Society of Nematologists 2016.


Zeng Y.,North Carolina State University | Zeng Y.,Zhongkai University of Agriculture and Engineering | Ye W.,Nematode Assay Section | Tredway L.,North Carolina State University | And 2 more authors.
Zootaxa | Year: 2012

Twenty-nine species of plant-parasitic nematodes were recovered from 282 soil samples collected from turfgrasses in 19 counties in North Carolina (NC) and 20 counties in South Carolina (SC) during 2011 and from previous collections. These nematodes belong to 22 genera in 15 families, including Belonolaimus longicaudatus, Dolichodorus heterocephalus, Filenchus cylindricus, Helicotylenchus dihystera, Scutellonema brachyurum, Hoplolaimus galeatus, Mesocriconema xenoplax, M. curvatum, M. sphaerocephala, Ogma floridense, Paratrichodorus minor, P. allius, Tylenchorhynchus claytoni, Pratylenchus penetrans, Meloidogyne graminis, M. naasi, Heterodera sp., Cactodera sp., Hemicycliophora conida, Loofia thienemanni, Hemicaloosia graminis, Hemicriconemoides wessoni, H. chitwoodi, Paratylenchus goldeni, Xiphinema americanum sensu lato, X. bakeri, X. chambersi, Longidorus paralongicaudatus, and Aphelenchoides myceliophagus. Eleven species (Meloidogyne graminis, M. naasi, Cactodera sp., Pratylenchus penetrans, Hemicycliophora conida, Hemicaloosia graminis, Mesocriconema xenoplax, M. sphaerocephala, Ogma floridense, Paratrichodorus allius, Dolichodorus heterocephalus) were new records from turfgrass in both states; five (Heterodera sp., Loofia thienemanni, M. curvatum, Longidorus paralongicaudatus, Filenchus cylindricus) were new in SC; and three (Hemicriconemoides wessoni, Xiphinema bakeri, Aphelenchoides myceliophagus) were new in NC. The morphological and morphometric characteristics of these species are presented. Copyright © 2012 · Magnolia Press.

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