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Kermān, Iran

Pedram M.,Tarbiat Modares University | Pourjam E.,Tarbiat Modares University | Namjou S.,Nematology Laboratory | Cantalapiedra-Navarrete C.,CSIC - Institute for Sustainable Agriculture | And 3 more authors.
Nematology | Year: 2012

Paralongidorus iranicus n. sp., a new bisexual species of the genus, is described and illustrated by light microscopy, scanning electron microscopy and molecular studies from specimens collected in the rhizosphere of Scots pine (Pinus sylvestris) from the Caspian (Khazar) seashore, Nour, northern Iran. Paralongidorus iranicus n. sp. is characterised by the large body size (7.8-11.4 mm), a rounded lip region, clearly set off by a collar-like constriction at level of, or slightly posterior to, the amphidial aperture, and bearing a very large, stirrup-shaped, amphidial fovea, with conspicuous slit-like aperture, a very long and flexible odontostyle ca 170 μm long, guiding ring located at 34 μm from anterior end and males with spicules ca 80 μm long. In addition, data from an Iranian population of P. bikanerensis recovered from the rhizosphere of palm (Phoenix dactylifera L.) in Bam, Kerman province, south-eastern Iran, agree very well and are very close to the original description of the species from India. The D2 and D3 expansion regions of 28S rRNA gene, ITS1, and 18S rRNA sequences were obtained for P. iranicus n. sp. and P. bikanerensis. Phylogenetic analyses of P. iranicus n. sp. and P. bikanerensis rRNA gene sequences and of Longidorus spp. sequences published in GenBank were done using Maximum Likelihood and Bayesian inference. Paralongidorus species (including P. iranicus n. sp.) clustered together; however, P. bikanerensis clustered within Longidorus spp. and was clearly separated from all other Paralongidorus spp. in trees generated from the D2-D3 expansion segments of 28S and partial 18S data set, respectively. © 2012 Koninklijke Brill NV, Leiden.

Atighi M.R.,Tarbiat Modares University | Pourjam E.,Tarbiat Modares University | Pedram M.,Tarbiat Modares University | Ye W.,Nematode Assay Section | And 2 more authors.
Russian Journal of Nematology | Year: 2013

Ektaphelenchoides kelardashtensis sp. n. recovered from bark samples of an unidentified tree in Mazandaran province is described and illustrated based on morphological and molecular characters. The new species is characterised by its body length of 433-577 urn in the females, a slightly off-set head, no apparent lateral field, total stylet length of 13-16 urn, excretory pore at 55-66 urn and hemizonid at 67-78 urn from anterior end, and rare males. The new species comes close in morphology and morphometries to three known species of the genus, namely E. attenuata, E. musae and E. sylvestris mostly by having a long and filiform tail (posterior body). Based on molecular data (the results of the phylogenetic comparisons), it shows more similarity to E. hunti. Compared with E. attenuata, the new species has shorter body, stylet and post-uterine sac and differences in the shape of the male tail and spicules. Compared with E. musae, the new species can be separated by its shorter body, stylet and post-uterine sac, greater index a, more anteriorly located excretory pore and hemizonid and the presence of males. Compared with E. sylvestris, the new species has a shorter stylet, greater index a, more anteriorly located vulva, hemizonid and excretory pore, difference in shape of posterior body and the presence of males. Compared with E. hunti, it has a shorter body, stylet and post-uterine sac, more anteriorly located excretory pore and hemizonid and a different shape of the posterior end. Molecular analyses were performed based on 743 bp partial ribosomal DNA large subunit D2-D3 and showed E. kelardashtensis sp. n. to be unique, but closest to E. hunti.

Sapir A.,Howard Hughes Medical Institute | Dillman A.R.,Howard Hughes Medical Institute | Dillman A.R.,Stanford University | Connon S.A.,California Institute of Technology | And 7 more authors.
Frontiers in Microbiology | Year: 2014

The deep sea is Earth's largest habitat but little is known about the nature of deep-sea parasitism. In contrast to a few characterized cases of bacterial and protistan parasites, the existence and biological significance of deep-sea parasitic fungi is yet to be understood. Here we report the discovery of a fungus-related parasitic microsporidium, Nematocenator marisprofundi n. gen. n. sp. that infects benthic nematodes at methane seeps on the Pacific Ocean floor. This infection is species-specific and has been temporally and spatially stable over 2 years of sampling, indicating an ecologically consistent host-parasite interaction. A high distribution of spores in the reproductive tracts of infected males and females and their absence from host nematodes' intestines suggests a sexual transmission strategy in contrast to the fecal-oral transmission of most microsporidia. N. marisprofundi targets the host's body wall muscles causing cell lysis, and in severe infection even muscle filament degradation. Phylogenetic analyses placed N. marisprofundi in a novel and basal clade not closely related to any described microsporidia clade, suggesting either that microsporidia-nematode parasitism occurred early in microsporidia evolution or that host specialization occurred late in an ancient deep-sea microsporidian lineage. Our findings reveal that methane seeps support complex ecosystems involving interkingdom interactions between bacteria, nematodes, and parasitic fungi and that microsporidia parasitism exists also in the deep-sea biosphere. © 2014 Sapir, Dillman, Connon, Grupe, Ingels, Mundo-Ocampo, Levin, Baldwin, Orphan and Sternberg.

Carta L.K.,Nematology Laboratory | Skantar A.M.,Nematology Laboratory | Handoo Z.A.,Nematology Laboratory | Baynes M.A.,University of Idaho
Nematology | Year: 2011

Nematodes were isolated from surface-sterilised stems of cheatgrass, Bromus tectorum (Poaceae), in Colorado, grown on Fusarium (Hypocreaceae) fungus culture, and identified as Paraphelenchus acontioides. Morphometrics and micrographic morphology of this species are given to supplement the original description and expand the comparative species diagnosis. A tabular morphometric compendium of the females of the 23 species of Paraphelenchus is provided as the last diagnostic compilation was in 1984. Variations in the oviduct within the genus are reviewed to evaluate the taxonomic assignment of P. deckeri, a morphologically transitional species between Aphelenchus and Paraphelenchus. Sequences were generated for both 18S and 28S ribosomal DNA, representing the first identified species within Paraphelenchus so characterised. These sequences were incorporated into phylogenetic trees with related species of Aphelenchidae and Tylenchidae. Aphelenchus avenae isolates formed a well supported monophyletic sister group to Paraphelenchus. The ecology of Paraphelenchus, cheat grass and Fusarium is also discussed. © 2011 BRILL.

Nischwitz C.,Utah State University | Skantar A.,Nematology Laboratory | Handoo Z.A.,Nematology Laboratory | Hult M.N.,Nematology Laboratory | And 2 more authors.
Plant Disease | Year: 2013

Several species of root-knot nematodes (Meloidogyne spp.) are known to have significant presence on turfgrass in golf course greens, particularly in the western United States. Nematodes isolated from a golf course in King County, WA were identified as Meloidogyne minor based on analysis of the large ribosomal subunit (LSU 28S D2-D3 expansion segment), the internal transcribed spacers 1 and 2 (ITS rDNA), the intergenic spacer region 2 (IGS2), and the nuclear protein coding gene Hsp90. Sequence-characterized amplified region (SCAR) primers that were originally designed to be specific for M. fallax were found to cross-react with M. minor. A population from California was determined to be M. fallax based on juvenile tail morphology and analysis of the ribosomal markers and Hsp90, comprising the first report of this species in North America. Using trees based on Hsp90 genomic alignments, the phylogenetic relationships of these populations and known root-knot nematode species were congruent with previous trees based on ribosomal genes. Resolution of M. fallax and M. chitwoodi using Hsp90 was equivalent to species separation obtained with 28S or 18S rDNA alignments. The strengths and weaknesses of ribosomal and Hsp90 markers, and the use of SCAR polymerase chain reaction as diagnostic tools are discussed.

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