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Summary: A population of Xiphinema artemisiae was recovered from Iran, representing the first report after its original description from a meadow pasture in northern Caucasus, Russia. The Iranian population was recovered from the rhizosphere of grasses in the Damavand region, Tehran province. The females of the recovered populations are characterised by a lip region separated from the rest of body by a depression, a 5.1-5.6 mm long body, a 129-138 μ m long odontostyle, 76-85 μ m long odontophore, a uterus having a pseudo-Z-organ and crystalloid bodies observed in some specimens, and a short, rounded, dorsally more convex tail with a subcentral mucron, four juvenile developmental stages (the first stage was not recovered) and functional males. The Iranian population is morphologically and morphometrically similar to the type population and minor morphological differences can be attributed to geographical interpopulation differences. Molecular phylogenetic relationships of the Iranian population of X. artemisiae with other species were reconstructed using sequences of three genomic ribosomal markers, viz. small, large subunit D2-D3 and internal transcribed spacer (SSU, LSU D2-D3 and ITS) rDNA. [ABSTRACT FROM AUTHOR]

Summary: Criconemoides neoinformis n. sp., a cryptic species of C. informis group, and C. persicus n. sp. were recovered from the rhizosphere of pear and grass, in Zanjan and West Azerbaijan provinces, northwestern Iran, respectively. Criconemoides neoinformis n. sp. is characterised by 522-585 μ m long females, having four separated pseudolips, anteriorly flattened lip region comprised of two annuli, 57-63 retrorse body annuli with smooth to slightly crenate margins, without anastomoses, 86.9-90.4 μ m long stylet, having 6-10 annuli from vulva to posterior end and tail conical rounded with two, three or multilobed terminus and presence of males. Criconemoides persicus n. sp. could be characterised by flatly rounded lip region, having fused rectangular pseudolips, 515-615 μ m body length, stylet 60-65 μ m, body annuli 120-132 with smooth to slightly crenate margins, without anastomoses, 9-12 annuli from vulva to posterior end and tail conical rounded with two trilobed terminus. In inferred phylogenies, these two new species clustered with known Criconemoides species in 18S, 28S, ITS and COI trees. These species are clearly separated molecularly by all the studied markers. The use of molecular markers, mainly D2-D3 expansion segments of 28S rRNA, ITS region and COI , are very promising in the case of cryptic species found in this group of nematodes. We provided molecular markers (two sequences per marker) for these new species with morphological/morphometrical data using an integrative taxonomy approach for the unequivocal identification of these species. [ABSTRACT FROM AUTHOR]

Summary: Two new and one known species of Atetylenchus recovered from Dezful, Khuzestan Province, south-western Iran, are illustrated and described using morphological, morphometric and molecular data. Atetylenchus dezfuliensis n. sp. is characterised by medium-sized body 700-998 μ m long, stylet 10.0-11.5 μ m long, characteristic tail shape, first tapering regularly but then cylindrical to slightly clavate and 90-136 μ m long, phasmids located at one-third anterior part of tail and short spicules 18.7 μ m long. Atetylenchus longilabiatus n. sp. is characterised by small-sized body 593-720 μ m long, prominent lip region, stylet 9.5-12.5 μ m long, conical tail with hook-shaped terminus and 42-63 μ m long, phasmids located near mid-tail and short spicules 17.5 μ m long. Atetylenchus cf. graminus is characterised by small-sized body 643-787 μ m long, stylet 10.7-11.7 μ m long, vulva located at 51.7-55.1% of the body length, and conical tail with finely rounded end and 63-69 μ m long. Molecular data are provided for the characterisation of this genus from these two new and one known species using ribosomal genes (18S and 28S rRNA). This genus is molecularly separated from Psilenchus , but closely related in both genes. These molecular markers showed different phylogenies for both genera; partial 18S showed their relationship with Tylenchidae, while 28S rRNA showed their relationship with Merliniidae. A key to the genus is provided for species identification. [ABSTRACT FROM AUTHOR]

Summary: Sigmolenchus n. gen., is proposed as a new member of the Tylenchidae. The new genus is proposed based upon light and scanning electron microscopic (LM and SEM) observations and phylogenetic analyses based upon small, large and internal transcribed spacer sequences of ribosomal DNA (SSU, LSU D2-D3, ITS rDNA) and mitochondrial cytochrome c oxidase I gene (COI mtDNA) sequences. It is characterised partly by its slender body, but mainly by having a dorso-ventrally flattened, smooth and elevated cephalic region, unique elongate sinuous amphidial openings, each appearing as a wavy slit with three peaks, originating from the vicinity of the labial plate, extending posteriorly and reaching and passing the first body annulus, and a spacious amphidial fovea. It has an anteriorly rounded outline under LM, knobbed stylet, its conus comprising about one-third of the total length, lateral field with a single band, metacorpus with a distinct valve, vulva with small lateral flaps, and males common with tylenchoidiform spicules. The new genus is morphologically compared with seven tylenchid genera, viz., Chilenchus , Ecphyadophoroides , Filenchus , Labrys , Lelenchus , Sakia , and Tenunemellus , mainly by having small slender body and dorso-ventrally flat cephalic region, and is placed under the subfamily Ecphyadophorinae because of its slender body, elevated smooth cephalic region, long amphidial openings and spacious amphidial fovea. It was recovered from marine muddy sediments taken 2 m deep in mangrove forests off southern Iran. Currently S. sinuosus n. gen., n. sp. is monotypic. In SSU phylogeny, the new genus formed an unsupported sister relationship with Filenchus discrepans , and in LSU phylogeny it occupied a placement inside a major clade including several Tylenchinae genera. [ABSTRACT FROM AUTHOR]

The most prevalent dagger nematode recovered from rhizospheric soil samples of forest trees in the Afrātakhteh region of Golestan province (Iran) was Xiphinema afratakhtehnsis sp. nov. and it is described and illustrated with integrative approaches using both morphological and molecular criteria. It belongs to the morphospecies group 6 of the intragenic historical grouping of Xiphinema non-americanum species. The new species is characterized by females with 3.3–4.9 mm sized body, lip region separated from the rest of body by a depression, anteriorly expanded, 16–18 μm wide, vulva located at 47.2–58.5%, odontostyle 155–173 μm and odontophore 89–107 μm long, female genital system composed of two equally developed branches, the tubular part of each having spines, short symmetrically rounded female tail to symmetrically rounded with a small mucro-like projection at the end in a few females, rare males (n = 1 out of 74 females) with 83 μm long dorylaimoid spicules and four juvenile developmental stages. The third-stage juveniles (J3) have a characteristic tail shape (short, symmetrically conical with a club-shaped long mucro) demarcating the species, and being typologically useful for its separation from closely similar species (except X. cohni, with currently no data on its juvenile stages) viz. X. adenohystherum, X. iranicum, X. mazandaranense, X. nuragicum, X. pyrenaicum, X. robbinsi, X. sphaerocephalum and X. zagrosense. Molecular phylogenetic studies using genomic (partial large subunit and internal transcribed spacer 1 ribosomal RNA genes: D2-D3 and ITS1 rDNA) and mitochondrial cytochrome c oxidase subunit I gene (COI mtDNA) revealed the new species forming a unique lineage in all reconstructed trees using Bayesian inference (BI) and maximum likelihood (ML) methods. The sequenced isolates of the new species formed a monophyletic group in the D2-D3 tree. The sequenced isolates of the new species for their COI mtDNA formed four subclades in COI mtDNA phylogeny, and four haplotypes in corresponding analysis. [ABSTRACT FROM AUTHOR]

Xiphinema granatum n. sp. from pomegranate in Saveh, Markazi province, central Iran, is described and illustrated. The new species belongs to species group 8 of the genus Xiphinema sensu Loof & Luc, 1990. The new species is characterised by a body 3.5-4.1 mm long, 37-49 µm diam., odontostyle and odontophore 118-132 and 65-74 µm long, respectively, presence of sperm in the female genital tracts, uterus devoid of any Z-differentiation or spines, and abundant males with spicules 45-58 µm long. The polytomous identification codes of the new species are: A4, B4, C5a, D5, E56, F4, G23, H2, I3, J4, K2, L2. Beside morphological and morphometric data, molecular analyses of D2-D3 fragments of 28S rRNA gene placed the new species in close relationship with X. vuittenezi and X. italiae and some species belonging to Xiphinema morphospecies group 6, but clearly separated from X. index. In addition, an Iranian population of Longidorus pisi from the same locality is morphologically and molecularly characterised. [ABSTRACT FROM AUTHOR]

Two new amphimictic species, Rotylenchus iranicus n. sp. and R. conicaudatus n. sp., are described. Rotylenchus iranicus n. sp. is characterised mainly by an offset hemispherical lip region with 5-6, rarely 7, annuli, stylet 39-44 μm long, vulva located at 53-65% and rounded tail with 4-9 annuli and typical smooth tip. Morphologically this species is related to R. montanus, R. provincialis and R. aqualamus. Rotylenchus conicaudatus n. sp. is characterised mainly by a slightly offset conoid-rounded lip region with four or five, rarely six annuli, stylet 27-32 μm long, vulva located at 52-63% and conoid-rounded tail with 10-16 annuli and a typical annulated tip. Morphologically this species is related to R. pumilus, R. abnormecaudatus, R. acuspicaudatus and R. provincialis. The results of the phylogenetic analysis based on sequences of the D2-D3 expansion regions of 28S and ITS1-rRNA genes confirmed the species differentiation. Phylogenetic relationships with other species were difficult to assign using D2-D3 expansion regions of 28S. However, using ITS1-rRNA, R. conicaudatus n. sp. presented a close relationship with R. unisexus, whilst R. iranicus n. sp. was closely related to R. conicaudatus n. sp., R. unisexus, R. incultus and R. laurentinus. [ABSTRACT FROM AUTHOR]

During recent nematode surveys in a muddy soil around undetermined graminaceous plants in El Rocío, Huelva Province, in southern Spain, and from the rhizosphere of date palm associated with graminaceous vegetation from Abadan, in Khuzestan Province, south-west Iran, populations of Longidorus orientalis were identified. Morphological and morphometrical studies on these populations fit the original description and represent the first report from Spain and Europe. Molecular characterisation of L. orientalis from Spain and Iran, using D2-D3 expansion regions of 28S rRNA, 18S rRNA and ITS-rRNA, is provided. Sequences of the D2-D3 expansion regions and partial 18S genes were analysed using maximum likelihood and Bayesian inference to reconstruct phylogenetic relationships within L. orientalis and other Longidorus species. The results revealed a closer phylogenetic relationship with L. goodeyi for the D2-D3 expansion region and with L. vineacola for the partial 18S region. [ABSTRACT FROM AUTHOR]

The bud and leaf nematode, Aphelenchoides subtenuis, infecting corms and pseudostems of gladiolus in Iran, is characterised morphologically and morphometrically using a light microscope and SEM. Its relationship with similar species is discussed. The species is characterised by a sub-cylindrical female tail with hemispherical terminus bearing a single, ventrally located, mucron, well-developed postuterine sac (115 μm long) extending for ca 65% of the vulva/anus distance, presence of three lines in the lateral field, and the conoid male tail with an inconspicuous mucron. This study extends the intraspecific variability of A. subtenuis. [ABSTRACT FROM AUTHOR]

Pratylenchus loosi is an important root-lesion nematode that causes damage to tea plantations in Iran and all over the world. The present study reports on the characterization and evolution of three ß-1,4-endoglucanase genes: Pl-eng-2, Pl-eng-3 and Pl-eng-4. The gene structure of Pl-eng-2 was fully determined with the predicted signal peptide and devoid of the linker domain and carbohydrate-binding domain, while Pl-eng-3 and Pl-eng-4 were only partially sequenced. The transcription of Pl-eng-2 was localized in the secretory esophageal glands of all life stages, but it was upregulated in male and female stages. The exon/intron structures of Pl-eng-2, Pl-eng-3 and Pl-eng-4 confirmed that they resulted from gene duplication followed by sequence and gene structure diversification with loss of the linker domain and carbohydrate-binding domain during evolution. A phylogenetic analysis further confirmed that nematode endoglucanases resulted from the horizontal gene transfer of a bacterial gene, as Pl-eng-3 showed sister relationships with the CelB cellulase of Bacillus subtilis. Silencing Pl-eng-2 by in vitro RNA interference produced a 60% decrease of the transcript level. The reproductive ability of silenced P. loosi showed a 35% reduction of eggs and larval stages compared to untreated nematodes, suggesting that this gene is involved in the early steps of invasion. [ABSTRACT FROM AUTHOR]