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Summary: A new species of the genus Talanema , T. maculatum sp. n., collected in a natural enclave of Iran, is characterised on the basis of morphological and molecular data. It is distinguishable by its 1.82-2.20 mm long body, lip region offset by constriction and 20-23 μ m wide with perioral liplets, odontostyle 21.5-28 μ m long, guiding ring double, neck 394-525 μ m long, pharyngeal expansion occupying 44-49% of the total neck length, uterus tripartite and 308-441 μ m long or 5.1-6.8 body diam., vulva transverse (V = 54-58), presence of abundant cuticle irregularities at the perivulval area, tail similar in both sexes, conical with a dorsal concavity (31-45 μ m, c = 46-71, c′ = 0.9-1.1), spicules 70-75 μ m long, and 14-18 shortly spaced ventromedian supplements ending at level of the anterior end of spicules, with hiatus. Molecular analysis of 28S-rDNA gene confirms the monophyly of Talanema and the difficulties in elucidating its external evolutionary relationships. [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: A new species of Tylenchidae from the rhizosphere of mangrove trees in Hormozgan and Khuzestan provinces, Iran, is described based on morphological and molecular data. Ottolenchus sinipersici n. sp., is characterised by a slightly fusiform body 560-665 μ m long, lateral field in the form of a narrow band with two faint incisures that are not visible in fatter females, indistinct transverse annuli under the light microscope, cephalic region continuous with the body contour, smooth and flattened dorsoventrally, longitudinal and narrow sigmoid amphidial slits, stylet delicate, 10.1-11.2 μ m long, with small rounded to slightly posteriorly sloping knobs, well-developed median bulb, offset and pyriform pharyngeal basal bulb, vulva located at 66.9-69.6% of body length, offset spermatheca, short post-vulval uterine sac, spicules 18.5-20.5 μ m long with highly curved blades, and a 113-135 μ m long filiform tail with a hook-like or coiled terminus. In Bayesian inference phylogenetic trees based on the partial small subunit ribosomal DNA (SSU rDNA) and D2-D3 expansion segment of large subunit ribosomal DNA (D2-D3 LSU rDNA) genes, the new species clustered together with O. facultativus (KJ869310) in SSU, and forms a clade with three isolates of O. discrepans in LSU phylogeny. Ottolenchus fungivorus n. comb. (= Filenchus fungivorus) is proposed. [ABSTRACT FROM AUTHOR]

Summary: A new species of Coslenchus from north-western Iran is illustrated and described using morphological, morphometric and molecular data. Coslenchus persicus n. sp. is characterised by a medium-sized body of 694-810 μ m, often 18 (seldom 20-22) longitudinal ridges excluding lateral field, head with four distinct annuli, stylet 9.6-10.8 μ m long, pharyngeal basal bulb large and cylindrical, spermatheca offset and ovate, without sperm, vulval flaps extending for two annuli, 5-7 μ m in length, tail striated with finely to bluntly rounded tip, 110-153 μ m long and without males. The new species comes close to C. assamensis , C. diversus , C. japonicus , C. leiocephalus , C. maritus , C. multigyrus , C. paramaritus , C. pastor , and C. polonicus , but can be distinguished from all by differences in body length, stylet length and shape of basal bulb, post-vulval uterine sac, tail and certain morphometric data. Molecular data are provided for the characterisation of the new species using ribosomal genes (18S and 28S rRNA). In the 18S rRNA tree, the new species was placed in a clade including one isolate of Coslenchus sp. from Iran. In the reconstructed 28S rRNA phylogenetic tree, C. persicus n. sp. clustered with other known Coslenchus species. [ABSTRACT FROM AUTHOR]

A survey was conducted during 2018 and 2019 in order to identify plant-parasitic nematodes of the genus Basiria in Dezful region of Khuzestan province, southwestern Iran. Nematodes were extracted from the soil and root samples by using tray method, transferred to glycerin and mounted on permanent slides. Nematodes were identified based on morphological and morphometric characters. As a result, eight species including B. aberrans, B. duplexa, B. gracilis, B. jirians, B. tumida, B. graminophila, B. ritteri, and B. similis were identified; three species namely B. jirians, B. ritteri, and B. similis are here described and illustrated for the first time from Iran. B. jirians is characterized by body length 445-535 μm, stylet 9.0-9.2 μm, cephalic region without annuli, DGO 2.0-2.5 μm, median bulb at anterior end of pharynx, basal bulb pyriform, spermatheca non offset and tail elongate conoid with pointed to filiform terminus. B. ritteri can be characterized by body length 685-747 μm, stylet 10.5-11.5 μm, median bulb located at anterior half of pharynx, basal bulb cylindroid, spermatheca non offset and tail annulated and notched at tip. B. similis is characterized by body length 644-736 μm, stylet 10.3-11 μm, DGO 8.9-10.5 μm, basal bulb cylindroid and tail clavate. [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: An undescribed species from the rhizosphere of tamarisk, Tamarix passerinoides , Telotylenchus tamariscus n. sp., is illustrated and described based on morphological, morphometric and molecular approaches. The new species is characterised by female characters including body size of ca 1 mm, areolated lateral fields, cephalic region rounded, distinctly set off from the body contour, stylet 19.5 (18.5-20.5) μ m long with posteriorly directed basal knobs, pharyngeal glands overlapping intestine dorso-laterally, subcylindrical tail bearing 32 (25-37) cuticular annuli and ending in an annulated terminus, and male spicules and gubernaculum 27 (25-29) and 13 (12.5-14.5) μ m long, respectively. Morphologically, our population comes close to several known species of the genus, including T. avaricus , T. aerolatus , T. indicus , T. ventralis , T. paaloofi and T. namibiensis. In the 18S rRNA phylogenetic tree, it occupied a phylogenetic position in close affinity with two sequences of T. ventralis. In the 28S rRNA tree, the genus Telotylenchus did not form a monophyletic group, our isolate clustering with an unknown population of Histotylenchus and four isolates of Tylenchorhynchus mediterraneus in a clade well separated from another clade that included three other isolates tentatively named as Telotylenchus sp. [ABSTRACT FROM AUTHOR]

Summary: In this study, we provide morphological and molecular characterisation of three known species of the Criconematoidea, namely Criconema cylindraceum , Paratylenchus alleni and P. steineri , recovered from Iran. Descriptions, morphometric data, drawings and photomicrographs are provided, and comparisons are made with closely related species. Phylogenetic analysis using the D2-D3 expansion segments of the 28S rRNA gene revealed that C. cylindraceum formed a cluster with Ogma decalineatus , a species with a similar head structure, but with differences in cuticle ornamentation, tail shape and morphometric characters. Moreover, P. alleni grouped with species of Paratylenchus having four lateral lines and a short stylet (< 40 μ m), exceptionally including the unresolved P. straeleni , while P. steineri formed a clade with long stylet species, including P. teres and P. wuae. The taxonomic placement of C. cylindraceum in Criconema , rather than in Criconemoides , is justified, and P. teres is molecularly differentiated from P. steineri , the two species differing in having or lacking a stylet in the fourth-stage juvenile. [ABSTRACT FROM AUTHOR]

Mesocriconema abolafiai n. sp. is described by morphological, morphometric, and molecular approaches. The new species is characterized by a body slightly curved with 402 to 612 μ m length, 90 to 113 cuticular body annuli with smooth to irregular margins lacking of crenation with not more than one anastomoses, lip region not offset, small flattened submedian lobes, stylet robust (52.8-60.0 μm) with well-developed knobs, open vulva with simple anterior lip, straight vagina, filled spermatheca with globular sperms, presence of males, and conical-acute tail with last annulus bilobed or rounded. Discussions are made on the characterization of M. abolafiai n. sp. from the most closely related species, M. ozarkiense, and several other species having similar tail shape. Furthermore, results of phylogenetic analyses inferred from D2 to D3 expansion fragments of 28S rRNA, 18S rRNA, and ITS rRNA gene sequences revealed the phylogenetic position of the new species within representatives of Criconematidae and supported morphological justifications for considering this population from Iran as a new species in the genus Mesocriconema. [ABSTRACT FROM AUTHOR]

Summary: The second population of Pratylenchoides riparius , including females and males, is described and illustrated based upon morphological, morphometric and molecular data. The present population from Iran is characterised by some differences with the type population of the species from Hungary in stylet length (24-26 vs 21-22 μ m), slightly longer body (1002-1230 vs 830-960 μ m), pharynx (202-211 vs 182-190 μ m) and tail (64-85 vs 48-57 μ m), areolated outer bands of the lateral field (vs non-areolated), widening of the lateral field near tail terminus (vs lateral incisures connecting each other) and presence of males (vs absent). The taxonomic status of the species with regarding the data from the type and presently recovered population, as well as the closely similar species is discussed. The newly recovered population was studied based upon its molecular phylogenetic charactes using the D2-D3 of 28S rRNA and the partial 18S rRNA gene sequences and the results revealed that it forms a clade with P. magnicauda in 28S, but occupies a distant placement from it in 18S phylogeny. [ABSTRACT FROM AUTHOR]

Two populations of the genus Trophotylenchulus and 10 species of the genus Paratylenchus from Iran were characterized based on morphometric, morphological and molecular characters. Our observations on the two populations of Trophotylenchulus from Iran revealed that T. asoensis and T. okamotoi have been distinguished from T. arenarius, on the basis of the features which cannot be longer considered as stable diagnostic characters. One of the populations shows a mixed combination of the characters of T. arenarius and T. asoensis; it has morphometrics more similar to T. arenarius but shows affinities with T. asoensis in the tail terminus shape of females and second-stage juveniles (J2) and in having a reduced stylet in males. The other population fit well with T. okamotoi; it has females with generally bluntly rounded tails typical for T. okamotoi, but sometimes with finely rounded tail termini, like those of T. arenarius or T. asoensis. The sequences of D2-D3 expansion segments of 28 S rRNA gene for the two populations are identical with each other, but only 4 bp (0.67%) difference with T. arenarius sequence deposited in the GenBank. Considering no stable difference allow separating species, synonymy of T. asoensis and T. okamotoi with T. arenarius, which has already been proposed, is supported and confirmed here. All studied Paratylenchus species with stylets longer than 40 µm, except P. straeleni, formed a basal cluster to Cacopaurus pestis and species of Paratylenchus bearing stylets shorter than 40 µm; thus, validity of Gracilacus cannot be rejected using our data sets. However, the synonymy of Paratylenchoides was supported by the positioning of P. sheri within representatives of Paratylenchus in the inferred phylogenetic tree. [ABSTRACT FROM AUTHOR]

To investigate relationships within the subfamily Telotylenchinae, more than 500 soil samples were collected from various natural and agricultural habitats in several localities of Iran. Individuals of seven known species, including Bitylenchus dubius, B. parvus, B. serranus, Sauertylenchus maximus, Tylenchorhynchus clarus, T. microconus and Trophurus ussuriensis, were recovered and characterized based on morphological and morphometric characters. Furthermore, phylogenetic relationships within representatives of the subfamily Telotylenchinae were explored using 13 sequences from the D2-D3 expansion regions of 28S ribosomal (r) DNA and 13 sequences for the partial 18S rDNA genes obtained in the present study. Analyses based on the relatively conserved 18S rDNA gene underlined the polyphyletic status of Tylenchorhynchus sensu lato, as three clusters representing Tylenchorhynchus, Bitylenchus and Sauertylenchus were well separated, and interspersed by, e.g., representatives of the Macrotrophurinae. Analysis of the more variable D2-D3 28S rDNA sequences suggested at least four clades within the subfamily Telotylenchinae: two clades dominated by Tylenchorhynchus species; a third clade harbouring representatives of Sauertylenchus, Bitylenchus, and Paratrophurus in distinct but unresolved branches;and a fourth clade dominated by Trophurus species. Although no molecular information was available from a number of genera that were originally gathered under Tylenchorhynchus sensu lato, we concluded that both Bitylenchus and Sauertylenchus should be seen as valid Telotylenchinae genera related to, but distinct from Tylenchorhynchus.

The present work is a compilation of the systematics of the genus Tylolaimophorus (Nematoda: Diphtherophoridae). These nematodes are soil inhabitants that occur mostly in the vicinity of plant roots. An historical taxonomy, amended diagnosis and several taxonomic remarks on the genus are discussed here. A list of all 13 globally known species (and their synonyms) is given and all of them are treated here. For each species, taxonomic information including morphometric data reported worldwide, amended descriptions of females and males, diagnosis of the species and its relationships with closely related species, as well as its distribution and associated plants are discussed. Moreover, based on the most important morphological and morphometric characters, an identification key and a diagnostic compendium to the species are included. Two populations of T. minor are described and illustrated for the first time from Iran. Comparing morphological and morphometric characteristics of the Iranian populations with other populations worldwide reveals that these populations share almost all diagnostic characters except spear length, which is slightly longer in the Russian populations as compared with populations from USA, Poland and Iran.

Perennial plants and their associated microorganisms grow in the areas that may be contaminated with long-lived gamma-emitting radionuclides. This will induce gamma stress response in plants and their accompanying microorganisms. The present work investigated the growth and physiological responses of Epichloe endophyte infected tall fescue to gamma radiation, as well as whether the endophyte could persist and infect the host plant once exposed to gamma radiation. Seeds of Iranian native genotype of 75B + of tall fescue were exposed to different doses, including 5.0, 10.0, 15.0, 20.0, 30.0 and 40.0 krad of gamma ray from a 60 Co source. Irradiated and unirradiated seeds were sown in pots and grown under controlled conditions in the greenhouse. The growth and physiological parameters associated with plant tolerance to oxidative stress of host plants, as well as endophytic infection frequency (% of plants infected) and intensity (mean number of endophytic hyphae per the field of view), were examined in 3 months-old seedlings. The results indicated that all gamma radiation doses (except 5.0 kr) significantly reduced the height and survival percentage of the host plant. Days to the emergence of seedling increased gradually as gamma doses rose. A dose-rate dependent induction was seen for photosynthetic pigments and proline content. Malondialdehyde (MDA) content grew with elevation of irradiation doses. Depending on the dose and time, the activities of antioxidant enzymes in the host plant responded differently to gamma radiation. Gamma radiation altered the enzyme activities with sever decline in SOD and CAT activities. However, it had barely any effect on in APX and POD activities. The results also revealed that the persistence and intensity of endophyte were affected after gamma-ray irradiation. The initial percentage of tall fescue seeds infected with the endophyte was 91% in un-irradiated seeds. Presence of the viable endophyte started to decline significantly (23%) at 5.0 kr of gamma radiation. A dramatic reduction in the presence and intensity of endophyte occurred at 10.0 to 40.0 kr intensities. Gamma radiation × trait (GT)-biplot analysis indicated positive correlations between the endophyte symbiosis and antioxidant enzyme activities. Also, negative correlations were observed between the endophyte and MDA content in the host plant. Our results suggest that radiation stress (doses over 5.0 kr) caused reduction in the growth and antioxidant enzyme activities of the host plant that accompanied by a dramatic reduction in the persistence and intensity of endophyte fungi. Our findings have provided the basic information for future studies on the effect of gamma irradiation on the interaction between endophytic fungi and its host plant., (Copyright © 2019 Elsevier Inc. All rights reserved.)