Dataset Information

Mitochondrial genome diversity in dagger and needle nematodes (Nematoda: Longidoridae).

ABSTRACT: Dagger and needle nematodes included in the family Longidoridae (viz. Longidorus, Paralongidorus, and Xiphinema) are highly polyphagous plant-parasitic nematodes in wild and cultivated plants and some of them are plant-virus vectors (nepovirus). The mitochondrial (mt) genomes of the dagger and needle nematodes, Xiphinema rivesi, Xiphinema pachtaicum, Longidorus vineacola and Paralongidorus litoralis were sequenced in this study. The four circular mt genomes have an estimated size of 12.6, 12.5, 13.5 and 12.7?kb, respectively. Up to date, the mt genome of X. pachtaicum is the smallest genome found in Nematoda. The four mt genomes contain 12 protein-coding genes (viz. cox1-3, nad1-6, nad4L, atp6 and cob) and two ribosomal RNA genes (rrnL and rrnS), but the atp8 gene was not detected. These mt genomes showed a gene arrangement very different within the Longidoridae species sequenced, with the exception of very closely related species (X. americanum and X. rivesi). The sizes of non-coding regions in the Longidoridae nematodes were very small and were present in a few places in the mt genome. Phylogenetic analysis of all coding genes showed a closer relationship between Longidorus and Paralongidorus and different phylogenetic possibilities for the three Xiphinema species.

SUBMITTER: Palomares-Rius JE

PROVIDER: S-EPMC5288807 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Mitochondrial genome diversity in dagger and needle nematodes (Nematoda: Longidoridae).

Palomares-Rius J E JE Cantalapiedra-Navarrete C C Archidona-Yuste A A Blok V C VC Castillo P P

Scientific reports 20170202

Dagger and needle nematodes included in the family Longidoridae (viz. Longidorus, Paralongidorus, and Xiphinema) are highly polyphagous plant-parasitic nematodes in wild and cultivated plants and some of them are plant-virus vectors (nepovirus). The mitochondrial (mt) genomes of the dagger and needle nematodes, Xiphinema rivesi, Xiphinema pachtaicum, Longidorus vineacola and Paralongidorus litoralis were sequenced in this study. The four circular mt genomes have an estimated size of 12.6, 12.5, ...[more]

PMID: 28150734

Similar Datasets

Project description:The genus Xiphinema includes a remarkable group of invertebrates of the phylum Nematoda comprising ectoparasitic animals of many wild and cultivated plants. Damage is caused by direct feeding on root cells and by vectoring nepoviruses that cause diseases on several crops. Precise identification of Xiphinema species is critical for launching appropriate control measures. We make available the first detailed information on the diversity and distribution of Xiphinema species infesting wild and cultivated olive in a wide-region in southern Spain that included 211 locations from which 453 sampling sites were analyzed. The present study identified thirty-two Xiphinema spp. in the rhizosphere of olive trees, ten species belonging to Xiphinema americanum-group, whereas twenty-two were attributed to Xiphinema non-americanum-group. These results increase our current knowledge on the biodiversity of Xiphinema species identified in olives and include the description of four new species (Xiphinema andalusiense sp. nov., Xiphinema celtiense sp. nov., Xiphinema iznajarense sp. nov., and Xiphinema mengibarense sp. nov.), and two new records for cultivate olives (X. cadavalense and X. conurum). We also found evidence of remarkable prevalence of Xiphinema spp. in olive trees, viz. 85.0% (385 out of 453 sampling sites), and they were widely distributed in both wild and cultivated olives, with 26 and 17 Xiphinema spp., respectively. Diversity indexes (Richness, Hill´s diversity, Hill´s reciprocal of D and Hill´s evenness) were significantly affected by olive type. We also developed a comparative morphological and morphometrical study together with molecular data from three nuclear ribosomal RNA genes (D2-D3 expansion segments of 28S, ITS1, and partial 18S). Molecular characterization and phylogenetic analyses allowed the delimitation and discrimination of four new species of the genus described herein and three known species. Phylogenetic analyses of Xiphinema spp. resulted in a general consensus of these species groups. This study is the most complete phylogenetic analysis for Xiphinema non-americanum-group species to date.

Project description:The genus Longidorus includes a remarkable group of invertebrate animals of the phylum Nematoda comprising polyphagous root-ectoparasites of numerous plants including several agricultural crops and trees. Damage is caused by direct feeding on root cells as well as by transmitting nepoviruses that cause disease on those crops. Thus, correct identification of Longidorus species is essential to establish appropriate control measures. We provide the first detailed information on the diversity and distribution of Longidorus species infesting wild and cultivated olive soils in a wide-region in southern Spain that included 159 locations from which 449 sampling sites were analyzed. The present study doubles the known biodiversity of Longidorus species identified in olives by including six new species (Longidorus indalus sp. nov., Longidorus macrodorus sp. nov., Longidorus onubensis sp. nov., Longidorus silvestris sp. nov., Longidorus vallensis sp. nov., and Longidorus wicuolea sp. nov.), two new records for wild and cultivate olives (L. alvegus and L. vineacola), and two additional new records for wild olive (L. intermedius and L. lusitanicus). We also found evidence of some geographic species associations to western (viz. L. alvegus, L. intermedius, L. lusitanicus, L. onubensis sp. nov., L. vineacola, L. vinearum, L. wicuolea sp. nov.) and eastern distributions (viz. L. indalus sp. nov.), while only L. magnus was detected in both areas. We developed a comparative study by considering morphological and morphometrical features together with molecular data from nuclear ribosomal RNA genes (D2-D3 expansion segments of 28S, ITS1, and partial 18S). Results of molecular and phylogenetic analyses confirmed the morphological hypotheses and allowed the delimitation and discrimination of six new species of the genus described herein and four known species. Phylogenetic analyses of Longidorus spp. based on three molecular markers resulted in a general consensus of these species groups, since lineages were maintained for the majority of species. This study represents the most complete phylogenetic analysis for Longidorus species to date.

Project description:Three populations of Xiphinema primum n. sp. and two populations of X. pachtaicum were recovered from natural forests and cultural regions of northern Iran. Both species belong to the X. americanum-group and were characterized by their morphological, morphometric and molecular data. The new species, which was recovered in three locations, belongs to the X. brevicolle-complex and is characterized by 2124-2981 μm long females with a widely rounded lip region separated from the rest of the body by a depression, 103-125 μm long odontostyle, two equally developed genital branches with endosymbiont bacteria inside the ovary, which are visible under light microscope (LM), vulva located at 51.8-58.0%, the tail is 26-37 μm long with a bluntly rounded end and four juvenile developmental stages. It was morphologically compared with nine similar species viz. X. brevicolle, X. diffusum, X. incognitum, X. himalayense, X. luci, X. parabrevicolle, X. paramonovi, X. parataylori and X. taylori. The second species, X. pachtaicum, was recovered in two geographically distant points close to city of Amol. Molecular phylogenetic studies of the new species were performed using partial sequences of the D2-D3 expansion segments of the large subunit ribosomal RNA gene (LSU rDNA D2-D3), the internal-transcribed spacer rDNA (ITS = ITS1+5.8S+ITS2), and the mitochondrial cytochrome c oxidase I gene (COI mtDNA) regions. The Iranian population of X. pachtaicum was also phylogenetically studied based upon its LSU rDNA D2-D3 sequences. Both species were also inspected for their putative endosymbiont bacteria. Candidatus Xiphinematobacter sp. was detected from two examined populations of the new species, whereas the second endosymbiont bacterium, detected from three examined isolates of X. pachtaicum, was related to the plant and fungal endosymbionts of the family Burkholderiaceae. The phylogenetic analyses of the two endosymbiont bacteria were performed using partial sequences of 16S rDNA. In cophylogenetic analyses, significant levels of cophylogenetic signal were observed using both LSU rDNA D2-D3 and COI mtDNA markers of the host nematodes and 16S rDNA marker of the endosymbiont bacteria.

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Dataset Information

Mitochondrial genome diversity in dagger and needle nematodes (Nematoda: Longidoridae).

Publications

Mitochondrial genome diversity in dagger and needle nematodes (Nematoda: Longidoridae).

Similar Datasets

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