scholarly journals Characterization of the mycobiome of the seagrass, Zostera marina, reveals putative associations with marine chytrids

2019 ◽  
Author(s):  
Cassandra L. Ettinger ◽  
Jonathan A. Eisen
Keyword(s):  
Zostera Marina ◽  
Marine Fungi ◽  
Its Region ◽  
Taxonomic Diversity ◽  
Its2 Region ◽  
Rrna Gene ◽  
Sequence Variant ◽  
28S Rrna ◽  
Taxonomic Assignment ◽  
28S Rrna Gene

AbstractSeagrasses are globally distributed marine flowering plants that are foundation species in coastal ecosystems. Seagrass beds play essential roles as habitats and hatcheries, in nutrient cycling and in protecting the coastline from erosion. Although many studies have focused on seagrass ecology, only a limited number have investigated their associated fungi. In terrestrial systems, fungi can have beneficial and detrimental effects on plant fitness. However, not much is known about marine fungi and even less is known about seagrass associated fungi. Here we used culture-independent sequencing of the ribosomal internal transcribed spacer (ITS) region to characterize the taxonomic diversity of fungi associated with the seagrass, Zostera marina. We sampled from two Z. marina beds in Bodega Bay over three time points to investigate fungal diversity within and between plants. Our results indicate that there are many fungal taxa for which a taxonomic assignment cannot be made living on and inside Z. marina leaves, roots and rhizomes and that these plant tissues harbor distinct fungal communities. The most prevalent ITS amplicon sequence variant (ASV) associated with Z. marina leaves was classified as fungal, but could not initially be assigned to a fungal phylum. We then used PCR with a primer targeting unique regions of the ITS2 region of this ASV and an existing primer for the fungal 28S rRNA gene to amplify part of the 28S rRNA gene region and link it to this ASV. Sequencing and phylogenetic analysis of the resulting partial 28S rRNA gene revealed that the organism that this ASV comes from is a member of Novel Clade SW-I in the order Lobulomycetales in the phylum Chytridiomycota. This clade includes known parasites of freshwater diatoms and algae and it is possible this chytrid is directly infecting Z. marina leaf tissues. This work highlights a need for further studies focusing on marine fungi and the potential importance of these understudied communities to the larger seagrass ecosystem.

scholarly journals Global diversity and biogeography of the Zostera marina mycobiome

2020 ◽  
Author(s):  
Cassandra L. Ettinger ◽  
Laura E. Vann ◽  
Jonathan A. Eisen
Keyword(s):  
Fungal Community ◽  
Community Assembly ◽  
Zostera Marina ◽  
Plant Pathogens ◽  
High Throughput Sequencing ◽  
Marine Fungi ◽  
Its Region ◽  
Global Distribution ◽  
Rrna Gene ◽  
Fungal Community Composition

AbstractSeagrasses are marine flowering plants that provide critical ecosystem services in coastal environments worldwide. Marine fungi are often overlooked in microbiome and seagrass studies, despite terrestrial fungi having critical functional roles as decomposers, pathogens or endophytes in global ecosystems. Here we characterize the distribution of fungi associated with the seagrass, Zostera marina, using leaves, roots, and rhizosphere sediment from 16 locations across its full biogeographic range. Using high throughput sequencing of the ribosomal internal transcribed spacer (ITS) region and 18S ribosomal RNA gene, we first measured fungal community composition and diversity, then we tested hypotheses of neutral community assembly theory and the degree to which deviations suggested amplicon sequence variants (ASVs) were plant-selected or dispersal-limited, and finally we identified a core mycobiome and investigated the global distribution of differentially abundant ASVs. Our results show that the fungal community is significantly different between sites and follows a weak, but significant pattern of distance decay. Generally, there was evidence for both deterministic and stochastic factors contributing to community assembly of the mycobiome. The Z. marina core leaf and root mycobiomes are dominated by unclassified Sordariomycetes spp., unclassified Chytridiomycota lineages (including Lobulomycetaceae spp.), unclassified Capnodiales spp. and Saccharomyces sp. A few ASVs (e.g. Lobulomyces sp.) appear restricted to one or a handful of locations (e.g. possibly due to local adaptation, deterministic dispersal limitation or seasonal bloom events), while others (e.g. Saccharomyces sp.) are more ubiquitous across all locations suggesting a true global distribution and possible plant-selection. Fungal guilds associated with Z. marina were only weakly identified (10.12% of ITS region and 3.4% 18S rRNA gene ASV guild assignments were considered highly probable) including wood saprotrophs, ectomycorrhizal fungi, endophytic fungi and plant pathogens. Our results are similar to those found for other seagrass species. It is clear from the many unclassified fungal ASVs and fungal functional guilds, that our knowledge of marine fungi is still rudimentary. Further studies characterizing seagrass-associated fungi are needed to understand the roles of these microorganisms generally and when associated with seagrasses.

Description of Longidorus barsii Radivojević & De Luca sp. n. (Nematoda: Longidoridae) from Serbia and observations on some taxonomic characters

Nematology ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 555-576
Author(s):  
Milan Radivojević ◽  
László Barsi ◽  
Elena Fanelli ◽  
Francesca De Luca
Keyword(s):  
Its Region ◽  
Balkan Peninsula ◽  
Body Region ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Oral Aperture ◽  
Dorsal Nucleus ◽  
28S Rrna Gene ◽  
Anterior Body

Summary Longidorus barsii sp. n., from Mt Tara in the Balkan Peninsula, is described and characterised by using a polyphasic approach. The species has numerous males. The female body is 5-7 mm long, rather stout and resembles a large Xiphinema. The lip region is wide, with rounded sides continuous with the neck, frontally flattened and depressed around the oral aperture, amphids are pouch-like and distinctly bi-lobed and the odontostyle is moderately long. The nuclei of the pharyngeal glands are in the normal position, the dorsal nucleus located somewhat posterior to anterior third of bulb. The uteri are long, the distal inner epithelium densely covered with papilla-like outgrowths. The tail is rounded, bluntly conoid and very short. Alpha-numerical identification codes: A4/5, B45, C3, D3, E2, F3, G 1(2), H1, I2, J1, K67. The morphologically most similar species are L. kheirii, L. polyae and L. profundorum. Additional observations are provided on the anterior body region and genital organs in L. barsii sp. n., L. piceicola, L. silvae, and L. uroshis. Selected features are discussed from the taxonomic and functional points of view. The D2-D3 expansion domains of the 28S rRNA gene and the ITS region of L. barsii sp. n. were amplified and sequenced. Phylogenetic analysis using the D2-D3 expansion domains of the 28S rRNA gene revealed close evolutionary relationships with L. polyae, L. athesinus and three unidentified Longidorus spp.

scholarly journals Intra-species sequence variability in 28s rRNA gene of Oesophagostomum venulosum isolated from goats of West Bengal, India

2010 ◽  
Vol 3 (7) ◽  
pp. 515-518 ◽  
Author(s):  
Subhasish Bandyopadhyay ◽  
Asit Kumar Bera ◽  
Sourav Sikdar ◽  
Sumanta De ◽  
Subhashree Ghosh ◽  
...  
Keyword(s):  
West Bengal ◽  
Rrna Gene ◽  
28S Rrna ◽  
Sequence Variability ◽  
28S Rrna Gene

scholarly journals Phylogenetic Analysis of 28S rRNA Gene of Indigenous Xiphinema pachydermum

2019 ◽  
Vol 8 (07) ◽  
pp. 1960-1968
Author(s):  
Anju Sharma ◽  
Satish K. Sharma ◽  
Kiran Rana ◽  
Anil Kumar Verma
Keyword(s):  
Phylogenetic Analysis ◽  
Rrna Gene ◽  
28S Rrna ◽  
28S Rrna Gene

Stephanoprora amurensis sp. nov., Echinochasmus milvi Yamaguti, 1939 and E. suifunensis Besprozvannykh, 1991 from the Russian southern Far East and their phylogenetic relationships within the Echinochasmidae Odhner 1910

Parasitology ◽  
2020 ◽  
Vol 147 (13) ◽  
pp. 1469-1479
Author(s):  
Y. V. Tatonova ◽  
A. V. Izrailskaia ◽  
V. V. Besprozvannykh
Keyword(s):  
Dna Markers ◽  
Phylogenetic Relationships ◽  
Developmental Stages ◽  
Far East ◽  
Genetic Data ◽  
Freshwater Snails ◽  
Its2 Region ◽  
Rrna Gene ◽  
28S Rrna ◽  
Southern Far East

AbstractMature worms of Stephanoprora amurensis sp. nov. were obtained in an experimental study of its life cycle. In the Russian southern Far East, this trematode circulates using freshwater snails Parajuga subtegulata, freshwater fish and birds as the first, second intermediate and final hosts, respectively. Stephanoprora amurensis sp. nov. differs from the well-known representatives of Stephanoprora in a number of morphometric indicators of the developmental stages. The validity of the species was also confirmed by nuclear and mitochondrial DNA markers. In addition, new genetic data were obtained for Echinochasmus suifunensis and Echinochasmus milvi. An analysis of phylogenetic relationships within Echinochasmidae based on the 28S rRNA gene and ITS2 region identified two clusters, one of which combines species of Echinochasmus with 20–22 collar spines and short-tailed cercariae, and the other which includes Stephanoprora spp. and a number of representatives of Echinochasmus with 24 collar spines and long-tailed cercariae. The results of phylogenetic analysis based on ITS2 data show interfamily level of differences between the two clusters and intergeneric differentiation between the three subclusters uniting the species of Stephanoprora and Echinochasmus.

scholarly journals Molecular and morphological characterisation of Xiphinema granatum n. sp. and Longidorus pisi Edward, Misra & Singh, 1964 (Dorylaimida: Longidoridae) from Iran

Nematology ◽  
2012 ◽  
Vol 14 (8) ◽  
pp. 949-960 ◽  
Author(s):  
Majid Pedram ◽  
Ebrahim Pourjam ◽  
Juan E. Palomares-Rius ◽  
Razieh Ghaemi ◽  
Carolina Cantalapiedra-Navarrete ◽  
...  
Keyword(s):  
New Species ◽  
Species Group ◽  
Rrna Gene ◽  
28S Rrna ◽  
Morphometric Data ◽  
Molecular Analyses ◽  
Morphological Characterisation ◽  
28S Rrna Gene ◽  
Close Relationship ◽  
Female Genital

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.

scholarly journals Saksenaea dorisiae sp. nov., a New Opportunistic Pathogenic Fungus from Europe

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Roman Labuda ◽  
Andreas Bernreiter ◽  
Doris Hochenauer ◽  
Christoph Schüller ◽  
Alena Kubátová ◽  
...  
Keyword(s):  
Pathogenic Fungus ◽  
Elongation Factor ◽  
Its Region ◽  
Rrna Gene ◽  
28S Rrna ◽  
New Taxon ◽  
Translation Elongation ◽  
The Republic ◽  
Opportunistic Pathogenic ◽  
Continental Climate

A new species, Saksenaea dorisiae (Mucoromycotina, Mucorales), isolated from a water sample originating from a private well in Manastirica, Petrovac, in the Republic of Serbia (Europe), is described and illustrated. The new taxon is well supported by multilocus phylogenetic analysis that included the internal transcribed spacer (ITS) region, domains D1 and D2 of the 28S rRNA gene (LSU), and translation elongation factor-1α gene (tef-1α), and it is resolved in a clade with S. oblongispora and S. trapezispora. This fungus is characterized by its moderately slow growth at 15 and 37°C, sparse rhizoids, conical-shaped sporangia, and short-cylindrical sporangiospores. Saksenaea dorisiae is a member of the opportunistic pathogenic genus often involved in severe human and animal mucormycoses encountered in tropical and subtropical regions. Despite its sensitivity to several conventional antifungals (terbinafine and ciclopirox), the fungus can potentially evoke clinically challenging infections. This is the first novel taxon of the genus Saksenaea described from the moderately continental climate area of Europe.

Placement of Cacoceria and phylogenetic relationships of the xylotine genera of the tribe Milesiini (Diptera, Syrphidae: Eristalinae) based on molecular characters

Zootaxa ◽  
2006 ◽  
Vol 1171 (1) ◽  
pp. 17 ◽  
Author(s):  
GUNILLA STÅHLS
Keyword(s):  
Intraspecific Variation ◽  
Phylogenetic Relationships ◽  
Rrna Gene ◽  
28S Rrna ◽  
Large Fragment ◽  
Mitochondrial Coi ◽  
Phylogenetic Placement ◽  
28S Rrna Gene ◽  
Molecular Characters

The phylogenetic relationships of traditional xylotine genera of tribe Milesiini (Diptera, Syrphidae: Eristalinae) were explored using molecular character of a large fragment of the mitochondrial COI and the D2-3 region of the nuclear ribosomal 28S rRNA gene. Of particular interest was the phylogenetic placement of the enigmatic Neotropical genus Cacoceria. The ingroup included 48 taxa, and Cheilosia illustrata (Rhingiini, Eristalinae) was used as outgroup. Multiple specimens of more common taxa were sequenced for surveying levels of intraspecific variation. The combined dataset was analysed using parsimony and optimisation alignment, using the program POY. Cacoceria was resolved within the Chalcosyrphus clade. Earlier hypotheses placed the taxon in the tribe Myoleptini or Chrysogasterini, or in Xylotini without stating a closer relationship to any particular xylotine taxon. The representatives of traditional xylotine taxa were resolved as ((Hadromyia + (Brachypalpoides + Blera + Lejota) + (Xylota sg. Hovaxylota + Xylota sg. Sterphoides) + (Xylota (including Sterphus)) while Neplas and Brachypalpus were resolved in the Myoleptini albeit with very low support.

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