Showing papers by "David Bass published in 2014"
Spanish National Research Council1, Pierre-and-Marie-Curie University2, Centre national de la recherche scientifique3, American Museum of Natural History4, Kaiserslautern University of Technology5, University of Nice Sophia Antipolis6, Aix-Marseille University7, University of Oslo8, Stazione Zoologica Anton Dohrn9, Tokyo Institute of Technology10, University of Geneva11, IFREMER12, University of Exeter13
TL;DR: The authors investigated abundant and rare subcommunities of marine microbial eukaryotes, a crucial group of organisms that remains among the least-explored biodiversity components of the biosphere.
375 citations
TL;DR: The authors' molecular and morphological analyses of phytomyxid isolates demonstrate two cross-kingdom host shifts between closely related parasite species: between angiosperms and oomycetes, and from diatoms/brown algae to angios perms.
Abstract: Phytomyxids (plasmodiophorids and phagomyxids) are cosmopolitan, obligate biotrophic protist parasites of plants, diatoms, oomycetes and brown algae. Plasmodiophorids are best known as pathogens or vectors for viruses of arable crops (e.g. clubroot in brassicas, powdery potato scab, and rhizomania in sugar beet). Some phytomyxid parasites are of considerable economic and ecologic importance globally, and their hosts include important species in marine and terrestrial environments. However most phytomyxid diversity remains uncharacterised and knowledge of their relationships with host taxa is very fragmentary. Our molecular and morphological analyses of phytomyxid isolates–including for the first time oomycete and sea-grass parasites–demonstrate two cross-kingdom host shifts between closely related parasite species: between angiosperms and oomycetes, and from diatoms/brown algae to angiosperms. Switching between such phylogenetically distant hosts is generally unknown in host-dependent eukaryote parasites. We reveal novel plasmodiophorid lineages in soils, suggesting a much higher diversity than previously known, and also present the most comprehensive phytomyxid phylogeny to date. Such large-scale host shifts between closely related obligate biotrophic eukaryote parasites is to our knowledge unique to phytomyxids. Phytomyxids may readily adapt to a wide diversity of new hosts because they have retained the ability to covertly infect alternative hosts. A high cryptic diversity and ubiquitous distribution in agricultural and natural habitats implies that in a changing environment phytomyxids could threaten the productivity of key species in marine and terrestrial environments alike via host shift speciation.
91 citations
TL;DR: High frequencies of haplosporidian lineages in the water column provide the first evidence for life cycles involving planktonic hosts, host-free stages or both and emphasises the importance of lineage-specific approaches for studying these highly divergent and diverse lineages.
Abstract: Haplosporidians are rhizarian parasites of mostly marine invertebrates. They include the causative agents of diseases of commercially important molluscs, including MSX disease in oysters. Despite their importance for food security, their diversity and distributions are poorly known. We used a combination of group-specific PCR primers to probe environmental DNA samples from planktonic and benthic environments in Europe, South Africa and Panama. This revealed several highly distinct novel clades, novel lineages within known clades and seasonal (spring vs autumn) and habitat-related (brackish vs littoral) variation in assemblage composition. High frequencies of haplosporidian lineages in the water column provide the first evidence for life cycles involving planktonic hosts, host-free stages or both. The general absence of haplosporidian lineages from all large online sequence data sets emphasises the importance of lineage-specific approaches for studying these highly divergent and diverse lineages. Combined with host-based field surveys, environmental sampling for pathogens will enhance future detection of known and novel pathogens and the assessment of disease risk.
64 citations
TL;DR: Two emerging diseases of juvenile crabs and oysters from the UK are investigated using massively parallel sequencing and targeted primer approaches to reveal that their causative agents are highly divergent lineages related to M. mackini and P. canceri, demonstrating that these newly recognized parasites are in fact common, diverse, and widespread and should be considered when assessing the risks of aquaculture activities, invasive species spread, and movements of ballast water and sediments.
55 citations
TL;DR: A set of 'best practice' measures, broadly based upon current taxonomic philosophies for protists and metazoans, that should be applied when defining taxa for listing as notifiable are proposed.
29 citations
Commonwealth Scientific and Industrial Research Organisation1, American Museum of Natural History2, University of California, Davis3, University of Arizona4, University of Edinburgh5, Australian National University6, Ghent University7, New York University8, University of Geneva9, University of Colorado Boulder10, Imperial College London11, University of New Hampshire12, Bangor University13
TL;DR: High-throughput sequencing of DNA marker genes recovered from environmental samples (known as ecogenomics or metabarcoding) is an emerging tool for understanding patterns and processes in ecology and biodiversity.
Abstract: High-throughput sequencing of DNA marker genes recovered from environmental samples (known as ecogenomics or metabarcoding) is an emerging tool for understanding patterns and processes in ecology and biodiversity [[1][1]]. The recent paper ‘Are there species smaller than 1 mm?’ [[2][2]] was
15 citations
TL;DR: It is concluded that fungal communities associated with ancient semi- natural woodland also exist on sites converted to non-native conifer plantations, and attempts to restore native, semi-natural woodland may have an increased chance of success when focussed on restoration of plantations, rather than the creation of new woodland on ex-agricultural land.
Abstract: The restoration of microbial communities may be central to the re-establishment of plant–soil interactions and renovation of function in degraded woodland systems. However, there is currently little knowledge of the extent to which the soil microbial communities associated with past vegetation persist in such systems. This study used fungal-specific internal transcribed spacer (ITS) ribosomal DNA environmental clone libraries to compare fungal communities in four ancient semi-natural woodland sites in the UK with adjacent non-native conifer plantations, and with adjacent grassland. In total, we recovered 190 distinct ITS sequence types (ITS types), of which the greatest diversity occurred in ancient semi-natural woodland. Although ancient semi-natural woodland and adjacent conifer plantations shared 27 ITS types, none were shared between woodland and grassland sites. A total of 16 ectomycorrhizal genera were subsequently identified using BLASTn searches, of which nine were recovered from both woodland types and none were shared between woodland and grassland sites. Only eight of these genera had previously been identified from sporophores during 50 years of surveying carried out at the same woodland sites. We conclude that fungal communities associated with ancient semi-natural woodland also exist on sites converted to non-native conifer plantations. In consequence, attempts to restore native, semi-natural woodland may have an increased chance of success when focussed on restoration of plantations, rather than the creation of new woodland on ex-agricultural land.
7 citations
01 Jan 2014
TL;DR: Noise obscures the genetic signal of meiobiotal ecospecies inecogenomic datasets because of noise, according to Morgan MJ and colleagues.
Abstract: Cite this article: Morgan MJ et al. 2014 Acritique of Rossberg et al.: noise obscures thegenetic signal of meiobiotal ecospecies inecogenomic datasets. Proc. R. Soc. B 281:20133076.http://dx.doi.org/10.1098/rspb.2013.3076Received: 24 November 2013Accepted: 23 December 2013Authors for correspondence:M. J. Morgane-mail: matthew.morgan@csiro.auS. Creere-mail: s.creer@bangor.ac.ukThe accompanying reply can be viewed athttp:/dx.doi.org/doi:10.1098/rspb.2014.0191.Electronic supplementary material is availableat http://dx.doi.org/10.1098/rspb.2013.3076 orvia http://rspb.royalsocietypublishing.org.