title: High Diversity Revealed in Leaf-Associated Protists (Rhizaria: Cercozoa) of Brassicaceae.
abstract: The largest biological surface on earth is formed by plant leaves. These leaf surfaces are colonized by a specialized suite of leaf-inhabiting microorganisms, recently termed "phyllosphere microbiome". Microbial prey, however, attract microbial predators. Protists in particular have been shown to structure bacterial communities on plant surfaces, but virtually nothing is known about the community composition of protists on leaves. Using newly designed specific primers targeting the 18S rDNA gene of Cercozoa, we investigated the species richness of this common protist group on leaves of four Brassicaceae species from two different locations in a cloning-based approach. The generated sequences revealed a broad diversity of leaf-associated Cercozoa, mostly bacterial feeders, but also including known plant pathogens and a taxon of potential endophytes that were recently described as algal predators in freshwater systems. This initial study shows that protists must be regarded as an integral part of the microbial diversity in the phyllosphere of plants.
authors.affiliation: Institute of Population Genetics, Cluster of Excellence in Plant Sciences, University of Düsseldorf, Universitätsstr. 1, D-40225, Düsseldorf, Germany.|Senckenberg Biodiversity and Climate Research Center, Georg-Voigt-Street 14-16, D-60325, Frankfurt, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Ploch
authors.affiliation: Institute of Population Genetics, Cluster of Excellence in Plant Sciences, University of Düsseldorf, Universitätsstr. 1, D-40225, Düsseldorf, Germany.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Rose
authors.affiliation: Department of Life Sciences, The Natural History Museum, London, SW7 5BD, United Kingdom.|Centre for Environment, Fisheries, and Aquaculture Science (Cefas), Barrack Road, The Nothe, Weymouth, Dorset, DT4 8UB, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Bass
authors.affiliation: Department of Terrestrial Ecology, Institute of Zoology, University of Cologne, Zülpicher Street 47b, D-50674, Köln, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bonkowski
mesh_terms: D000818:Animals; D001419:Bacteria; D001483:Base Sequence; D044822:Biodiversity; D019607:Brassicaceae / Q000145:classification / Q000382:microbiology / Q000469:parasitology*; D056907:Cercozoa / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D002965:Classification; D016054:DNA, Protozoan; D004275:DNA, Ribosomal / Q000235:genetics; D056890:Eukaryota / Q000145:classification / Q000235:genetics; D019143:Evolution, Molecular; D005618:Fresh Water / Q000469:parasitology; D005858:Germany; D010802:Phylogeny; D010935:Plant Diseases / Q000469:parasitology; D018515:Plant Leaves / Q000382:microbiology / Q000469:parasitology*; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D056901:Rhizaria / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S
keywords: 18S; Arabidopsis; Cercomonas; cloning; environmental sequencing; phyllosphere; protist