title: 'Candidatus Phytoplasma pini', a novel taxon from Pinus silvestris and Pinus halepensis.
abstract: Pinus silvestris and Pinus halepensis trees grown in Germany and Spain, respectively, showing abnormal shoot branching, dwarfed needles and other symptoms were examined for the presence of plant-pathogenic mollicutes (phytoplasmas). While phytoplasmas could not be detected unambiguously with microscopical methods, PCR amplification using universal phytoplasma primers yielded positive results. Samples collected from symptomatic and non-symptomatic plant parts of both symptomatic Pinus silvestris and Pinus halepensis trees tested positive. Also, surrounding non-symptomatic trees proved to be phytoplasma-infected. Comparisons revealed that the 16S rRNA gene sequences of the phytoplasmas identified in Pinus silvestris and Pinus halepensis were nearly identical. However, the pine phytoplasma is only distantly related to other phytoplasmas. The closest relatives are members of the palm lethal yellowing and rice yellow dwarf groups and 'Candidatus Phytoplasma castaneae', which share between 94.5 and 96.6 % 16S rRNA gene sequence similarity. From these data it can be concluded that the phytoplasmas identified in the two Pinus species represent a coherent but discrete taxon; it is proposed that this taxon be distinguished at putative species level under the name 'Candidatus Phytoplasma pini'.
authors.affiliation: Biologische Bundesanstalt für Land- und Forstwirtschaft, Institut für Pflanzenschutz im Obstbau, D-69211 Dossenheim, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Schneider
authors.affiliation: Laboratori Sanitat Vegetal, Generalitat de Catalunya, Barcelona, Spain.
authors.forename: Ester
authors.initials: E
authors.lastname: Torres
authors.affiliation: Real Jardín Botánico, CSIC, Madrid, Spain.
authors.forename: María P
authors.initials: MP
authors.lastname: Martín
authors.affiliation: Landesanstalt für Pflanzenschutz, D-70197 Stuttgart, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Schröder
authors.affiliation: Universität Heidelberg, Heidelberger Institut für Pflanzenwissenschaften, D-69120 Heidelberg, Germany.
authors.forename: Heinz-Dietmar
authors.initials: HD
authors.lastname: Behnke
authors.affiliation: Biologische Bundesanstalt für Land- und Forstwirtschaft, Institut für Pflanzenschutz im Obstbau, D-69211 Dossenheim, Germany.
authors.forename: Erich
authors.initials: E
authors.lastname: Seemüller
mesh_terms: D004269:DNA, Bacterial / Q000032:analysis; D021903:DNA, Ribosomal Spacer / Q000032:analysis; D020459:Genes, rRNA; D008969:Molecular Sequence Data; D010802:Phylogeny; D045582:Phytoplasma / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D028223:Pinus / Q000382:microbiology*; D041605:Pinus sylvestris / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S