title: A NOVEL EPIPHYTIC CYANOBACTERIAL SPECIES FROM THE GENUS BRASILONEMA CAUSING DAMAGE TO EUCALYPTUS LEAVES(1).
abstract: A cyanobacterial mat colonizing the leaves of Eucalyptus grandis was determined to be responsible for serious damage affecting the growth and development of whole plants under the clonal hybrid nursery conditions. The dominant cyanobacterial species was isolated in BG-11 medium lacking a source of combined nitrogen and identified by cell morphology characters and molecular phylogenetic analysis (16S rRNA gene and cpcBA-IGS sequences). The isolated strain represents a novel species of the genus Brasilonema and is designated Brasilonema octagenarum strain UFV-E1. Thin sections of E. grandis leaves analyzed by light and electron microscopy showed that the B. octagenarum UFV-E1 filaments penetrate into the leaf mesophyll. The depth of infection and the mechanism by which the cyanobacterium invades leaf tissue were not determined. A major consequence of colonization by this cyanobacterium is a reduction in photosynthesis in the host since the cyanobacterial mats decrease the amount of light incident on leaf surfaces. Moreover, the cyanobacteria also interfere with stomatal gas exchange, decreasing CO2 assimilation. To our knowledge, this is the first report of an epiphytic cyanobacterial species causing damage to E. grandis leaves.
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Rosane
authors.initials: R
authors.lastname: Aguiar
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Marli Fatima
authors.initials: MF
authors.lastname: Fiore
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Maione Wittig
authors.initials: MW
authors.lastname: Franco
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Marília Contin
authors.initials: MC
authors.lastname: Ventrella
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Adriana Sturion
authors.initials: AS
authors.lastname: Lorenzi
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Cláudia A
authors.initials: CA
authors.lastname: Vanetti
authors.affiliation: Plant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilPlant Biology Department, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilCenter for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, BrazilMicroscopy & Microanalysis Center, Federal University of Viçosa, Viçosa, Minas Gerais, BrazilPlant Pathology Department, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Acelino Couto
authors.initials: AC
authors.lastname: Alfenas
keywords: Brasilonema; Eucalyptus grandis; cyanobacteria; leaf anatomy; novel species; ultrastructure