title: Diversity and distribution of the endophytic bacterial community at different stages of Eucalyptus growth.
abstract: The relationships between plants and endophytic bacteria significantly contribute to plant health and yield. However, the microbial diversity in leaves of Eucalyptus spp. is still poorly characterized. Here, we investigated the endophytic diversity in leaves of hybrid Eucalyptus grandis x E. urophylla (Eucalyptus "urograndis") by using culture-independent and culture-dependent approaches, to better understand their ecology in leaves at different stages of Eucalyptus development, including bacteria with N2 fixation potential. Firmicutes, Proteobacteria (classes alpha-, beta- and gamma-) and Actinobacteria were identified in the Eucalyptus "urograndis" endophytic bacterial community. Within this community, the species Novosphingobium barchaimii, Rhizobium grahamii, Stenotrophomonas panacihumi, Paenibacillus terrigena, P. darwinianus and Terrabacter lapilli represent the first report these bacteria as endophytes. The diversity of the total endophytic bacteria was higher in the leaves from the 'field' (the Shannon-Wiener index, 2.99), followed by the indices obtained in the 'clonal garden' (2.78), the 'recently out from under shade (2.68), 'under shade' (2.63) and 'plants for dispatch' (2.51). In contrast, for diazotrophic bacteria, the highest means of these indices were obtained from the leaves of plants in the 'under shade' (2.56), 'recently out from under shade (2.52)' and 'field' stages (2.54). The distribution of the endophytic bacterial species in Eucalyptus was distinct and specific to the development stages under study, and many of the species had the potential for nitrogen fixation, raising the question of whether these bacteria could contribute to overall nitrogen metabolism of Eucalyptus.
authors.affiliation: Departamento de Microbiologia/Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Paulo Sérgio Balbino
authors.initials: PS
authors.lastname: Miguel
authors.affiliation: Departamento de Ciências Básicas da Vida, Universidade Federal de Juiz de Fora, Campus Governador Valadares, Juiz de Fora, MG, 36570-000, Brazil.
authors.forename: Marcelo Nagem Valério
authors.initials: MN
authors.lastname: de Oliveira
authors.affiliation: Coordenação geral de Ensino e Extensão, Instituto Federal do Triângulo Mineiro, Ituiutaba, MG, 38035-200, Brazil.
authors.forename: Júlio César
authors.initials: JC
authors.lastname: Delvaux
authors.affiliation: Celulose Nipo-Brasileira (CENIBRA), Belo Oriente, MG, 35196-000, Brazil.
authors.forename: Guilherme Luiz
authors.initials: GL
authors.lastname: de Jesus
authors.affiliation: Departamento de Microbiologia/Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Arnaldo Chaer
authors.initials: AC
authors.lastname: Borges
authors.affiliation: Departamento de Microbiologia/Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Marcos Rogério
authors.initials: MR
authors.lastname: Tótola
authors.affiliation: Departamento de solos, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Júlio César Lima
authors.initials: JC
authors.lastname: Neves
authors.affiliation: Departamento de Microbiologia/Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil. madcosta@ufv.br.
authors.forename: Maurício Dutra
authors.initials: MD
authors.lastname: Costa
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D044822:Biodiversity; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004463:Ecology; D060026:Endophytes / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D005052:Eucalyptus / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology*; D009586:Nitrogen Fixation; D010802:Phylogeny; D018515:Plant Leaves / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S
keywords: DGGE; Diversity; Endophytic bacteria; Eucalyptus development stages; Sequencing