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The strain BR 3262 was isolated from nodule of cowpea (Vigna unguiculata L. Walp) growing in soil of the Atlantic Forest area in Brazil and it is reported as an efficient nitrogen fixing bacterium associated to cowpea. Firstly, this strain was assigned as Bradyrhizobium elkanii, however, recently a more detailed genetic and molecular characterization has indicated it could be a Bradyrhizobium pachyrhizi species. We report here the draft genome sequence of B. pachyrhizi strain BR 3262, an elite bacterium used as inoculant for cowpea. The whole genome with 116 scaffolds, 8,965,178 bp and 63.8% of C+G content for BR 3262 was obtained using Illumina MiSeq sequencing technology. Annotation was added by the RAST prokaryotic genome annotation service and shown 8369 coding sequences, 52 RNAs genes, classified in 504 subsystems.

Submitted by Jonathan Barbosa (jon_crf@hotmail.com) on 2012-02-28T12:38:57Z No. of bitstreams: 1 Cardoso_2010.pdf: 1104505 bytes, checksum: d4410cb16dc3c98dd11d861075414e5c (MD5) Rejected by Catarina Soares(cfsoares@inmetro.gov.br), reason: Corrigir nomes dos autores na referencia bibliografica on 2012-03-15T18:22:37Z (GMT) Submitted by Jonathan Barbosa (jon_crf@hotmail.com) on 2012-03-16T12:36:30Z No. of bitstreams: 1 Cardoso_2010.pdf: 1104505 bytes, checksum: d4410cb16dc3c98dd11d861075414e5c (MD5) Approved for entry into archive by Regina Mello(mrmello@inmetro.gov.br) on 2012-06-26T17:21:40Z (GMT) No. of bitstreams: 1 Cardoso_2010.pdf: 1104505 bytes, checksum: d4410cb16dc3c98dd11d861075414e5c (MD5) Made available in DSpace on 2012-06-27T17:59:07Z (GMT). No. of bitstreams: 1 Cardoso_2010.pdf: 1104505 bytes, checksum: d4410cb16dc3c98dd11d861075414e5c (MD5) Previous issue date: 2010 Background: Gluconacetobacter diazotrophicus Pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. It has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins. Results: Gluconacetobacter diazotrophicus Pal5 is the third diazotrophic endophytic bacterium to be completely sequenced. Its genome is composed of a 3.9 Mb chromosome and 2 plasmids of 16.6 and 38.8 kb, respectively. We annotated 3,938 coding sequences which reveal several characteristics related to the endophytic lifestyle such as nitrogen fixation, plant growth promotion, sugar metabolism, transport systems, synthesis of auxin and the occurrence of bacteriocins. Genomic analysis identified a core component of 894 genes shared with phylogenetically related bacteria. Gene clusters for gum-like polysaccharide biosynthesis, tad pilus, quorum sensing, for modulation of plant growth by indole acetic acid and mechanisms involved in tolerance to acidic conditions were identified and may be related to the sugarcane endophytic and plant-growth promoting traits of G. diazotrophicus. An accessory component of at least 851 genes distributed in genome islands was identified, and was most likely acquired by horizontal gene transfer. This portion of the genome has likely contributed to adaptation to the plant habitat. Conclusion: The genome data offer an important resource of information that can be used to manipulate plant/bacterium interactions with the aim of improving sugarcane crop production and other biotechnological applications. 17 p. : il.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2022-09-27T12:38:21Z No. of bitstreams: 1 Sueide Karina da Silva.pdf: 44277941 bytes, checksum: 5c6a9558edcba5ee36369d6f5c8326f5 (MD5) Made available in DSpace on 2022-09-27T12:38:21Z (GMT). No. of bitstreams: 1 Sueide Karina da Silva.pdf: 44277941 bytes, checksum: 5c6a9558edcba5ee36369d6f5c8326f5 (MD5) Previous issue date: 2022-08-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Rhizobia are bacteria known to infect legume roots, forming nodules, where these organisms can fix atmospheric nitrogenmore efficiently than the diazotrophic bacteria that colonize grasses. Several works report the presence of rhizobia inside the roots of grasses, as well as occur in sugarcane. It is not known whether these organisms have beneficial functions for plants, but if they can act as growth-promoting bacteria, the association with grassy rhizobia may represent a great possibility for the development of technologies based on bioinputs, or on more independent management of chemical fertilizers for the culture. The results obtained so far suggest that rhizobia and other non-nodulating bacteria phylogenetically related to them represent a group of microorganisms that should be better studied, regarding their application to cultures of the Poaceae family. The objective of this work was to prospect and characterize populations of rhizobia associated with the most used variety of sugarcane in Northeast Brazil, cultivated in soil with a long history of sugarcane exploitation, and to evaluate the effect of intercropping with nodulating legumes on these populations, through isolation, followed by genetic and functional characterization. An experiment was set up in the municipality of Carpina-PE, Zona da Mata de Pernambuco. The treatments were distributed in randomized blocks with four replications, representing by single crop and the intercropping of sugarcane with different species of grain-producing legumes (cowpea, peanut, and soybean). At 5 months after sugarcane planting, non-lignified roots were collected, which were macerated in saline solution and the suspension product was used as an inoculant in bait plant trials, using the same legumes of the consortia. The isolates obtained from the formed nodules were genetically characterized, through 16S rRNA sequencing, and phenotypically in YMA medium. The isolates were tested for their ability to promote growth and biomass production and to change morphoanatomical parameters of sugarcane roots, in a pre-sprouted seedling inoculation experiment of legume growth in a greenhouse experiment. In the first trial with bait plants, nodules were only formed in cowpea inoculated with the suspension prepared from the roots of sugarcane cultivated in consortium with that legume. Results indicated the lack of rhizobia populations capable of nodulating soybeans and peanuts in sugarcane tissues, as well as demonstrating that cowpea cultivation was necessary to stimulate the presence of their microsymbionts in grass roots, probably by stimulating populations naturally established into the soil. These nodules generated a collection of 20 authenticated rhizobia, with low phenotypic and genetic diversity, with 4 isolates classified as Bradyrhizobium and 7 as Rhizobium. Among all the isolates in the collection, 55% solubilized calcium phosphate and all were capable of producing AIA. The thickness of the canopy, cortex, and vascular system, as well as the density and length of root hairs in the sugarcane root were positively influenced by inoculation. Rizóbios são bactérias conhecidas por infectar raízes de leguminosas, formando nódulos onde fixam o N atmosférico de maneira mais eficiente que as bactérias diazotróficasque colonizam as gramíneas. Diversos trabalhos relatam a presença de rizóbios no interior das raizes de gramíneas, assim como a cana-de-açúcar. Não se sabe se esses organismos exercem funções benéficas para as plantas, mas, se forem capazes de atuar como bactérias promotoras de crescimento, essa associação rizóbios-gramíneas pode representar uma possibilidade de desenvolvimento de tecnologias baseadas em bioinsumos, ou em manejos mais independentes de fertilizantes químicos. Os resultados obtidos até o momento sugerem que rizóbios e outras bactérias não nodulantes filogeneticamente relacionadas com eles representam um grupo de micro-organismos que deve ser mais bem estudado no sentido da sua aplicação para culturas da família Poaceae. O objetivo deste trabalho foi prospectar e caracterizar populações de rizóbios associados à variedade de cana-de-açúcar RB 92579, a mais utilizada no Nordeste do Brasil, cultivada em solo com longo histórico de exploração canavieira, e avaliar o efeito do consórcio dessa gramínea com leguminosas nodulantes sobre essas populações, por meio de isolamento, seguido de caracterização genética e funcional. Foi montado um experimento no município de Carpina-PE, Zona da Mata de Pernambuco, com tratamentos distribuídos em blocos casualizados com quatro repetições, representando o cultivo solteiro e o consórcio da cana-de-açúcar com diferentes espécies de leguminosas produtoras de grãos (feijão-caupi, amendoim e soja). Aos 5 meses após o plantio da cana foi realizada a coleta de raízes jovens, que foram maceradas em solução salina, onde o produto suspenso foi utilizado como inoculante em ensaios de plantas iscas, utilizando as mesmas leguminosas dos consórcios. Os isolados obtidos a partir dos nódulos formados foram caracterizados geneticamente, por meio do sequenciamento do 16S rRNA, e fenotipicamente em meio Yeast mannitol agar (YMA). Os isolados foram testados quanto à capacidade de promoção de crescimento, produção de biomassa e de alterar parâmetros morfoanatômicos de raízes da cana-de-açúcar, em experimento de inoculação de mudas pre-brotadas. Também foi testada a capacidade dos isolados em promover a promoção de crescimento de leguminosas, em experimento em casa de vegetação. No primeiro ensaio com plantas-iscas, só houve formação de nódulos em feijão-caupi inoculado com a suspensão preparada a partir das raízes de cana cultivada em consórcio com esta leguminosa. Este resultado indica a inexistência de populações de rizóbios com capacidade de nodular a soja e o amendoim nos tecidos da cana, além da necessidade do cultivo do feijão-caupi para estimular a presença de seus microssimbiontes nas raízes da gramínea, provavelmente por estimular as populações naturalmente estabelecidas no solo. Esses nódulos geraram uma coleção de 20 rizóbios autenticados, com baixa diversidade fenotípica e genética, sendo 4 isolados classificados como Bradyrhizobium e 7 como Rhizobium. Entre todos os isolados da coleção, 55% solubilizaram fosfato de cálcio e todos foram capazes de produzir ácido indolacético. A espessura do velame, do córtex e do sistema vascular, bem como a densidade e comprimento de pêlos radiculares da raiz da cana-deaçúcar foram influenciados positivamente com a inoculação. Dessa forma, a inoculação com rizóbios provenientes de raiz de cana-de-açúcar é promissora para um cultivo mais sustentável da cana-de-açúcar.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2022-10-18T17:54:16Z No. of bitstreams: 1 2021 - J?lia Ferreira Xavier.pdf: 1751247 bytes, checksum: ad39303a61045be0a5da3f507089b30a (MD5) Made available in DSpace on 2022-10-18T17:54:16Z (GMT). No. of bitstreams: 1 2021 - J?lia Ferreira Xavier.pdf: 1751247 bytes, checksum: ad39303a61045be0a5da3f507089b30a (MD5) Previous issue date: 2021-10-08 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior CNPq - Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico FAPERJ - Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do Rio de Janeiro Most plant species, especially crops, do not tolerate high salt concentrations. However, halophytic plants are adapted to saline soils. In the rhizosphere of these plants, associations with microorganisms can promote plant growth and increase resistance to salt stress. Therefore, this work aimed to isolate and identify bacteria from the rhizosphere of halophyte plants from different saline environments in the state of Rio de Janeiro and to evaluate their capacity to promote growth of rice. Samples of rhizospheric soils from halophytic plants Salicornia gaudicahudiana, Salicornia fruticosa, Blutaparon portulacoides, Sporobolus virginucus, and Cyperus ligularis were collected. Culture media amended with 1%, 5%, 15%, 20%, and 25% of NaCl were used for bacterial isolation. The bacterial strains were classified according to growth at different NaCl concentrations and were identified by Matrix Assisted Laser Desorption Ionization Time Of Flight/ Mass Spectrometry (MALDI-TOF MS) and by rrs gene sequencing. Subsequently, the potential of nine strains of halotolerant bacteria belonging to the genus Pseudomonas and Bacillus in promoting rice growth at concentrations of 50 mM and 200 mM was analyzed. Thus, germination percentage, total root length, root volume, root surface area, number of tips, and total shoot length were analyzed. A total of 315 bacteria classified as non-halophilic (99/315), halotolerant (171/315) and moderately halophilic (32/315) were isolated. Of the isolated bacteria, 286 were analyzed by the proteomic technique MALDI-TOF MS and classified at the genus level 57% (165/286). For those that could not be identified by MALDI TOF-MS, selected isolates were identified by 16S rRNA gene (rrs) gene sequencing. The inference of the genus and/or species was possible in 97.7% (42/43) of the isolates. The most abundant genera identified were Pseudomonas, Ochrobactrum, and Bacillus. At the optimal salt concentration of 50 mM NaCl, the isolates P51 and P164, belonging to the genera Pseudomonas, provided an increase in most parameters related to rice seed germination analyzed, as compared to the non-inoculated treatment. Isolates B231, B67, and B143 related to the genus Bacillus promoted root elongation and a higher number of tips. At the stressing concentration of 200 mM, isolates B231 and B294, related to Bacillus provided an increase in the total length of roots compared to the non-inoculated treatment. These results confirm that the rhizosphere of halophyte plants represents a promising environment for the isolation of halotolerant and halophilic bacteria and that halotolerant bacteria from the genera Pseudomonas and Bacillus can promote the germination and initial development of rice seeds in the presence or absence of salt stress. A maioria das esp?cies vegetais, principalmente culturas agr?colas, n?o toleram altas concentra??es de sais. No entanto, plantas do grupo hal?fitas s?o adaptadas a solos salinos. Na rizosfera das plantas hal?fitas ocorrem associa??es com microrganismos que auxiliam o crescimento vegetal aumentando a resist?ncia ao estresse salino. Desse modo, o objetivo do trabalho foi isolar e identificar bact?rias da rizosfera de plantas hal?fitas de diferentes ambientes salinos no estado do Rio de Janeiro e avaliar sua capacidade de promo??o de germina??o e crescimento de sementes de arroz. Foram coletadas amostras de solos rizof?ricos das plantas hal?fitas Salicornia gaudicahudiana, Salicornia fruticosa, Blutaparon portulacoides, Sporobolus virginucus e Cyperus ligularis encontradas em ambientes costeiros, como mangue e salinas. Para o isolamento das bact?rias foram utilizados meios de cultura acrescidos de 1%, 5%, 15%, 20% e 25% de NaCl. As bact?rias isoladas foram classificadas de acordo o crescimento em diferentes concentra??es NaCl e foram identificadas pela t?cnica Matrix Assisted Laser Desorption Ionization Time Of Flight/ Mass Spectrometry (MALDI-TOF MS) e pelo sequenciamento do gene rrs que codifica o rRNA 16S. Foi avaliado o potencial de promo??o de crescimento do arroz na concentra??o de 50 mM e 200 mM de NaCl de nove estirpes de bact?rias halotolerantes pertencentes aos g?neros Pseudomonas e Bacillus. Foram analisados a porcentagem de germina??o, o comprimento total da raiz, volume da raiz, superf?cie de contato radicular, n?mero de ?pices e comprimento total da parte a?rea. Foram isoladas um total de 315 bact?rias classificadas como n?o halof?licas (99/315), halotolerantes (171/315) e halof?licas moderadas (32/315). Destas, 286 foram analisadas pela t?cnica prote?mica MALDI-TOF MS, sendo 57% (165/286) identificadas em n?vel seguro para g?nero. Dentre as bact?rias n?o identificadas pela t?cnica MALDI TOF-MS, foram selecionados isolados halotolerantes e halof?licos moderados para a identifica??o pelo sequenciamento do gene rrs. A infer?ncia do g?nero foi poss?vel em 97,7% (42/43) dos isolados. Os g?neros mais abundantes identificados foram Pseudomonas, Ochrobactrum e Bacillus. Na concentra??o de 50 mM de NaCl, que se mostrou ideal para a germina??o das sementes de arroz, os isolados P51 e P164, relacionadas ao g?nero Pseudomonas, proporcionaram aumento da maioria dos par?metros analisados em compara??o ao tratamento n?o inoculado. Nessa concentra??o, os isolados B231, B67 e B143, pertencentes ao g?nero Bacillus, promoveram alongamento radicular e maior n?mero de ?pices. J? a 200 mM, concentra??o inibit?ria do processo germinativo, os isolados B231 e B294, pertencentes ao g?nero Bacillus, proporcionaram aumento no comprimento total das ra?zes em compara??o ao tratamento n?o inoculado. Estes resultados confirmam que a rizosfera de plantas hal?fitas representa um ambiente promissor para o isolamento de bact?rias halotolerantes e halof?licas, e que isolados de Pseudomonas e Bacillus halolerantes podem promover o crescimento de plantas de arroz na presen?a ou aus?ncia de estresse salino.