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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.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2022-04-13T19:06:35Z No. of bitstreams: 1 2019 - Camila Costa de Oliveira.pdf: 1061622 bytes, checksum: 7ce3513cc84d5e88a63c254d02e32daf (MD5) Made available in DSpace on 2022-04-13T19:06:35Z (GMT). No. of bitstreams: 1 2019 - Camila Costa de Oliveira.pdf: 1061622 bytes, checksum: 7ce3513cc84d5e88a63c254d02e32daf (MD5) Previous issue date: 2019-08-16 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 Antimicrobial resistance has emerged globally as one of the greatest threats to public health, mainly due to the widespread use of antimicrobial in humans and animal production. The use of animal manure provides benefits to the soil, besides being an alternative to the discharge of this residue in the environment, since animal production is an expressive activity of the Brazilian agribusiness. However, it can increase bacteria and antimicrobial resistance genes and promote its dissemination to commensal and pathogenic bacteria of humans and animals. Strategies to manage these residues, such as composting, are important tools to ensure the safety of their use as organic fertilizer. In this context, the aim of this study was to evaluate the presence of antimicrobial resistance genes in soils of agricultural crops treated with fresh poultry manure and legal reserve areas near these production areas in Nova Friburgo, RJ, in order to clarify the role of these environments as a reservoir and source of dissemination of antimicrobial resistance. It was also evaluated the effect of the composting process of poultry manure on the prevalence of resistance genes. After the total DNA extraction of the soil samples, the detection of the resistance genes to ?-lactamics, colistin and sulphonamides (blaampC, mcr-1, sul1 and sul2, respectively) was performed using PCR (Polymerase Chain Reaction), followed by a correlation analysis of the presence of the genes in relation to the physical-chemical attributes of soils. The relative abundance of the mcr-1 gene was determined by the qPCR (Quantitative Polymerase Chain Reaction) technique. The presence of resistance genes was also evaluated at 0, 30, 60, 90 and 120 days of poultry manure composting. There was a significant difference (P < 0.05) between the proportions of genes sul1 and sul2 in the areas of agricultural production and legal reserve, being predominant in the agricultural areas. The mcr-1 gene was detected in all soil samples. The log of relative abundance of the mcr-1 gene ranged from-1.76 (1.81 x 10-? copies of mcr-1/16S rDNA) to -3.12 (7.67 x 10-4 copies of mcr-1/16S rDNA). The blaampC gene was not detected after 30 days of composting. Otherwise, the genes sul1, sul2 and mcr-1 were detected up to 120 days of composting. These results reinforce the importance of studies that aimed at elucidating the pathways for the dissemination of antimicrobial resistance genes in agricultural production areas, as well as the factors that interfere in the persistence and dissemination of these genes in the environment, in order to subsidize the implementation of management practices that reduce the risk of spreading resistance, which is a potential threat to public health. A resist?ncia antimicrobiana tem emergido globalmente como uma das maiores amea?as para sa?de p?blica, principalmente devido ao uso generalizado de antimicrobianos em humanos e na produ??o animal. O uso de esterco animal proporciona benef?cios para o solo, al?m de ser uma alternativa para a disposi??o deste res?duo no ambiente, uma vez que a produ??o animal ? uma atividade expressiva do agroneg?cio brasileiro. Por?m, pode incrementar bact?rias e genes de resist?ncia a antimicrobianos e favorecer sua dissemina??o para bact?rias patog?nicas e comensais de humano e animais. Estrat?gias de manejo destes res?duos, como a compostagem, s?o importantes ferramentas para garantir seguridade de seu uso como fertilizante. Neste contexto, o objetivo deste trabalho foi avaliar a presen?a de genes de resist?ncia a antimicrobianos em solos de cultivos agr?colas tratados com cama de avi?rio fresca e de reserva legal pr?ximas ?s ?reas agr?colas em Nova Friburgo, RJ, a fim de elucidar o papel destes ambientes como reservat?rio e fonte de dissemina??o da resist?ncia a antimicrobianos. Foi tamb?m avaliado, o efeito do processo de compostagem da cama de avi?rio na preval?ncia de genes de resist?ncia. Ap?s a extra??o do DNA total das amostras de solo, foi realizada a detec??o dos genes de resist?ncia a ?-lact?micos, colistina e sulfonamidas (blaampC, mcr-1, sul1 e sul2, respectivamente) pela t?cnica de PCR (Polymerase Chain Reaction), seguida de uma an?lise de correla??o da presen?a dos genes em rela??o aos atributos f?sico-qu?micos dos solos. A abund?ncia relativa do gene mcr-1 foi determinada pela t?cnica de qPCR (Quantitative Polymerase Chain Reaction). A presen?a dos genes de resist?ncia tamb?m foi avaliada nos tempos 0, 30, 60, 90 e 120 dias de compostagem da cama de avi?rio. Houve diferen?a significativa (P < 0,05) entre as propor??es dos genes sul1 e sul2 nas ?reas de cultivo agr?cola e reserva legal, sendo prevalentes nas ?reas de cultivo agr?cola. O gene mcr-1 foi detectado em todas as amostras de solo. O log da abund?ncia relativa do gene mcr-1 variou de -1,76 (1,81 x 10-? c?pias de mcr-1/16S rDNA) a -3,12 (7,67 x 10-4 c?pias de mcr-1/16S rDNA). O gene blaampC n?o foi detectado ap?s 30 dias de compostagem. J? os genes sul1, sul2 e mcr-1 foram detectados at? 120 dias de compostagem. Esses resultados refor?am a import?ncia de estudos que visem elucidar as vias de dissemina??o de genes de resist?ncia a antimicrobianos nas ?reas de produ??o agr?cola, bem como os fatores que interferem na persist?ncia e dissemina??o desses genes no ambiente, a fim de subsidiar a implementa??o de pr?ticas de manejo que diminuam o risco de dissemina??o da resist?ncia, que constitui uma amea?a potencial ? sa?de p?blica.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2021-05-13T22:16:59Z No. of bitstreams: 1 2018- Carlos Vergara Torres J?nior.pdf: 4875221 bytes, checksum: 8b28f2ec44a9c94d03d3c4e72c56df4f (MD5) Made available in DSpace on 2021-05-13T22:16:59Z (GMT). No. of bitstreams: 1 2018- Carlos Vergara Torres J?nior.pdf: 4875221 bytes, checksum: 8b28f2ec44a9c94d03d3c4e72c56df4f (MD5) Previous issue date: 2018-02-20 Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES, Brasil) Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do Rio de Janeiro (FAPERJ, Brasil) A plant colonized by dark septate endophytic (DSE fungi) fungi can better recovery the nutrients provided to it when mutualistic interaction is established, generating financial savings to the farmer. However, several ecological functions of DSE fungi still need to be clarified. The present study aimed to evaluate the effect of dark septate endophytic fungi on the nitrogen recovery efficiency in tomato and rice plants and on the expression of plasma membrane H+-ATPase (PM H+-ATPase) isoforms and nitrate (NO3-) transporters in rice plants. The experiments with tomato and rice were conducted in non-sterile greenhouse soil in a randomized complete block design with five replicates. The treatments consisted of tomato (Santa Clara I-5300 variety) or rice (Piau? variety) plants without (control) and inoculated with DSE fungi A101, A104 and A105, and A101 and A103, respectively. Pots containing non-sterile material from the surface horizon of a Fragiudult soil, received ammonium sulfate enriched with 1 atom % 15N excess or finely ground Canavalia ensiformis [L.] enriched with 2.15 or 0.7 atom % 15N excess as the sole source of N. Growth plant indicators, accumulation of plant dry matter and nutrients, and recovery efficiency of 15N were evaluated at 54 days after transplanting and at maturity stage of rice plants, and at 50 days after transplanting of tomato seedlings. Expression of NO3- transporters and PM H+ -ATPase isoforms and H+ pumps activity was also evaluated in rice plants inoculated with A103. Compared with control, rice and tomato plants were more proficient in the recovery of nutrients, especially N derived from C. ensifomis. Rice plants also responded positively to the inoculation under ammonium sulfate supplementation, accumulating more dry matter and nutrients in relation to the control, and when rice plants were inoculated with the A103 fungus in a sterile environment, activity of PM H+-ATPase and of vacuolar H+-pyrophosphatase, and transcripts abundance of PM H+-ATPase isoforms OsA5 and OsA8 increased. A101, A104 and A105, and A101 and A103 fungi are beneficial for tomato and rice, respectively. Uma planta colonizada por fungos endof?ticos dark septate (fungos DSE), pode aproveitar melhor os nutrientes a ela fornecidos, quando a intera??o mutualista ? estabelecida, gerando economia financeira ao produtor. Entretanto, uma s?rie de fun??es ecol?gicas dos fungos DSE, ainda precisam ser esclarecidas. Este trabalho teve como objetivo, avaliar o efeito de fungos endof?ticos dark septate sobre a efici?ncia de aproveitamento de fontes nitrogenadas em tomate e arroz, e sobre a express?o das isoformas de H+-ATPase da membrana plasm?tica (PM H+-ATPase) e transportadores de nitrato (NO3-) em plantas de arroz. Os experimentos para estudar o efeito dos fungos DSE, na recupera??o pelas plantas do arroz e tomate do N derivado de diferentes fontes, foram conduzidos em solo n?o esterilizado, em casa de vegeta??o, em delineamento de blocos ao acaso, com cinco repeti??es. Os tratamentos consistiram de plantas de tomate (cv Santa Clara I-5300) inoculadas com os fungos DSE A101, A104 ou A105 ou de plantas de arroz (variedade Piau?) inoculadas com os fungos DSE A101 ou A103 e de plantas deixadas sem inocula??o (controle). Vasos contendo amostra de horizonte superficial de um Planossolo H?plico n?o esterilizado, receberam sulfato de am?nio marcado com 1% de ?tomos de 15N em excesso ou Canavalia ensiformis [L.] finamente triturada enriquecida com 2,15% ou 0,7 ?tomos de 15N em excesso, como ?nica fonte de N. Indicadores de crescimento, ac?mulo de mat?ria seca e nutrientes e a efici?ncia de recupera??o de 15N foram avaliados aos 54 dias ap?s o transplantio e no est?dio de matura??o do arroz (130 dias ap?s o transplantio) e aos 50 dias ap?s o transplantio de pl?ntulas de tomate. A express?o de transportadores de NO3- e isoformas PM H+-ATPase e atividade de bombas de H+ foram tamb?m avaliados em plantas de arroz inoculadas com A103, em condi??es esterilizadas. Em compara??o com o controle, as plantas de arroz e tomate foram mais eficientes no aproveitamento de nutrientes, em especial do N derivado da C. ensifomis. As plantas de arroz tamb?m responderam positivamente ? inocula??o, sob suplementa??o com sulfato de am?nio, acumulando mais mat?ria seca e nutrientes em rela??o ao controle, e quando foram inoculadas com o fungo A103 em ambiente esterilizado, aumentaram a atividade da PM H+-ATPase e da H+-pirofosfatase vacuolar e abund?ncia de transcritos das isoformas de PM H+-ATPase OsA5 e OsA8. Os fungos A101, A104 e A105 s?o ben?ficos para o tomate e os fungos A101 e A103 para o arroz.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2019-03-20T18:21:10Z No. of bitstreams: 1 2017 - Ivan de Alencar Menezes J?nior.pdf: 2048768 bytes, checksum: 10fd425fb0df338a0e4159e5c6a4d1ba (MD5) Made available in DSpace on 2019-03-20T18:21:10Z (GMT). No. of bitstreams: 1 2017 - Ivan de Alencar Menezes J?nior.pdf: 2048768 bytes, checksum: 10fd425fb0df338a0e4159e5c6a4d1ba (MD5) Previous issue date: 2017-04-27 CAPES The genus Bradyrhizobium is commonly found as endosymbiont in legumes (Fabaceae family), such as soybean (Glycine max), forming nodules on the roots and providing nitrogen from the atmosphere to these plants and to the soil. Recent research has shown the presence of bacteria from this genus inside roots of sugarcane (Saccharum spp.), a non-legume belonging to the Poaceae family. This work aims to know the population density of these bacteria associated with the roots of two sugarcane cultivars and to understand how the plant genotype (cultivar) affects the population composition of these bacteria found in the rhizosphere and the endosphere. Rhizosphere and root samples of two economically relevant sugarcane cultivars (RB867515 and IACSP95-5000) were collected in the experimental field of Embrapa Agrobiology, serially diluted and inoculated on gnotobiotic seedlings of cowpea used as trap plants. The most probable number technique was used to quantify the density of the rhizobia present in the samples and the isolates obtained from the nodules were cultivated to form pure cultures. BOX-PCR technique and sequence analysis of the ribosomal internally transcribed spacer region (ITS), recA housekeeping gene, and the symbiotic nodC gene were applied to better understand the genetic diversity of these rhizobia. Acetylene reduction test was applied to verify the presence of nitrogenase activity under free-living conditions. The presence of at least 15625 rhizobia g root -1 in rhizosphere samples and between 125 and 625 rhizobia g root-1 in the endosphere samples was observed. This shows that the density of rhizobia in the rhizosphere of sugarcane is significantly higher than in the interior of the roots for the two cane cultivars. A total of 34 isolates were obtained from the rhizosphere samples of each cultivar and 15 and 14 respectively from the roots of cultivars IACSP95-5000 and RB867515. Most of the isolates presented morphoculture characteristics of the genus Bradyrhizobium. Phylogenetic analyzes positioned most of the isolates in the superclade Bradyrhizobium elkanii. No correlation was observed between the plant cultivar and the abundance of Bradyrhizobium spp. in the roots and rhizosphere of sugarcane plants. O g?nero Bradyrhizobium ? comumente encontrado como endossimbionte em leguminosas (fam?lia Fabaceae) como a soja (Glycine max), formando n?dulos nas ra?zes dessas plantas e disponibilizando nitrog?nio da atmosfera para essas plantas e para o solo. Pesquisas recentes mostraram a presen?a de bact?rias desse g?nero no interior de ra?zes de cana-de-a??car (Saccharum spp.), uma n?o leguminosa pertencente ? fam?lia Poaceae. Este trabalho tem como objetivo conhecer a densidade populacional dessas bact?rias associadas ?s ra?zes de duas cultivares de cana-de-a??car e compreender como o gen?tipo da planta (cultivar) afeta a composi??o populacional dessas bact?rias encontradas na rizosfera e na endosfera. Amostras de rizosfera e de ra?zes de duas cultivares econ?micamente relevantes de cana-de-a??car (RB867515 e IACSP95-5000) foram coletadas no campo experimental da Embrapa Agrobiologia, seriadamente dilu?das e inoculadas em pl?ntulas gnotobi?ticas de feij?o-caupi usadas como plantas iscas. A t?cnica de n?mero mais prov?vel foi utilizada para quantificar a densidade dos riz?bios presentes nas amostras e os isolados obtidos dos n?dulos foram cultivados at? formarem culturas puras. A t?cnica de BOX-PCR e an?lise de sequ?ncia dos genes recA, regi?o ITS e nodC foram aplicadas para compreender melhor a diversidade gen?tica desses riz?bios. Ensaio de redu??o de acetileno foi aplicado para verificar a presen?a de atividade da nitrogenase. Observou-se a presen?a de no m?nimo 15625 riz?bios g -1 de raiz em amostras de rizosfera e entre 125 e 625 riz?bios g -1 de raiz nas amostras de endosfera. Isso mostra que a densidade de riz?bios na rizosfera de cana-de-a??car ? significantemente maior do que no interior das ra?zes para as duas cultivares de cana. Foram obtidos 34 isolados das amostras de rizosfera de cada cultivar e 15 e 14 respectivamente do interior das ra?zes das cultivares IACSP95-5000 e RB867515. A maior parte dos isolados apresentaram caracter?sticas morfoculturais do g?nero Bradyrhizobium. An?lises filogen?ticas posicionaram a maioria dos isolados no superclado de Bradyrhizobium elkanii. N?o foi observada correla??o entre a cultivar vegetal e a abund?ncia de Bradyrhizobium. spp. nas ra?zes e rizosfera das plantas de cana-de-a??car.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-09-13T17:03:37Z No. of bitstreams: 1 2017 - Gustavo Feitosa de Matos.pdf: 1844017 bytes, checksum: 0ed6966082e21d15123a12cd0e5777ef (MD5) Made available in DSpace on 2018-09-13T17:03:38Z (GMT). No. of bitstreams: 1 2017 - Gustavo Feitosa de Matos.pdf: 1844017 bytes, checksum: 0ed6966082e21d15123a12cd0e5777ef (MD5) Previous issue date: 2017-02-23 CNPq - Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico Recent molecular biology studies have indicated that bacteria of the genus Bradyrhizobium and Rhizobium may also play a role in the biological nitrogen fixation process (BNF) when associated with sugarcane. The use of Vigna unguiculata trap plants allowed obtaining a diverse collection of endophytic Bradyrhizobium spp. from sugarcane roots. The present work aimed to characterize a group of bacteria of the genus Bradyrhizobium from sugarcane roots, as well as to evaluate the ability of a representative strain of this group and an isolate of the genus Rhizobium to promote growth in this crop. To define the taxonomic position of the isolates of the group, phylogenetic analyzes were performed with the individual 16S rRNA, ITS, nodC and recA genes and multilocus sequence analysis (MLSA) involving four housekeeping genes (recA, dnaK, glnII and atpD), in four representative isolates (BR 10280T, BR 10266, BR 10555 and BR 10556). In addition, biochemical and morphophysiological tests were performed. Experiments in which the isolates P9-20 (BR 10280) (Bradyrhizobium sp.) and P5-2 (Rhizobium sp.) were inoculated in sugarcane seedlings were conducted in a greenhouse to evaluate the growth promoting effect of these isolates. Two harvests were performed at 30 and 75 days after transplanting (DAT). Among the analyzed variables were the budding speed index (BSI), dry mass and total nitrogen (N). Phylogenetic analyzes positioned the isolates in the superclade of B. japonicum in an independent branch close to B. huanghuaihaiense, a soybean micro-symbiont. Despite the proximity of the group under study to B. huanghuaihaiense, these isolates did not induce nodulation in Glycine max. In addition, unlike B. huanghuaihaiense, the new isolates induced nodule formation in Phaseolus vulgaris. In morphophysiological studies, significant differences were demonstrated between the representative isolates from this study and B. huanghuaihaiense. In the greenhouse experiment, an increase on BSI and root dry mass of the inoculated treatment with the P5-2 isolate was observed in the first harvest. In the second harvest, increments were found in the root dry mass and root volume, as well as in the total N of the roots and aerial part, in the treatment inoculated with P5-2, although no statistical difference was detected. These results of the characterization indicate that the sugarcane isolates of the genus Bradyrhizobium represent a new species of this genus. In relation to the greenhouse experiment, the isolate of the genus Rhizobium sp. presented potential as a growth promoter in the sugarcane crop. Estudos recentes de biologia molecular indicaram que bact?rias do g?nero Bradyrhizobium e Rhizobium tamb?m podem ter um papel no processo de fixa??o biol?gica de nitrog?nio (FBN) quando associadas ? cana-de-a??car. O uso de plantas de Vigna unguiculata como ?isca? possibilitou a obten??o de uma cole??o diversa de Bradyrhizobium spp. endof?ticos a partir de ra?zes de cana-de-a??car. O presente trabalho teve como objetivo caracterizar um grupo de bact?rias do g?nero Bradyrhizobium proveniente de ra?zes de cana-de-a??car, assim como avaliar a capacidade de uma estirpe representante desse grupo e de um isolado do g?nero Rhizobium em promover efeito de crescimento nessa cultura. Para definir o posicionamento taxon?mico dos isolados do grupo, an?lises filogen?ticas foram realizadas com os genes individuais 16S rRNA, ITS, nodC e recA e an?lise de sequ?ncia de multilocus (MLSA) envolvendo quatro genes ?housekeeping? (recA, dnaK, glnII e atpD), em quatro isolados representantes (BR 10280T, BR 10266, BR10555 e BR 10556). Al?m disso, foram realizados testes bioqu?micos e morfofisiol?gicos. Experimento onde os isolados P9-20 (BR 10280) (Bradyrhizobium sp.) e P5-2 (Rhizobium sp.) foram inoculados em minitoletes de cana-de-a??car foi conduzido em casa de vegeta??o. Foram realizadas coletas aos 30 e 75 dias ap?s transplantio (DAT). Entre as vari?veis analisadas est?o o ?ndice de velocidade de brotamento (IVB), massa seca e Nitrog?nio (N) total. An?lises filogen?ticas posicionaram os isolados no super clado de B. japonicum em um ramo independente pr?ximo a B. huanghuaihaiense, um microssimbionte de soja. Apesar da proximidade do grupo em estudo com B. huanghuaihaiense, estes isolados n?o induziram nodula??o em Glycine max. Al?m disso, diferente de B. huanghuaihaiense, os novos isolados induziram a forma??o de n?dulos em Phaseolus vulgaris. Em estudos morfofisiol?gicos foram demostradas diferen?as significativas entre os isolados representantes do grupo em estudo e B. huanghuaihaiense. Em experimento em casa de vegeta??o, observou-se na primeira coleta um incremento sobre o IVB e massa seca da raiz no tratamento inoculado com o isolado P5-2, embora n?o tenham sido observadas diferen?as estat?sticas. Na segunda coleta, incrementos foram encontrados na massa seca de raiz e volume de raiz, assim como, no N total das ra?zes e parte a?rea, no tratamento incoculado com P5-2, embora n?o tenham apresentado diferen?a estat?stica. Massa seca da parte a?rea do tratamento inoculado com P5-2 apresentou incremento na primeira e segunda coleta, em rela??o aos controles, embora n?o tenha sido detectada diferen?a estat?stica. Os resultados da caracteriza??o do grupo indicam que os isolados de cana-de-a??car do g?nero Bradyrhizobium representam uma nova esp?cie desse g?nero. Em rela??o ao experimento em casa de vegeta??o, o isolado do g?nero Rhizobium sp. apresentou potencial como promotor de crescimento na cultura de cana-de-a??car

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-23T18:13:31Z No. of bitstreams: 1 2015 - Jakson Leite.pdf: 1055808 bytes, checksum: fa105f74410a81a1f30e45ae5e911c9d (MD5) Made available in DSpace on 2017-08-23T18:13:31Z (GMT). No. of bitstreams: 1 2015 - Jakson Leite.pdf: 1055808 bytes, checksum: fa105f74410a81a1f30e45ae5e911c9d (MD5) Previous issue date: 2015-02-27 CAPES Cowpea [Vigna unguiculata (L.) Walp] is an important crop in northeastern Brazil with strategic advantages for production in semi-arid region, such its drought tolerance and good performance in low fertility soils. In addition, the nitrogen (N) fixed in symbiosis with rhizobia eliminates the demand for N fertilizers, with economic, social and environmental benefits. Little is known about the genetic diversity of bacteria associated to cowpea nodules in Brazilian semi-arid. The aim of the study was to characterize the bacterial diversity of Brazilian semi-arid soils associated with nodules of different cowpea cultivars by dependent and independent bacterial cultivation strategy. Initially a collection of 86 bacteria cowpea nodules isolated from semiarid soils was genetically characterized by partial 16S rRNA gene sequencing and symbiotic genes nifH and nodC. The sequences were compared with the NCBI database to identify isolates and phylogenetic relationships were built. In another study, we applied the independent cultivation method to evaluate bacterial communities associated with the nodules of two cowpea cultivars (BRS and BRS Acau? Pujante), in Ultisol with no history of cowpea cultivation. Nodules (N) were collected 35 days after germination, and soil samples (BS) from 0-20 cm deeper. DNA was extracted for analysis of bacterial communities with 454 pyrosequencing of the 16S ribosomal gene rRNA. The analysis of the diversity of the bacterial collection of the nodules 54 of the 86 isolates were Bradyrhizobium. Other (32) belong to Rhizobium (13) and Microvirga (1), Alfaproteobact?ria class; Burkholderia (8), and Ralstonia (1), Betaproteobacteria class; Acinetobacter (1), Cronobacter (3), Enterobacter (1), and Pantoea (1), Gamaproteobact?ria; and Leifsonia (3), phylum Actinobacteria. As Bradyrhizobium predominated, analyzes were performed with the almost full 16S rRNA, nifH and nodC and isolates were distributed in 5 lines: 16S rRNA type I (44 isolates), type II (6), Type III (1), Type IV ( 2) and type IV (1). Phylogenetic analysis of the 16S rRNA gene grouped the Type I strain in the large group Bradyrhizobium japonicum and close to the type strain of Bradyrhizobium yuanmingense. The analyses of the nifH and nodC gene separated the isolates in 5 symbiotic lines (I, II, III, IV and IV) and were congruent among them, which supports the theory of monophyletic in origin symbiotic gene Bradyhrizobium. The symbiotic lineages I and II are nearby and correspond to all isolates with 16S rRNA type I, being the dominant group associated with nodules. The partial 16S rRNA gene sequencing of bacterial communities showed high diversity in the three environments (BS, RS and N). The communities associated with the nodes were significantly different (p> 0.01) from the surrounding nodules (LS and RS). Phyla Actinobacteria, Bacteriodetes, Proteobacteria were plentiful for BS and RS. In nodes, the Proteobacteria and Bacteriodetes phyla predominated, Gammaproteobacteria being (58.8%) and Alphaproteobacteria (37.4%) in the phylum Proteobacteria and dominant Flavobacteriia (84.8%) and Sphingobacteriia (10.9%) in the phylum Bacteriodetes. For gender, Chryseobacterium, Entreobacter and Bradyrhizobium dominate in all nodes samples where Chryseobacterium prevailed in BRS Acau? and Enterobacter in BRS Pujante. O feij?o-caupi [Vigna unguiculata (L.) Walp] ? uma das principais culturas no Nordeste do Brasil com vantagens estrat?gicas para produ??o no semi?rido, como toler?ncia a seca e bom desempenho em solos de baixa fertilidade. Al?m disso, fixa N em simbiose com riz?bios eliminando a demanda de fertilizantes nitrogenados, com benef?cios econ?micos, sociais e ambientais. Pouco se sabe sobre a diversidade gen?tica de bact?rias associadas aos n?dulos de feij?o-caupi no semi?rido. O objetivo do estudo foi caracterizar a diversidade de bact?rias de solos do semi?rido brasileiro associadas aos n?dulos de diferentes cultivares de feij?o-caupi com arbordagem que depende e independe de cultivo das bact?rias. Inicialmente uma cole??o de 86 bact?rias de n?dulos de feij?o-caupi isoladas de solos do semi?rido foi caracterizada geneticamente pelo sequenciamento parcial do gene 16S rRNA e dos genes simbi?ticos nifH e nodC. As sequ?ncias foram comparadas com as do banco de dados do NCBI para identificar os isolados e as rela??es filogen?ticas dos mesmos com as de esp?cies conhecidas. Em outro estudo, aplicou-se o m?todo independente de cultivo para avaliar comunidades de bact?rias associadas aos n?dulos de dois cultivares de feij?o-caupi (BRS Pujante e BRS Acau?), em Argissolo Amarelo sem hist?rico de uso com a lavoura. Os n?dulos (N) foram coletados 35 dias ap?s a germina??o e a amostragem do solo (BS) de 0-20 cm. O DNA das amostras foi extra?do para an?lises das comunidades bacterianas com 454 pirosequenciamento do gene ribossomal 16S rRNA. Na an?lise da diversidade da cole??o de n?dulos 54 dos 86 dos isolados foram de Bradyrhizobium. Os demais (32) pertencem aos g?neros Rhizobium (13) e Microvirga (1), classe Alfaproteobact?ria; Burkholderia (8) e Ralstonia (1), classe Betaproteobact?ria; Acinetobacter (1), Cronobacter (3), Enterobacter (1) e Pantoea (1), Gamaproteobact?ria; e Leifsonia (3), filo Actinobact?ria. Como Bradyrhizobium predominou, foram feitas an?lises com os genes 16S rRNA, nifH e nodC e os isolados distribu?ram-se em 5 linhagens: 16S rRNA tipo I (44 isolados), tipo II (6), tipo III (1), tipo IV (2) e tipo IV (1). A an?lise filogen?tica do gene 16S rRNA agrupou a linhagem tipo I no grande grupo Bradyrhizobium japonicum e pr?ximo da estirpe tipo de Bradyrhizobium yuanmingense. A an?lise dos genes nifH e nodC separou os isolados em 5 linhagens simbi?ticas (I, II, III, IV e IV) e as ?rvores foram congruentes, o que suporta a teoria da origem monofil?tica de genes simbi?ticos em Bradyhrizobium. As linhagens simbi?ticas I e II s?o pr?ximas e correspondem a todos os isolados com 16S rRNA tipo I, sendo o grupo dominante associado aos nodulos. O sequenciamento parcial do gene 16S rRNA das comunidades bacterianas mostrou alta diversidade nos tr?s ambientes (BS, RS e N). As comunidades associadas aos n?dulos foram significativamente diferentes (p> 0,01) das que cercam os n?dulos (LS e RS). Os filos Actinobacteria, Bacteriodetes, Proteobacteria foram abundantes para BS e RS. Em n?dulos, os filos Proteobacteria e Bacteriodetes predominaram, sendo Gammaproteobacteria (58,8%) e Alphaproteobacteria (37,4%) dominantes no filo Proteobacteria e Flavobacteriia (84,8%) e Sphingobacteriia (10,9%) no filo Bacteriodetes. Para g?nero, Chryseobacterium, Entreobacter e Bradyrhizobium dominam em todas as amostras de n?dulos, onde Chryseobacterium predominou em BRS Acau? e Enterobacter em BRS Pujante.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2020-03-27T19:17:14Z No. of bitstreams: 1 2014 - Silvana Gomes dos Santos.pdf: 3965268 bytes, checksum: 47946032e897bb847ff7836127ac4a9c (MD5) Made available in DSpace on 2020-03-27T19:17:14Z (GMT). No. of bitstreams: 1 2014 - Silvana Gomes dos Santos.pdf: 3965268 bytes, checksum: 47946032e897bb847ff7836127ac4a9c (MD5) Previous issue date: 2014-02-24 Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES The stress of water restriction is a major constraint to the development of plants. Dark septate entophytes fungi - DSE are reported as capable of inducing tolerance to drought stress in plants. The objective of this work was to evaluate the ability of four isolates of DSE to colonize Nipponbare and Piau??s varieties of rice and promote the growth of these varieties in conditions of drought stress, in addition the evaluation of the growth of these isolates under conditions of drought stress and saline stress. The colonization?s experiment consisted of the inoculation of seeds with fungal mycelia and plants growth in tubes containing 50 ml of medium Phytagel (5g L-1) dissolved in Hoagland?s solution. To evaluate the growth of DSE in stress conditions in vitro, discs of fungal mycelium were placed in petri dishes containing BDA medium added sodium chloride (NaCl) at different concentrations and means Phytagel added polyethylene glycol 6000 (PEG). The reducing effect of DSE in stress by deficit of water in rice was evaluated by conducting two experiments. The first to evaluate the variables related to the promotion of growth (fresh and dry weight of roots and shoots and plant height) and the second, held from the pre - selection of fungi and doses of PG defined in the first trial. In the second experiment, the antioxidant enzymes related to oxidative stress were evaluated in plant catalase (CAT), ascorbate peroxidases (APX) and total protein content in leaves. The plants were grown in Phytagel (2.5 L) with Hoagland nutrient solution and plus increasing doses of PEG, and remained for 30 days under controlled temperature, humidity and photoperiod. It was observed that all isolates colonize the roots of both varieties of rice and the presence of dark septate hyphae. DSE exhibited different levels of tolerance to salinity and drought stress in vitro. The isolated Err 04 had not affected by addition of NaCl and growth was favored with the increase of water restriction in the culture medium and isolated Err 01 proved to be the most sensitive to both stresses submitted. The isolated Err 46, when in the absence of PEG, had the highest increase in height and fresh and dry weight of plants when inoculated in the variety Nipponbare. However, in the presence of -0.1 MPa water restriction the isolated Err 01 was statistically superior in all parameters and for both varieties. Significant responses, with the exception of MSR, were observed only up to the -0.2 Mpa water resistance. Inoculation of the isolated Err 01 reduced the effect of oxidative stress in plants, as evidenced by the reduction in the activity of antioxidant enzymes in almost all treatments. DSE fungi proved to be able to increase the tolerance of rice plants to drought O estresse por restri??o h?drica ? uma das mais importantes limita??es ao desenvolvimento dos vegetais. Fungos endof?ticos negros septados - DSE s?o relatados como capazes de induzir toler?ncia ao estresse h?drico em plantas. Objetivou-se atrav?s deste trabalho avaliar a capacidade de quatro isolados de DSE em colonizar as variedades de arroz Nipponbare e Piau? e promover o crescimento destas variedades em condi??o de estresse h?drico, al?m da avalia??o do crescimento destes isolados in vitro em condi??es de estresse h?drico e salino. O experimento de coloniza??o consistiu na inocula??o das sementes com mic?lio f?ngico e crescimento das plantas em tubos contendo 50 ml de meio Phytagel (5g L-1) dissolvido em solu??o de Hoagland. Para avaliar o crescimento dos DSE em condi??es de estresse in vitro depositou-se discos de mic?lio f?ngico em placas de Petri contendo meio BDA adicionado de cloreto de s?dio (NaCl) em diferentes concentra??es e em meio Phytagel adicionado de polietilenoglicol 6000 (PEG). O efeito dos DSE em reduzir o estresse por defici?ncia h?drica em arroz foi avaliado pela condu??o de 2 experimentos. O primeiro para avaliar as vari?veis relacionadas a promo??o de crescimento (massa fresca e seca da raiz e parte a?rea e altura das plantas) e o segundo, realizado a partir da pr?-sele??o dos fungos e das doses de PEG definidas no primeiro ensaio. No segundo experimento foram avaliados os teores de prote?nas totais em folhas e atividade das enzimas catalase (CAT) e ascorbato peroxidases (APX). As plantas foram cultivadas em meio Phytagel (2,5 L) com solu??o de Hoagland completa e acrescidas de doses crescentes de PEG, e permaneceram durante 30 dias em condi??es controladas de temperatura, umidade e fotoper?odo. Observou-se que todos os isolados avaliados colonizaram as ra?zes de ambas as variedades de arroz pela presen?a de hifas septadas e escuras. Os DSE apresentaram diferentes n?veis de toler?ncia ? salinidade e ao estresse h?drico in vitro. O isolado Err 04 n?o teve seu crescimento afetado pela adi??o de NaCl e foi favorecido com a o aumento da restri??o h?drica do meio de cultura e o isolado Err 01 mostrou-se o mais sens?vel a ambos os estresses submetidos. Quando inoculado o isolado Err 46 na aus?ncia do PEG apresentou maiores incrementos na altura e massas frescas e secas das plantas quando inoculado na variedade Nipponbare. No entanto, na presen?a da restri??o h?drica -0,1 Mpa o isolado Err 01 apresentou-se estatisticamente superior em todos os par?metros avaliados e em ambas ?s variedades. Respostas significativas ? inocula??o com exce??o da MSR, s? foram observadas at? a resist?ncia h?drica de -0,2 Mpa. A inocula??o do isolado Err 01 reduziu o efeito do estresse oxidativo nas plantas evidenciado pela redu??o na atividade das enzimas antioxidantes em quase todos os tratamentos. Fungos DSE mostraram capazes de aumentar a toler?ncia de plantas de arroz ao estresse por defici?ncia h?drica.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2019-08-27T17:58:03Z No. of bitstreams: 1 2014 - Carlos Vergara Torres J?nior.pdf: 4255964 bytes, checksum: 69d9e381a165eeb0cd4b059ad54dd473 (MD5) Made available in DSpace on 2019-08-27T17:58:03Z (GMT). No. of bitstreams: 1 2014 - Carlos Vergara Torres J?nior.pdf: 4255964 bytes, checksum: 69d9e381a165eeb0cd4b059ad54dd473 (MD5) Previous issue date: 2014-02-20 CAPES FAPERJ EMBRAPA Agrobiologia The dark septate endophytes (DSE) fungi can be used as plant growth promoter. However, how these fungi establish association with its host is still not fully understood. This study aimed to characterize dark septate endophytes fungi and evaluate nutrient uptake and growth of rice and tomato plants inoculated with these fungi. Using a randomized block design, DSE isolates obtained from Oryza glumaepatula were characterized for their ability to change pH of the potato-dextrose-agar (PDA) medium with bromothymol blue, as growth at different pHs (4, 5, 7 and 8), for ability to solubilize calcium phosphate and using organic and/or inorganic nutrient sources. Other assays were conducted in a growth chamber conditions and treatments consisted of rice (variety Piau?) and tomato (variety Santa Clara I- 5300) plants with and without inoculation with different DSE isolates (ERR 01, ERR 16, ERR 26 and ERR 42). In these trials were determined kinetic parameters, Vmax and KM , of NO3- uptake, NO3- - N , NH4+-N , free amino-N , soluble sugars and macronutrients contents. The results showed that the ERR 02 and ERR 04 isolates alkalized the middle and other acidified. In the test with different pHs was observed that only the growth of ERR 46 and ERR 02 fungi was not influenced by the pH ranges tested. None of the tested isolates was able to solubilize the calcium phosphate. It was also possible to observe that the ERR 04 fungi developed better in the presence of organic and/or inorganic nutrients sources, when compared to other isolates. The results of the experiment with rice showed that plants inoculated with the ERR 16 and ERR 01 fungi had a lower KM when compared to control. Moreover, in plants inoculated with the ERR 16 fungus, increases in amino-N, soluble sugars, N , P , K , Mg and S contents, fresh and dry weight of roots and shoots, height and number of tillers per plant, compared to the control. The results of the experiment with tomato showed that plants inoculated with the ERR 01 and ERR 42 fungi showed significant increases in soluble sugar, P , K , Mg and S content, dry weight of root, stem , leaf and shoot when compared to control. Furthermore, in the treatment inoculated with ERR 42 greater Vmax was observed. The study shows that the ERR 02 and ERR 46 fungi alone are not influenced by different pHs and ERR 04 fungus is promising for the tests of evaluation transfer of nutrients from the organic material to its host. Furthermore, the ERR 16 fungus shows potential to promote plant growth in rice and ERR 01 and ERR 42 fungi to tomato. Os fungos dark septate podem ser utilizados como promotores do crescimento vegetal. Contudo, a forma como estes fungos estabelecem associa??o com o seu hospedeiro ainda n?o ? totalmente compreendida. Este trabalho teve por objetivo caracterizar fungos dark septate e avaliar absor??o de nutrientes e crescimento de plantas de arroz e tomate inoculadas com estes fungos. Utilizando-se delineamento de blocos casualizados, isolados de FEDS, obtidos de Oryza glumaepatula, foram caracterizados quanto a capacidade para alterar pH do meio ?gar-batata-dextrose (BDA) com azul de bromotimol, quanto ao crescimento em diferentes pHs (4, 5, 7 e 8), quanto a capacidade para solubilizar fosfato de c?lcio e utilizar fontes org?nicas e/ou inorg?nicas de nutrientes. Outros ensaios foram conduzidos em condi??es de c?mara de crescimento e os tratamentos consistiram de plantas de arroz (variedade Piau?) e tomate (cultivar Santa Clara I-5300), com e sem inocula??o com diferentes isolados de fungos dark septate (ERR 01, ERR 16, ERR 26 e ERR 42). Nesses ensaios foram determinados os par?metros cin?ticos, Vm?x e KM, da absor??o de NO3-, teores de N-NO3-, N-NH4+, N-amino livre, a??cares sol?veis e macronutrientes. Os resultados mostraram que os fungos ERR 02 e ERR 04 alcalinizaram o meio e os demais o acidificaram. No teste com os diferentes pHs foi poss?vel observar que apenas o crescimento dos fungos ERR 02 e ERR 46 n?o foi influenciado pelas faixas de pH testadas. Nenhum dos isolados testado foi capaz de solubilizar o fosfato de c?lcio. Foi poss?vel observar ainda que o isolado ERR 04 desenvolveu-se melhor na presen?a de fontes org?nicas e/ou inorg?nicas de nutrientes, comparativamente aos demais isolados. Os resultados do experimento com arroz mostraram que as plantas inoculadas com os fungos ERR 16 e ERR 01 apresentaram um KM menor da absor??o de NO3-, comparativamente ao controle. Al?m disso, nas plantas inoculadas com o fungo ERR 16 foram observados, incrementos no conte?do de N-amino, a?ucares sol?veis, nos conte?dos de N, P, K, Mg e S, na massa fresca e seca de raiz e parte a?rea, na altura e no n?mero de perfilhos por planta, comparativamente ao controle. Os resultados do experimento com tomate mostraram que as plantas inoculadas com os fungos ERR 01 e ERR 42 apresentaram incrementos significativos nos conte?dos a??cares sol?veis, P, K, Mg e S, na massa de raiz, caule, folha e parte a?rea seca, quando comparado ao controle. Al?m disso, no tratamento inoculado com ERR 42 se observou maior Vm?x da absor??o de NO3-. O estudo mostra que os isolados ERR 02 e ERR 46 n?o s?o influenciados pelos diferentes pHs testados e que o isolado ERR 04 ? promissor para testes de avalia??o da transfer?ncia de nutrientes da mat?ria org?nica para seu hospedeiro. Al?m disso, o fungo ERR 16 apresenta potencial para a promo??o do crescimento vegetal do arroz e os fungos ERR 01 e ERR 42 para tomate.