Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-09T10:11:25Z No. of bitstreams: 1 2014 - Joel Quintino de Oliveira Junior.pdf: 986333 bytes, checksum: 680ec4322bce52cb9979155c6978ea36 (MD5) / Made available in DSpace on 2017-01-09T10:11:25Z (GMT). No. of bitstreams: 1 2014 - Joel Quintino de Oliveira Junior.pdf: 986333 bytes, checksum: 680ec4322bce52cb9979155c6978ea36 (MD5) Previous issue date: 2014-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Leguminosae comprises a wide variety of species that form symbiosis with mycorrhizal fungi (AMF), and mostly with nitrogen fixing bacteria. Within this frame fits the group Pitadenia encompassing genres: Mimosa , Piptadenia , Parapiptadenia , Anadenathera , Pseudopiptadenia , Microlobius , Stryphnodendron and Adenopia , comprising over 500 species, of which most are found in the New World , especially in Brazil . Their habits vary from tree and herbaceous species to thrive in flooded, dry, high altitude grasslands , savanna ecosystems among other areas . Are well known and used in the rehabilitation of degraded soils by their aggressiveness and ability to grow under adverse soil conditions. Results indicate that in some species of this group only nodulated with the presence of mycorrhizal fungi. Legumes use for the realization of these two symbioses very similar molecular mechanisms and some of leguminous species from the subfamily Mimosoideae show atypical and high potential exploration of evolutionary symbiosis between the two skills. The objective of this work is to investigate and confirm this dependence of the presence of arbuscular mycorrhizal fungi for nodulation and nitrogen fixation in species group Piptadenia nodulated by Burkholderia sp . under controlled conditions / A fam?lia Leguminosae compreende um imensa variedade de esp?cies que formam simbiose com fungos micorr?zicos arbusculares (FMAs) e, em sua grande maioria, com bact?rias fixadoras de nitrog?nio. Dentro desse quadro se encaixa o grupo de Pitadenia que engloba os g?neros: Mimosa, Piptadenia, Parapiptadenia, Anadenathera, Pseudopiptadenia, Microlobius, Stryphnodendron e Adenopia, compreendendo mais de 500 esp?cies, sendo que a maioria delas ? encontrada no novo mundo, em especial no Brasil. Seus h?bitos variam desde esp?cies herb?ceas at? arb?reas e se desenvolvem em ?reas alagadas, secas, campos de altitude, cerrado entre outros ecossistemas. S?o bem conhecidas e utilizadas na reabilita??o de solos degradados por sua agressividade e capacidade de se desenvolver nas mais adversas condi??es ed?ficas. Resultados indicam que em algumas esp?cies desse grupo s? nodulariam com a presen?a de fungos micorr?zicos. As leguminosas usam para a realiza??o dessas duas simbioses mecanismos moleculares muito similares e algumas dessas esp?cies de leguminosas nativas da subfam?lia Mimosoideae mostram habilidades at?picas e com alto potencial de explora??o evolucion?ria entre as duas simbioses. O objetivo deste trabalho ? investigar e confirmar essa depend?ncia da presen?a de fungos micorr?zicos arbusculares para a nodula??o e fixa??o biol?gica de nitrog?nio em esp?cies do grupo de Piptadenia noduladas por Burkholderia sp. sob condi??es controladas

Os modelos de evolução de vias metabólicas estão baseados em técnicas moleculares e bioinformática e nem sempre levam em consideração o contextos fisiológico e ecológico do organismo. Assim, tomando como plataforma o metabolismo de nitrogênio, procurou-se estabelecer uma hipótese evolutiva para o uso de α-aminoácidos por metazoários como fonte de nitrogênio. O objetivo é traçar essa história evolutiva, contextualizando fisiológica e ecologicamente as alterações que ocorreram no perfil de utilização desses compostos. Para traçar essa história evolutiva, recorreu-se a dados disponíveis na literatura partindo-se dos elementos moleculares/metabólicos que compõem o ciclo do nitrogênio e em qual contexto geológico e evolutivo se deu tal história. Os dados obtidos, reorganizados e reestruturados nesse novo contexto, permitiram conclusões originais no presente trabalho, a saber: (1) a capacidade de fixação de nitrogênio atmosférico foi um fator de seleção natural positiva na transição da atmosfera redutora para oxidante; (2) os organismos fixadores de nitrogênio são bem mais disseminados do que o admitido classicamente; (3) o produto final da fixação biológica de nitrogênio in vivo são α- aminoácidos, e foram um fator de pressão seletiva para os organismos incapazes de fixar nitrogênio; (4) os metazoários evoluíram posteriormente a esse cenário e seu aparato metabólico está mais adaptado para o aproveitamento líquido do nitrogênio obtido apenas na forma de α-aminoácidos. / Metabolic pathway evolution models are molecular and computational based, and do not take account the physiological and ecological contexts in which organisms are inserted. Thus using the nitrogen metabolism as a platform, an evolutionary hypothesis on the α-amino acids utilization by metazoans was proposed. The objective of the present work is to trace an evolutionary history of the nitrogen usage by metazoans taking account the profile changes on a physiological and ecological basis. In order to trace this evolutionary history, a scrutiny were performed in the specialized literature aiming at data about the molecular and metabolic elements which perform the nitrogen cycle and in which geologic and evolutive context has passed such history. The reorganization of obtained data in a new context allowed original conclusions in the present work as follows: (1) the capability of fixing the atmospheric nitrogen was a positive selection factor in the atmospheric condition transition from reductive to oxidant; (2) nitrogen fixing organisms are far most wide spread than classically admitted; (3) α-amino acids are the biological nitrogen fixation end product in vivo, and are a selective factor for non-fixing organisms; (4) metazoans evolved afterwards in these scenario and their metabolic apparatus is adapted to the nitrogen net utilization obtained in the α-amino acid form.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-21T19:29:33Z No. of bitstreams: 1 2016 - Caroline Barra Sales Khayat da Costa.pdf: 5220401 bytes, checksum: 553248261c960b6b5fb62cadb1b26ebf (MD5) / Made available in DSpace on 2018-09-21T19:29:33Z (GMT). No. of bitstreams: 1 2016 - Caroline Barra Sales Khayat da Costa.pdf: 5220401 bytes, checksum: 553248261c960b6b5fb62cadb1b26ebf (MD5) Previous issue date: 2016-07-26 / CAPES / One of the most known and important process in nature is the biological nitrogen fixation (FBN). Few classes of microorganisms perform this process; named diazotrophics that associated with plants is an important alternative to enhance nitrogen nutrition in agricultural systems. Diazotrophic bacterial population in association with sugarcane improves the yield due to its ability to colonize the inner roots of the host plant and do not provoke any pathogenicity signal. Quantitative analyzes have indicated that selection of combinations of endophytic diazotrophic strains when associated with sugarcane varieties can improve the yield and therefore varieties of sugarcane may be better exploited in order to benefit this association for agricultural purposes. Thus, this work proposes to monitor the establishment of diazotrophic bacteria present in the inoculant of Embrapa, during the initial development of sugarcane plants. Micro-propagated sets of the sugarcane variety RB867515 were inoculated individually and with a mixture of five nitrogen fixing bacteria strains that compose the sugarcane inoculant: Nitrospirillum amazonense (CBAmC) Paraburkholderia tropica (Ppe8) Gluconacetobacter diazotrophicus (Pal5) Herbaspirillum seropedicae (HRC54) and Herbaspirillum rubrisubalbicans (HCC103). Plants were grown in a greenhouse and harvested 30 days after planting. Fresh root material was separated for evaluation of the establishment of the strains by bacterial counting using the technique of Most Probable Number (MPN), absolute quantification by Real Time PCR (qPCR), besides the identification of the inoculated strains through analysis of the rDNA profile of the pellicle formed in the respective semisolid media using the BOX-PCR technique. The results of bacterial count diazotrophic present in the roots by NMP showed that the treatments inoculated in the control (native population) showed higher population of bacterial cells around 105 cells by fresh root mass, but not statistically significant. The methodology qPCR permitted quantitation of the number of 16S rDNA copies in the order of 105 bacterial cells g - 1 fresh weight root, showing that there were differences in the population of endophytic species that colonize the roots of sugarcane. The profiles of BOX -PCR of the respective pellicles formed in semisolid media did not show high similarity (> 80 %) with the profile of the species inoculated for most of the treatments. The results obtained indicate that the qPCR technique showed the establishment of some of the inoculated strains in sugar cane buds while the NMP technique showed no significant difference between treatments inoculated and non-inoculated possibly due to the lower sensitivity of the method. / Um dos processos mais conhecidos e importantes na natureza ? a fixa??o biol?gica de nitrog?nio atmosf?rico (FBN). Este processo ? realizado por algumas classes de microrganismos, denominados diazotr?ficos, que associados com esp?cies vegetais s?o uma alternativa importante para aprimorar a nutri??o nitrogenada nos sistemas agr?colas. As popula??es de bact?rias fixadoras de nitrog?nio atmosf?rico quando associadas ? cultura da cana-de-a??car melhoram a produ??o e, ao colonizarem o interior das ra?zes promovem benef?cios ?s plantas hospedeiras. An?lises quantitativas t?m indicado que a sele??o das combina??es de estirpes de bact?rias diazotr?ficas endof?ticas e variedades de cana-de-a??car podem ser melhor exploradas com o objetivo de aperfei?oar a associa??o para finalidades agr?colas. Assim, o presente trabalho prop?e monitorar o estabelecimento das bact?rias diazotr?ficas presentes no inoculante para cana-de- a??car da Embrapa, durante o desenvolvimento inicial planta. Toletes propagados da variedade RB867515 de cana-de-a??car foram inoculados individualmente e com a mistura das cinco estirpes de bact?rias diazotr?ficas: Nitrospirillum amazonense (CBAmC), Paraburkholderia tropica (PPe8), Gluconacetobacter diazotrophicus (Pal5), Herbaspirillum seropedicae (HRC54) e Herbaspirillum rubrisubalbicans (HCC103). As plantas foram crescidas em casa de vegeta??o e coletadas 30 dias ap?s o plantio, sendo separado o material vegetal para avalia??o do estabelecimento das estirpes pela t?cnica do N?mero Mais Prov?vel (NMP) e quantifica??o absoluta por PCR em Tempo Real (qPCR). Adicionalmente foi feita a identifica??o das estirpes inoculadas atrav?s da an?lise do perfil de rDNA das pel?culas bacterianas formadas nos respectivos meios semiss?lidos pela t?cnica de BOX-PCR. Os resultados obtidos da contagem de bact?rias diazotr?ficas presente nas ra?zes por NMP mostrou que os tratamentos inoculados em rela??o ao controle (popula??o nativa), apresentaram uma maior popula??o de c?lulas bacterianas em torno de 105 c?lulas por massa fresca de raiz, por?m n?o significativa. A metodologia de qPCR permitiu a quantifica??o do n?mero de c?pias do 16S rDNA, da ordem de 105 c?lulas bacterianas g-1 massa fresca de raiz, mostrando que houve diferen?a na popula??o das esp?cies diazotr?ficas endof?ticas que colonizam as ra?zes de cana-de-a??car. Os perfis obtidos por BOX-PCR das pel?culas formadas nos respectivos meios semiss?lidos n?o mostraram alta similaridade (>80%) com o perfil das esp?cies inoculadas para a maioria dos tratamentos inoculados. Os resultados obtidos indicam que a t?cnica de qPCR permitiu mostrar o estabelecimento de algumas estirpe do inoculante nos toletes de cana-de a??car enquanto que a t?cnica de NMP n?o mostrou diferen?a significativas entre os tratamentos inoculados e n?o inoculados possivelmente pela menor sensibilidade da metodologia.

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Made available in DSpace on 2014-12-17T15:03:34Z (GMT). No. of bitstreams: 1 DanilloLMF_DISSERT.pdf: 2643693 bytes, checksum: e8aa0f4d4535d4002a68928f7529ab75 (MD5) Previous issue date: 2014-03-07 / In the state of Rio Grande do Norte (RN), Brazil, there are about 80 sewage treatment systems being the predominant technology waste stabilization ponds. The Baldo s WWTP , due to its location and low availability of area, was designed as a hybrid conventional system (UASB reactor followed by activated sludge with biodiscs) at a tertiary level, being the most advanced WWTP in the State and also with the larger treatment capacity (1620 m3/h) .The paper presents the results of its performance based on samples collections from May to December 2012. Composite samples of the effluent of the grit chamber, UASB reactors, anoxic chambers, aeration tanks and treated effluent were collected weekly, every 4 hours for 24 hours. The results showed that the WWTP effluent presented adequate ranges of temperatures, pH and DO, however removal efficiencies of BOD and TSS were below the predicted by design. The UASB reactors also showed removals of BOD and TSS less than expected, due to the accumulation of sludge in the reactors, which eventually, was washed out in the effluent. The nitrification process was not satisfactory mainly due to problems in the oxygen distribution in the aeration tanks. The removal of ammonia and TKN were high, probably by the assimilation process / No Rio Grande do Norte (RN), Brasil existe cerca de 80 sistemas de tratamento de esgotos sendo a tecnologia das lagoas de estabiliza??o a predominantemente utilizada. A ETE do Baldo, devido a sua localiza??o e disponibilidade de ?rea foi concebida como um sistema convencional h?brido (UASB lodos ativados com biodiscos) em n?vel terci?rio, sendo a ETE mais avan?ada do Estado e com maior capacidade de tratamento (1620 m 3 /h). O trabalho apresenta os resultados do seu monitoramento, atrav?s de coletas realizadas semanalmente no per?odo de junho a dezembro de 2012, com base em amostras compostas coletadas a cada 4 horas, durante 24 horas, do efluente da caixa de areia, reatores UASB, c?maras an?xicas, tanques de aera??o e efluente tratado. Os resultados mostraram que a ETE apresentou efluentes com temperaturas, pH e OD adequados, entretanto efici?ncias abaixo do projetado para os par?metros DBO e SST. Os reatores UASB tamb?m apresentaram remo??es de DBO e SST abaixo do esperado, devido ao ac?mulo de lodo nos reatores, uma vez que, este era expelido no efluente. O processo de nitrifica??o n?o foi satisfat?rio, pelas baixas concentra??es de nitrato encontradas nos efluentes dos tanques de aera??o, provavelmente por problemas no sistema de aera??o. As remo??es de am?nia e NTK foram altas, provavelmente pelo processo de assimila??o

Embrapa - Empresa Brasileira de Pesquisa Agropecuária / O Brasil é o maior produtor mundial de feijão-comum (Phaseolus vulgaris L.) e o grão é produzido em todo território nacional. Em seu cultivo predominam sistemas de produção com baixo índice de adoção de tecnologia e uso de insumos, porém existe uma parcela de produtores tecnificados. Com o lançamento da cultivar de feijão-comum superprecoce BRS FC104 estudos de manejo específicos para ela fizeram-se necessários. O objetivo deste estudo foi de determinar a melhor densidade de plantas para a cultivar; a responsividade da cultivar frente a inoculação das sementes com as estirpes SEMIA 4077, SEMIA 4080 e SEMIA 4088 de Rhizobium tropici; e a melhor época e dose de nitrogênio que deve ser aplicada em cobertura para expressão máxima da produtividade de grãos, dos demais componentes de produtividade, da espessura dos grãos e do teor de proteínas dos grãos nos cultivos de 1ª e 3ª safras. O incremento do número de plantas por hectare aumentou a produtividade de grãos, seja com ou sem a inoculação. A inoculação das sementes com as estirpes SEMIA 4077, SEMIA 4080 e SEMIA 4088 de Rhizobium tropici não apresentou resultados satisfatórios para as variáveis estudadas. A aplicação de nitrogênio em cobertura é uma prática fundamental para se obter ganhos em produtividade de grãos na 3ª safra. A aplicação de nitrogênio na germinação das sementes reduziu a população final de plantas. / Brazil is the world’s largest producer of common bean (Phaseolus vulgaris L.) and grain is produced throughout the country. In its cultivation, systems of production with low index of technology use and inputs use predominate, but there is still a portion technified producers. With the launching of super early common bean cultivation BRS FC104 management studies specific for it are needed. The objective of this study is to determine the best density of plants for a cultivation; a responsiveness of the cultivation to seed inoculation with SEMIA 4077, SEMIA 4080 and SEMIA 4088 of Rhizobium tropici strains; and the best time and nitrogen dose that should be applied in coverage for maximum expression of grain yield, other productivity components, grain thickness and grain protein content in 1st and 3rd crop crops. The increase in number of plants per hectare increased grain yield, either with or no inoculation. Seed inoculation with the strains SEMIA 4077, SEMIA 4080 and SEMIA 4088 of Rhizobium tropici did not present satisfactory results for the studied variables. The application of nitrogen under cover is a fundamental practice to obtain gains in grain yield in the 3rd crop. The application of nitrogen in the germination of the seeds reduced the final population of plants. / Dissertação (Mestrado)

Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2019 / Simultaneous nitrification and aerobic denitrification (SNaD) is a preferred method for single stage total nitrogen (TN) removal, which was recently proposed to improve wastewater treatment plant design. However, SNaD processes are prone to inhibition by toxicant loading with free cyanide (CN-) possessing the highest inhibitory effect on such processes, rendering these processes ineffective. Despite the best efforts of regulators to limit toxicant disposal into municipal wastewater sewage systems (MWSSs), free cyanide (CN-) still enters MWSSs through various pathways; hence, it has been suggested that CN- resistant or tolerant microorganisms be utilized for processes such as SNaD. To mitigate toxicant loading, organisms in SNaD have been observed to adopt a multiphase growth strategy to sequentially degrade CN- during primary growth and subsequently degrade TN during the secondary growth phase. However, CN- degrading microorganisms are not widely used for SNaD in MWSSs due to the inadequate application of suitable microorganisms (Chromobacterium violaceum, Pseudomonas aeruginosa, Thiobacillus denitrificans, Rhodospirillum palustris, Klebsiella pneumoniae, and Alcaligenes faecalis) commonly used in single-stage SNaD. The use of CN- degrading or resistant microorganisms for SNaD is a cost-effective method compared to the use of other methods of CN- removal prior to TN removal, as they involve multi-stage systems (as currently observed in MWSSs). The use of CN- degrading microorganisms, particularly when used as a consortium, presents a promising and sustainable resolution to mitigate inhibitory effects of CN- in SNaD. However, SNaD is known to be completely inhibited by CN- thus it is imperative to also study some thermodynamic parameters of SNaD under high CN- conditions to see the feasibility of the process. The Gibbs free energy is significant to understand the feasibility of SNaD, it is also vital to study Gibbs free energy to determine whether or not the biological reaction is plausible. The relationship between the rate of nitrification and Gibbs free energy was also investigated. The attained results showed that up to 37.55 mg CN-/L did not have an effect on SNaD. The consortia degraded CN- and achieved SNaD, with degradation efficiency of 92.9 and 97.7% while the degradation rate of 0.0234 and 0.139 mg/L/hr for ammonium-nitrogen (NH4-N) and CN- respectively. Moreover, all the free Gibbs energy was describing the individual processes were found to be negative, with the lowest Gibbs free energy being -756.4 and -1830.9 Kcal/mol for nitritation and nitratation in the first 48 h of the biological, reaction respectively. Additionally, a linear relationship between the rate of NH4-N and nitrite-nitrogen (NO2-N) degradation with their respective Gibbs free energy was observed. Linear model was also used to predict the relationship between NH4-N, NO2-N degradation and Gibbs free energy. These results obtained showed a good correlation between the models and the experimental data with correlation efficiency being 0.94 and 0.93 for nitritation, and nitratation, respectively. From the results found it can be deduced that SNaD is plausible under high cyanide conditions when cyanide degrading or tolerant microorganisms are employed. This can be a sustainable solution to SNaD inhibition by CN- compounds during wastewater treatment. Furthermore, a single strain was purified from the consortium and identified as Acinetobacter courvalinii. This bacterial strain was found to be able to perform sequential CN- degradation, and SNaD; an ability associated with multiphase growth strategy of the microorganism when provided with multiple nitrogenous sources, i.e. CN- and TN. The effect of CN- on nitrification and aerobic denitrification including enzyme expression, activity and protein functionality of Acinetobacter courvalinii was investigated. It was found that CN- concentration of up to 5.8 mg CN-/L did not affect the growth of Acinetobacter courvalinii. In cultures whereby the A. courvalinii isolate was used, degradation rates of CN- and NH4-N were found to be 2.2 mg CN-/L/h and 0.40 mg NH4-N/L/h, respectively. Moreover, the effect of CN- on NH4-N, nitrate-nitrogen (NO3-N) and NO2-N oxidizing enzymes was investigated, with findings indicating CN- did not affect the expression and activity of ammonia monooxygenase (AMO), but affected the activity of nitrate reductase (NaR) and nitrite reductase (NiR). Nevertheless, a slow decrease in NO2-N was observed after the addition of CN- thus confirming the activity of NaR and the activation of the denitrification pathway by the CN-. Moreover, five models’ (Monod, Moser, Rate law, Haldane, and Andrew’s model) ability to predict SNaD under CN- conditions, indicated that only Rate law, Haldane and Andrew’s models, were suited to predict both SNaD and CN- degradation. Due to low degradation rates of NH4-N and CN-, optimization of SNaD was essential. Therefore, response surface methodology was used to optimize the SNaD under CN- conditions. The physiological parameters that were considered for optimization were temperature and pH; with the result showing that the optimum for pH and temperature was 6.5 and 36.5oC respectively, with NH4-N and CN- degradation efficiency of 50 and 80.2%, respectively. Furthermore, the degradation kinetics of NH4-N and CN- were also studied under the optimum conditions in batch culture reactors, and the results showed that up to 70.6% and 97.3% of NH4-N and CN- were simultaneously degraded with degradation rates of 0.66 and 0.41 mg/L/h, respectively. The predictive ability of RSM was further compared with cybernetic models, and cybernetic models were found to better predict SNaD under CN- conditions. These results exhibited a promising solution in the management of inhibition effected of CN- towards SNaD at an industrial scale.

En aquesta tesi es presenten dues propostes de Sistemes de Control basats en Lògica Difusa (SCLD), des del seu disseny fins a la seva implementació i validació en dues instal·lacions: l'EDAR Granollers i l'EDAR Taradell.El capítol 1 explica els conceptes bàsics per comprendre el desenvolupament dels dos SCLD i el resum d'una revisió d'articles que relacionen la lògica difusa amb aigües residuals. A continuació, s'estableixen els objectius. En el capítol 3 es presenten els materials i mètodes. Els capítols 4 i 5 exposen el treball realitzat per arribar a la implementació dels dos SCLD. Ambdós capítols presenten la mateixa estructura: presentació, definició dels objectius del SCLD, descripció de l'EDAR on s'implementa el SCLD, desenvolupament d'índexs d'avaluació, explicació del disseny del SCLD i la seva avaluació mitjançant estudis de simulació, implementació i validació del SCLD a l'EDAR i, finalment discussió del treball realitzat. En el capítol 6 s'enumeren les conclusions obtingudes. / This thesis presents two proposals of Fuzzy Logic Control Systems (FLCS's), from their design to their implementation and validation in two facilities: Granollers and Taradell WWTP. The fundamental concepts to understand the FLCS's development are explained in the first chapter with a summary of scientific papers related to fuzzy logic applications in the wastewater treatment. The objectives are established in Chapter 2 and the materials and methods are described in Chapter 3.In Chapters 4 and 5, the work to design, implement and validate the FLCS's is presented. Both chapters have the same structure: a presentation, a goal definition of FLCS, a description of the WWTP, the evaluation index development, a detailed explanation about designing the FLCS process and its evaluation by simulation studies, the implementation of FLCS to WWTPs and their validation and, finally, a discussion of the work carried out is presented. The main conclusions are enumerated in Chapter 6.

Made available in DSpace on 2014-07-29T15:16:33Z (GMT). No. of bitstreams: 1 Dissertacao_Daiana_Fernandes.pdf: 425302 bytes, checksum: 7de511c42aac920ca200b0a0f5e3892e (MD5) Previous issue date: 2009-04-30 / The soybeans and beans are of great economic and social importance to Brazil. From the nutritional point of view, they are very demanding in nitrogen and to supply its demand both species are able Biological Nitrogen Fixation (BNF). However, for the BNF, rhizobia require energy supply by the carbohydrates from photosynthesis. For this reason the availability of fotossintato is the biggest limiting factor in BNF. This work had as propose to evaluate the influence of inoculation with rhizobia in two phenological stages of plants under different levels of shading. In this context the inoculation was assessed by the following treatments: two species of legume (Phaseolus vulgaris, L. and Glycine max, L.) inoculated and not inoculated (Fi, Fni, Si and Sni) with specific strains (Rhizobium tropici and Bradyrhizobium japonicum and B. elkanii) in two phenological stages (before, Ep1, and after flowering, Ep2) and subjected to three shadow levels (no shade, 70% and 80% of shade). The experimental design was completely randomized in four replicates on the experiments 1, 2, 3 and 4 conducted in a greenhouse and three replicates for the experiments 5, 6, 7 and 8 in the external environment to a greenhouse. In experiments 1 and 3, both species have continued forming nodules after flowering, the plants of these treatments Fni Ep2, Sni Ep2 and Si Ep2 had the highest average for the number, volume, fresh weight and dry weight of nodules. As the activity of the nodules, the plants of treatments Fi Ep1 and Si Ep1 had the highest number of active nodules compared to treatments Fni Ep2 and Sni Ep2. Assessing the effect of shading in experiments 2 and 4, it was found that bean and soybean plants have behaved differently. The shading of 80% favored the formation of nodules in inoculated bean deferring between treatments of shading, in contrast to the soybean plants that there was no difference (p ≥ 0.05) among treatments. There was no statistical difference between treatments in the number of active nodes for the beans; the plants of the Sni treatment 80% had the lowest number of active nodules compared to the plants of treatment Si 0%. In experiments 5 and 7 plants of soybeans and reduced the number of nodules after flowering, and as in Experiment 1 and 3 there was a higher number of active nodes during the growing season compared to the reproductive period. The shading applied in bean plants (Experiment 6) was not enough to cause no difference between treatments on the number and activity of nodules; in the experiment with 8 soybean, the shading changed patterns of nodulation and activity of nodules (p ≥ 0.05). It is this work that the formation and maintenance of activity of the nodules were so distinct in vegetative and reproductive stages, but the shading of 70 and 80% applied was not sufficient to cause significant change in activity of the nodules, suggesting that the reduction the availability of fotossintatos is not the limiting factor in determining the efficiency of N, mainly in the bean / A soja e o feijão são leguminosas de grande importância econômica e social para o Brasil. Do ponto de vista nutricional, são muito exigentes em nitrogênio e para suprir esta demanda ambas às espécies são hábeis em fixá-lo simbioticamente. Mas, para fixar simbioticamente o nitrogênio, os rizóbios necessitam de energia de carboidratos proveniente da fotossíntese. Por esta razão a disponibilidade de fotossintato é o maior fator limitante na Fixação Biológica de Nitrogênio (FBN). Este trabalho se propôs a avaliar a influência da inoculação com rizóbios em dois estádios fenológicos de plantas submetidas a diferentes níveis de sombreamento. Neste contexto foi avaliada a inoculação mediante os seguintes tratamentos: duas espécies de leguminosas (Phaseolus vulgaris, L. e Glycine max, L.) estando elas inoculadas e não inoculadas (Fi, Fni, Si e Sni) com estirpes específicas (Rhizobium tropici e Bradyrhizobium japonicum e B. elkanii) em dois estádios fenológicos (antes, Ep1, e após a floração, Ep2) e submetidas à três níveis de sombreamento (sem sombreamento, 70% e 80% de sombra). O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições para os experimentos 1, 2, 3 e 4 conduzidos em casa de vegetação e três repetições para os experimentos 5, 6, 7 e 8 conduzidos em ambiente externo a casa de vegetação. Nos experimentos 1 e 3, ambas as espécies continuaram formando nódulos após a floração, nestes as plantas dos tratamentos Fni Ep2, Sni Ep2 e Si Ep2 apresentaram as maiores médias para o número, volume, massa fresca e massa seca de nódulos. Quanto à atividade dos nódulos, as plantas dos tratamentos Fi Ep1 e Si Ep1 apresentaram o maior número de nódulos ativos comparados aos tratamentos Fni Ep2 e Sni Ep2. Avaliando o efeito do sombreamento nos experimentos 2 e 4, observou-se que as plantas de feijão e soja se comportaram de forma diferente. O sombreamento de 80% favoreceu a formação de nódulos no feijoeiro inoculado deferindo entre os tratamentos de sombreamento, ao contrário das plantas de soja que não houve diferença (p ≥ 0,05) entre os tratamentos. Não houve diferença estatística entre os tratamentos quanto ao número de nódulos ativos para o feijão; as plantas do tratamento Sni 80% obtiveram o menor número de nódulos ativos comparado às plantas do tratamento Si 0%. Nos experimentos 5 e 7 as plantas de feijão e soja reduziram o número de nódulos após a floração, e assim como no experimento 1 e 3, observou-se maior número de nódulos ativos durante o período vegetativo comparado ao período reprodutivo. O sombreamento aplicado nas plantas de feijão (Experimento 6) não foi suficiente para causar nenhuma diferença entre os tratamentos quanto ao número e atividade dos nódulos; no experimento 8 com soja, o sombreamento alterou os padrões de nodulação e atividade dos nódulos (p ≥ 0,05). Conclui-se neste trabalho, que a formação e manutenção da atividade dos nódulos ocorreram de maneira distinta nos estádios vegetativos e reprodutivos, contudo o sombreamento de 70 e 80% aplicado não foi suficiente para causar alteração notável na atividade dos nódulos, sugerindo que a redução na disponibilidade de fotossintatos não é o fator limitante na eficiência de fixação do N, principalmente no feijoeiro

Orientador: Marcelo Carvalho Minhoto Teixeira Filho / Resumo: Alternative management practices are needed to minimize the need for chemical fertilizer use in non-leguminous cropping systems. The use of biological agents which can fix atmospheric nitrogen and promote plant growth has shown potential as an option to improve soil nutrient availability to grass crops. In recent years, studies investigating the effects of silicon (Si) have increased substantially, especially in grain crops. This increased interest in Si is likely due to the beneficial effects of Si application on plant resistance to abiotic and biotic stresses, reflecting on greater plant development. This research was developed to investigate if inoculation of corn and wheat with Azospirillum brasilense associated with Si can enhance nitrogen use efficiency (NUE) and improve plant nutrition and yield, leading to a greater economic profit. The study was set up in a Rhodic Haplustox under no-till system, located in Selvíria, state of Mato Grosso do Sul, Brazil. The field trial took place during the 2015/16 (November-March), 2016 (April-September), 2016/17 (November-March) and 2017 April-September) seasons, with corn and wheat crops in sucession (spring/summer and winter seasons for corn and wheat, respectively). Treatments were tested in a randomized completely block design with four replicates, arranged in a full factorial design 5 × 2 × 2 and included: i) five N application rates, as urea source, applied in side-dressing (0, 50, 100, 150 and 200 kg ha-1); ii) two liming sou... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor