Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2016-10-04T21:35:58Z No. of bitstreams: 1 2010 - Andr? Fern?o Martins de Andrade.pdf: 4307696 bytes, checksum: d679370ce9902b97ed91c98436c9103a (MD5) / Made available in DSpace on 2016-10-04T21:35:58Z (GMT). No. of bitstreams: 1 2010 - Andr? Fern?o Martins de Andrade.pdf: 4307696 bytes, checksum: d679370ce9902b97ed91c98436c9103a (MD5) Previous issue date: 2010-08-31 / UNIFOA / This study begun with a field survey in a one hectare area of petroleum drill waste (rocks and mud came from perforation) in Santa Maria do Oeste, in Paran? state, Brazil. It was verified different levels of metal contamination in the area, according to the surface position and with depth, with barium and lead over the investigation standard according to legislation. The highest level contaminated material was collected and used in a laboratory and greenhouse experiment at the campus of the Universidade Federal Rural do Rio de Janeiro, initiated on December, 2007, and completed on June, 2010. The objective was to evaluate the efficiency of remediation by washing contaminated soil (in situ and ex-situ) as well as phytoremediation. The waste washing ex-situ was simulated such as the contaminant would be removed from soil using a rotating device, with soil mixed with an ethylenediaminetetraacetic acid (EDTA) solution in the proportion of 1:10. Removal of lead and calcium increased proportionally to concentration of extractor (from 100 to 1500 mmol L-1). Removal of barium increased considerably above 600 mmol L-1. Iron and manganese showed little influence by different concentration of extractor. The soil washing in-situ was simulated by addition of two solutions of EDTA, with concentration of 150 and 300 mmol L-1, and the control (water). The material was incubated in plastic columns, for three weeks, after that volumes of 100 mL of deionized water were added weekly for three weeks, and after that samples were taken daily up to a total of ten. The leached was collected and the barium and lead content were analyzed, also other metals that could interfere with the extraction. The fractions (exchangeable, iron bound, organic matter bound, and residual) that metals were associates in the waste, before and after washing, were also determined. It was found, in the higher EDTA concentration, a small extraction of barium, while lead had about 20% of the total in soil extracted. The phytoremediation was carry on with two species, Brachiaria decumbens cv. Basilisk, an herbaceous plant, and Cordia africana, an arboreal. The plants growing up in vases with 4 kg of substratum were irrigated with deionized water and Hoagland nutrient solution (25% of ionic power). Two treatments were used in the phytoextraction induced with EDTA, in the concentration of 6 mmol L-1 (with one single application, and 3 dosages of 2 mmol L-1), plus the control. After 150 days for Brachiaria and 270 days for Cordia, the plants were collected, and analyzed (root and shoots) for heavy metal content. EDTA was effective to induce metal absorption, except for barium and calcium, where lead concentrated in the roots and barium in leaves (with highest concentration for EDTA applied in one dose). For Cordia, barium distributed equally in the plant sections, and lead concentrated in the roots. / Este trabalho iniciou-se com levantamento de campo na ?rea de despejo do res?duo de perfura??o de po?o de prospec??o de petr?leo (cascalhos e fluidos da broca) em Santa Maria do Oeste, Estado do Paran?, que possui ?rea aproximada de um hectare. Constatou-se que a ?rea apresentava diferentes n?veis de contamina??o de metais, estando, de acordo com sua posi??o no plano e em profundidade, com n?veis de b?rio e o chumbo na faixa de investiga??o, conforme norma legal. O material com maior n?vel de contamina??o foi coletado e utilizado em experimento de laborat?rio e casa de vegeta??o no campus da Universidade Federal Rural do Rio de Janeiro, a partir do m?s de dezembro de 2007 e finalizado em junho de 2010. Objetivou-se avaliar a efici?ncia da remedia??o atrav?s da lavagem do solo contaminado (in situ e ex-situ) bem como da sua fitorremedia??o. A lavagem do res?duo ex-situ foi simulada como aquela em que o contaminante seria removido do solo em um reator rotativo, onde o solo seria misturado em batelada a solu??o de EDTA na propor??o 1:10. A remo??o de chumbo e c?lcio aumentou com o aumento da concentra??o do extrator (de 100 a 1500 mmol L-1). A remo??o do b?rio aumentou consideravelmente acima de 600 mmol L-1; ferro e mangan?s foram pouco influenciados pelas diferentes concentra??es. A lavagem do solo in situ foi feita com adi??o de duas solu??es de ?cido etilenodiamino tetra-ac?tico diss?dico (Na2EDTA), de concentra??es 150 e 300 mol L-1, al?m da testemunha (?gua), em colunas est?ticas que, ap?s um per?odo de tr?s semanas de incuba??o, receberam 100 mL de ?gua deionizada a cada semana por tr?s semanas e, depois, uma coleta por dia at? perfazer 10 coletas. Os lixiviados foram coletados e analisados os teores dos contaminantes b?rio e chumbo, al?m de outros metais interferentes com a extra??o. Determinou-se, ainda, as diversas fra??es (troc?vel, ligada a ?xidos, ligada ? mat?ria org?nica e residual) em que esses metais se encontravam no res?duo antes e ap?s a lavagem. Foi verificada, na maior concentra??o de EDTA, extra??o insignificante de b?rio, enquanto o chumbo teve extra?do cerca de 20% do seu total no solo. A fitorremedia??o deu-se por meio do uso de duas esp?cies, uma herb?cea (Brachiaria decumbens cv. Basilisk) e outra lenhosa (Cordia africana). As plantas se desenvolveram em vasos com 4 kg de substrato, recebendo fertirriga??o (solu??o de Hoagland a 25% de for?a i?nica). Foram usados dois tratamentos na fitoextra??o induzida com EDTA, na concentra??o de 6 mmol L-1 em duas formas de aplica??o (3 aplica??es de 2 mmol.L-1 e uma de 6 mmol L-1) e a testemunha. Ap?s per?odo de desenvolvimento de 150 dias para a braqui?ria e de 270 dias para a c?rdia, as plantas foram coletadas tendo suas ra?zes e a parte a?rea analisada quanto ao conte?do de metais. Na braqui?ria, o EDTA foi efetivo na indu??o da absor??o dos metais com exce??o do b?rio e do c?lcio, tendo o chumbo se concentrado nas ra?zes e o b?rio nas folhas (com maior concentra??o no tratamento de aplica??o ?nica de EDTA). Na c?rdia, o b?rio distribuiu-se igualmente entre as partes analisadas e o chumbo se concentrou nas ra?zes.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2016-10-25T19:13:03Z No. of bitstreams: 1 2000 - Eva Aparecida de Souza.pdf: 524982 bytes, checksum: e193e5f67e0c9dafb75bc879a9949011 (MD5) / Made available in DSpace on 2016-10-25T19:13:03Z (GMT). No. of bitstreams: 1 2000 - Eva Aparecida de Souza.pdf: 524982 bytes, checksum: e193e5f67e0c9dafb75bc879a9949011 (MD5) Previous issue date: 2000-09-29 / Cassava (Manihot esculenta Crantz) is one of the main sources of carbohydrates for human food in the tropics, part of the staple food of about 500 million people, mainly in developing countries. The literature on cassava nitrogenous fertilization is scarce. This study aimed to evaluate the effects of levels and nitrogenous fertilizer sources on dry matter and nitrogen accumulation in roots and aerial parts of cassava. The experiment was conducted at the Experimental Station of Itagua?/PESAGRO-Rio in Serop?dica, State of Rio de Janeiro, on a Red-Yellow Podzolic soil, in the period May 1999 to June 2000. The design of the field experiment was in randomized blocks with four repetitions, in a 3 x 5 factorial outline, made up of by three N sources (urea, nitrocalcium and ammonium sulphate) and five N levels (0, 60, 120, 180 and 200 kg N ha-1). Each plot had 64.0 m2 with 12 grooves, spaced at 1.0m. The planting was carried out on 28/05/1999 with cuttings of cultivar Saracura. The nitrogen levels were divided into two applications, the first half was applied planting and other half was applied 9 month later. Plants were harvested at 07, 11 and 13 months after planting and determined dry matter, total nitrogen, nitrate-N, amino-N, crude protein and soluble sugars in roots, leaves and stem. To 7 months after planting, urea showed higher total dry matter value. At 13 months, nitrocalcium and ammonium sulphate provided dry matter root yield 20 % higher than the urea. The N content in leaves was approximately 7 times bigger those the N root contents. The application of 30 kg N ha-1 resulted in increase of 11% in leaf N content. There was a cassava response to N application and can behave as a specie efficient responsive little. / A mandioca ? uma das principais fontes de carboidratos nos tr?picos, fazendo parte da alimenta??o b?sica de cerca de 500 milh?es pessoas, principalmente em pa?ses em desenvolvimento. Estudos com aduba??o nitrogenada em mandioca s?o escassos. O presente trabalho objetivou-se avaliar o efeito de fontes e n?veis de adubos nitrogenados sobre o ac?mulo de mat?ria seca e distribui??o de nitrog?nio nas ra?zes e parte a?rea da cultura da mandioca. O experimento foi instalado na Esta??o Experimental de Itagua? (PESAGRO-RJ), sobre um solo Podz?lico Vermelho-Amarelo distr?fico, no periodo de maio de 1999 a junho de 2000. Utilizou-se o delineamento de blocos ao acaso no esquema fatorial 3 x 5 com quatro repeti??es. Foram avaliadas tr?s fontes de nitrog?nio: ur?ia, nitroc?lcio e sulfato de am?nio, combinadas em cinco n?veis de aplica??o de N: 0; 60; 120; 160 e 200 kg N ha-1. Cada parcela apresentou 64 m2 com 12 sulcos, espa?ados de 1,0 m. O plantio foi realizado em 28/05/1999, usando-se manivas da cultivar Saracura, obtidas de fonte comercial da regi?o produtora de Santa Cruz, munic?pio do Rio de Janeiro. As doses de N foram aplicadas parceladamente, sendo metade por ocasi?o do plantio e a outra metade aos nove meses ap?s o plantio. Foram realizadas coletas de material vegetal aos sete, onze e aos treze meses ap?s plantio para determinar as seguintes vari?veis: massa seca, N-total, prote?na bruta, N-amino, N-nitrato e a??cares sol?veis de ra?zes, folhas e caule. Aos sete meses ap?s o plantio, a ureia apresentou maior valor de massa seca total. Aos 13 meses, nitroc?lcio e sulfato de am?nio proporcionaram rendimento de massa seca de raiz 20% superior ao da ur?ia. A aplica??o de 30 kg N ha-1 resultou em um aumento de 11% no teor de N em folhas. O teor de N em folhas foi aproximadamente sete vezes maior ao N da raiz. Durante o per?odo de crescimento da cultura, houve uma resposta da mesma ? aplica??o de N, podendo se comportar como uma esp?cie eficiente pouco responsiva.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-08T16:51:22Z No. of bitstreams: 1 2016 - Rennan do Amaral Bastos.pdf: 2824478 bytes, checksum: 5a974a7444eaef272210a147add547a0 (MD5) / Made available in DSpace on 2017-02-08T16:51:22Z (GMT). No. of bitstreams: 1 2016 - Rennan do Amaral Bastos.pdf: 2824478 bytes, checksum: 5a974a7444eaef272210a147add547a0 (MD5) Previous issue date: 2016-02-04 / The objective of this work was to evaluate the production of biomass and grains in common bean (Phaseolus vulgaris) in co-inoculation with rhizobia and plant growth promoting bacteria. The work was divided into three chapters. The first evaluated the compatibility between rhizobia and plant growth promoting bacteria and their effects on plant growth. In Petri dishes assay, Azospirillum amazonense and A. brasilense were co-inoculated with Rhizobium tropici at three application levels, and no antagonism was detected. The experiment in Leonard jars had a 5x3+3 factorial with eight replications, consisting of five bacteria (Bradyrhizobium diazoefficiens, B. elkanii, A. amazonense, Azospirillum brasilense and Escherichia coli) and three application levels (104, 106 and 108 CFU mL-1), all co-inoculated with R. tropici plus three additional treatments (control, nitrogen, and inoculated with R. tropici). Co-inoculation increased nodulation, N concentration and content in the shoot. The experiment in pots with soil had 3x2x2+4 factorial with four replications, consisting of three growth promoters (B. diazoefficiens, B. elkanii and A. brasilense), two application levels (104 and 106 CFU mL-1), two N sources (R. tropici and mineral N), and four additional control treatments (absolute control, nitrogen, inoculated with rhizobia and co-inoculated with AZOTOTAL?). Inoculation with A. brasilense associated with N fertilization increased the production of leaves and shoots. The second chapter aimed to evaluate the growth and production of common bean under co-inoculation. An experiment in pots with soil in a factorial 2x3+4 with 8 repetitions were performed by combining the inoculation of R. tropici with A. brasilense or B. diazoefficiens in three application levels (104, 106 and 108 CFU mL-1) plus the control treatments (absolute, nitrogen, inoculated with rhizobia and co-inoculated with AZOTOTAL?). Four replications were harvested at 45 days after sowing, and four at grain maturity. Co-inoculated plants showed shoot mass, number of pods, shoot N content, grain yield, number of seeds and pods per plant higher than the control inoculated with rhizobia. The leaf chlorophyll Falker index was similar in co-inoculated treatments and under mineral N fertilization, but lower than the exclusive inoculation R. tropici. In the third chapter it was evaluated the growth and production of common bean under different strategies of mineral N fertilization associated with co-inoculation with R. tropici and A. brasilense. The experiment had seven treatments with four replications: control; inoculation with R. tropici without N application; control with mineral N; co-inoculation with R. tropici and A. brasilense without N fertilization or application of 20 kg ha-1 of N at sowing; inoculation with R. tropici and 20 kg ha-1 of N at sowing; inoculation with A. brasilense and 20 kg ha-1 of N at sowing. Plants were harvested at 45 days after sowing and at grain maturity. Co-inoculation combined with the N fertilization resulted in higher mass values of leaves, stem, shoot, dry mass of grains, number of grains per plant and accumulation of N in pods and grains. / O objetivo do trabalho foi avaliar a produ??o de biomassa e de gr?os em feijoeiro comum (Phaseolus vulgaris) sob co-inocula??o de riz?bio e bact?rias promotoras de crescimento vegetal. O trabalho foi dividido em tr?s cap?tulos. O primeiro teve como objetivo avaliar a compatibilidade entre riz?bio e bact?rias promotoras de crescimento e seus efeitos no crescimento das plantas. Em ensaio em placas de Petri, Azospirillum amazonense e A. brasilense foram co-inoculados com Rhizobium tropici em tr?s doses de aplica??o, verificando-se aus?ncia de antagonismo. O experimento em vasos de Leonard teve esquema fatorial 5x3+3 com oito repeti??es, composto por cinco bact?rias (Bradyrhizobium diazoefficiens, B. elkanii, Azospirillum amazonense, A. brasilense e Escherichia coli) e tr?s doses de aplica??o (104, 106 e 108 UFC mL-1), todas co-inoculadas com R. tropici, e tr?s tratamentos adicionais (testemunhas absoluta, nitrogenada, e inoculada com R. tropici). A co-inocula??o aumentou a nodula??o, teor e conte?do de N na parte a?rea. O experimento em vasos com solo teve esquema fatorial 3x2x2+4 com quatro repeti??es, composto por tr?s promotores de crescimento (B. diazoefficiens, B. elkanii e A. brasilense), duas doses (104 e 106 UFC mL-1), duas fontes de N (R. tropici e N mineral), e quatro tratamentos adicionais (testemunhas absoluta, nitrogenada, inoculada com riz?bio e co-inoculada com AZOTOTAL?). A inocula??o com A. brasilense associada ? aduba??o nitrogenada aumentou a produ??o de folhas e de parte a?rea. O segundo cap?tulo teve como objetivo avaliar o crescimento e produ??o do feijoeiro sob co-inocula??o. Foi realizado um experimento em vasos com solo em esquema fatorial 2x3+4 com oito repeti??es, combinando a inocula??o de R. tropici com A. brasilense ou B. diazoefficiens e tr?s doses de aplica??o (104, 106 e 108 UFC mL-1), acrescidos das testemunhas absoluta, nitrogenada, inoculada com riz?bio e co-inoculada com AZOTOTAL?. As plantas foram coletadas aos 45 dias ap?s plantio e na matura??o dos gr?os. As plantas co-inoculadas apresentaram massa de parte a?rea, n?mero de vagens, conte?do de N na parte a?rea, massa de gr?os, n?mero de gr?os e de vagens por planta, superiores ? testemunha inoculada com riz?bio. O ?ndice de clorofila Falker foi similar nos tratamentos co-inoculados e sob aduba??o nitrogenada, mas inferior ao da inocula??o com R. tropici. No terceiro cap?tulo avaliou-se o crescimento e produ??o do feijoeiro sob diferentes estrat?gias de aduba??o nitrogenada associada ? co-inocula??o. O experimento consisitu de sete tratamentos com oito repeti??es: testemunha absoluta; inocula??o com R. tropici sem aplica??o de N; testemunha com N mineral; co-inocula??o com R. tropici e A. brasilense sem N ou com 20 kg ha-1 de N em semeadura; inocula??o com R. tropici e 20 kg ha-1 de N em semeadura; inocula??o com A. brasilense e 20 kg ha-1 de N em semeadura. As plantas foram coletadas aos 45 dias e na matura??o. A co-inocula??o combinada com a aduba??o nitrogenada resultou em maiores valores de massa de folhas, caule, parte a?rea, massa seca de gr?os, n?mero de gr?os por planta e ac?mulo de N nas vagens e gr?os.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-09T19:35:26Z No. of bitstreams: 1 2016 - Camila Gomes Nunes.pdf: 4871207 bytes, checksum: 62e59136c5dda645d85ce86beadae3ca (MD5) / Made available in DSpace on 2017-02-09T19:35:26Z (GMT). No. of bitstreams: 1 2016 - Camila Gomes Nunes.pdf: 4871207 bytes, checksum: 62e59136c5dda645d85ce86beadae3ca (MD5) Previous issue date: 2016-08-22 / Despite the nutritional and functional value the fruits of jamel?ozeiros (Syzygium Cumini L. Skeels) known as jamel?es are little consumed. In harvest seasons, production is abundant, however, there is no rational use of the fruit. The pulp of this fruit has a high content of anthocyanin, which gives it high antioxidant potential. The practice of physical exercise generates free radicals in the body, which has the antioxidant defense system; the effectiveness of this system is modulated by the intake of nutrients and other compounds with antioxidant potential, as presents in Jamel?o. The aim of the paper was develop energy drink, formulation for use with Jamel?o pulp and mix of carbohydrates, 100% natural, without colorings and flavorings. 11 formulations were produced according to the RDC / ANVISA n?18/2010, with variations in pulp content and mix of carbohydrates. The samples were subjected to sensory evaluation by the acceptance method with consumers and 4 samples with higher averages passed new sensory analysis by athletes, acceptance method and were also submitted to: physical analysis, chemical and physico-chemical, antioxidant activity by methods DPPH, anthocyanin content and content of phenolic compounds. The formulations 4,5,8 and 11 obtained the highest average with consumers and the sample 11 to greater acceptance by athletes. The sample 8 had higher anthocyanin content differing from the other. The sample 4 and 5 showed higher levels of phenolic and the sample 4 presented the highest antioxidant activity. In conclusion, the beverage had high and satisfactory levels of antioxidants and good acceptance by athletes. Therefore, the production of energy and functional drink for athletes and favors the development of new products using Jamel?o must be encouraged and exploited. / Apesar do valor nutricional e funcional, os frutos dos jamel?ozeiros (Syzygium Cumini L. Skeels) conhecidos como jamel?es, s?o pouco consumidos. Nas ?pocas de safra, a produ??o ? abundante, no entanto, n?o h? uso racional do fruto. A polpa desse fruto apresenta alto teor de antocianinas, que lhe confere alto potencial antioxidante. A pr?tica de exerc?cios f?sicos gera radicais livres no organismo que conta com o sistema de defesa antioxidante, a efic?cia desse sistema ? modulada pela ingest?o de nutrientes e outros compostos com potencial antioxidante, como os presentes no jamel?o. Desenvolver formula??o de bebida energ?tica pronta para consumo com polpa de jamel?o e mistura de carboidratos, 100% natural, sem corantes e aromatizantes. Foram produzidas 11 diferentes formula??es conforme a RDC/ANVISA n?18/2010, com varia??es no teor de polpa e do mix de carboidratos. As amostras foram submetidas a an?lise sensorial pelo m?todo de aceita??o com consumidores e as 4 amostras com maiores m?dias passaram por nova an?lise sensorial pelo m?todo de aceita??o com atletas e foram submetidas tamb?m a: An?lise f?sica, qu?mica e f?sico-qu?mica, atividade antioxidante pelos m?todos DPPH, teor de antocianinas e teor de compostos fen?licos totais. As formula??es 4,5,8 e 11 obtiveram as maiores m?dias com os consumidores sendo a amostra 11 a de maior aceita??o pelos atletas. A amostra 8 apresentou maior teor de antocianina diferindo das demais. As amostra 4 e 5 apresentaram maiores teores de compostos fen?licos sendo a amostra 4 a que apresentou maior atividade antioxidante. Em conclus?o, a bebida desenvolvida apresentou teores elevados e satisfat?rios de compostos antioxidantes e boa aceita??o entre os atletas. Logo, a produ??o de uma bebida energ?tica e funcional para atletas ? favor?vel e o desenvolvimento de novos produtos envolvendo o jamel?o como mat?ria-prima devem ser incentivados e explorados.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-05T19:32:12Z No. of bitstreams: 1 2012 - Gabriela Viana da Silva.pdf: 1385561 bytes, checksum: ebedf6cb2382daee2a3bf246edc9848f (MD5) / Made available in DSpace on 2017-04-05T19:32:12Z (GMT). No. of bitstreams: 1 2012 - Gabriela Viana da Silva.pdf: 1385561 bytes, checksum: ebedf6cb2382daee2a3bf246edc9848f (MD5) Previous issue date: 2012-03-27 / CAPES / The sheep milk production in Brazil is a relatively new activity, whose production is directed towards the manufacture of cheeses, yogurts and other products. Therewith a deficit of scientific papers related to this activity. Considered an excellent substrate, many pathogens can be transmitted to humans through consumption of milk and its derivatives, including Staphylococcus spp., one of the main agents involved in outbreaks of food poisoning. Moreover, the increasing of antimicrobial resistance is becoming a global public health problem. Within this problematic, this study aimed to identify the species of Staphylococcus and its antimicrobial susceptibility profile of current use in human and veterinary medicine, isolated from milk of sheep origin from rural properties in the Meridional Agreste of Pernambuco. We identified 13 different species, three coagulase-positive and 10 coagulase-negative and two strains identified only as SCN, especially Staphylococcus aureus (29) followed by S. chromogenes (15) and S. intermedius (9) by its frequency. The determination of antimicrobial susceptibility by disk diffusion revealed high rates of resistance to penicillin (53.2%) and ampicillin (45.6%). The susceptibility to oxacillin was evaluated by the disk diffusion methods for oxacillin and cefoxitin, Screen Agar and determination of Minimum Inhibitory Concentration through tests of broth microdilution and agar, the latter two detected resistance in 24% and 6% of isolates, respectively. All isolates were negative for the presence of blaZ and mecA genes and was not observed a correlation between phenotypic and genotypic testing for resistance to beta-lactams. The results show that this species is a source of infection, through its products, Staphylococcus potentially pathogenic to humans. / A produ??o de leite ovino no Brasil ? uma atividade relativamente nova, cuja produ??o est? direcionada para a confec??o de queijos, iogurtes e outros derivados. Com isso h? uma defict de trabalhos cient?ficos ligados a esta atividade. Considerado um excelente substrato, muitos micro-organismos patog?nicos podem ser veiculados ao homem atrav?s do consumo de leite e seus derivados, entre eles Staphylococcus spp., um dos principais agentes envolvidos em surtos de intoxica??es alimentares. Al?m disso, o crescente aumento da resist?ncia aos antimicrobianos vem se constituindo um problema de sa?de p?blica global. Dentro desta problem?tica, o presente estudo objetivou identificar as esp?cies de Staphylococcus e seu perfil de suscetibilidade aos antimicrobianos de uso corrente em medicina humana e veterin?ria, isoladas de leite de origem ovina provenientes de propriedades rurais no Agreste Meridional de Pernambuco. Foram identificadas 13 esp?cies diferentes, sendo tr?s do grupo Staphylococcus coagulase-positivo e 10 de Staphylococcus coagulase-negativo e duas cepas identificadas apenas como SCN, destacando-se por sua frequ?ncia Staphylococcus aureus (29) seguida pelo S. chromogenes (15) e S. intermedius (9). A determina??o da suscetibilidade aos antimicrobianos pelo teste disco difus?o revelou elevados percentuais de resist?ncia ? penicilina (53,2%) e ampicilina (45,6%). A suscetibilidade a oxacilina foi avaliada atrav?s dos m?todos de disco-difus?o para oxacilina e cefoxitina, Screen Agar e determina??o da Concentra??o Inibit?ria M?nima atrav?s dos testes de Microdilui??o em Caldo e em Agar, tendo estes dois ?ltimos detectado resist?ncia em 24% e 6% dos isolados, respectivamente. Todos os isolados foram negativos para a presen?a dos genes blaZ e mecA, n?o tendo sido observada uma correla??o entre os testes fenot?picos e genot?picos para a resist?ncia aos beta-lact?micos. Os resultados obtidos evidenciam que esta esp?cie animal ? mais uma fonte de infec??o e veiculadora, atrav?s de seus produtos, de Staphylococcus potencialmente patog?nicos para o homem.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-10T19:01:38Z No. of bitstreams: 1 2012 - Luciana Silva de Mattos Moura.pdf: 1864669 bytes, checksum: adf72c5c555099f630fa5de4140203ef (MD5) / Made available in DSpace on 2017-04-10T19:01:38Z (GMT). No. of bitstreams: 1 2012 - Luciana Silva de Mattos Moura.pdf: 1864669 bytes, checksum: adf72c5c555099f630fa5de4140203ef (MD5) Previous issue date: 2012-03-21 / CAPES / Rice, corn and beans, biofortified or not constitute an important source of protein-calorie. The use of these raw materials in product development is an alternative to the contribution of food quality and safety. In consequence, the objective of this study was to characterize the physicochemical and rheological flour mixed pre-gelatinized by extrusion of rice, beans and corn for their application in developing other products like pasta for breads, cakes, biscuits and pasta pre-cooked .The concentration of the mixture prepared in this study was 30% corn, 35% bean and 35% rice. To analyze the results was developed a central composite rotational design (CCRD), and the data analyzed by response surface, with 17 treatments and three independent variables, which were the moisture of the dough prior to extrusion (16, 18, 21, 24; 26%), the temperature of the extrusion zone 3 (126, 140, 160, 180, 193 ? C) and rotation of the extruder screw (106, 120, 140, 160, 173 rpm). Analyses of expansion ratio and bulk density, water solubility index (WSI) and water absorption index (WAI), viscoamylographic properties. Besides the chemical composition, mineral profile and analysis of color (brightness, chromaticity a * and b *) of the best treatments. The values of radial expansion index ranged from 1.34 to 6.87, being the highest value found in T3 prepared with 140 ? C, 160rpm and 18% moisture. The moisture and temperature had a negative effect on the expansion, an increase in these two variables leads to a decrease in the expansion of the product. This parameter is one of the most important for the characterization of an expanded product of high quality. Lower moisture contents can lead to greater dextrinization of starch and increase the solubility of the mixture, then, treatments such as T3, showed high solubility. An increase in moisture lead to an increased water absorption, achieving the highest values in the conditions of temperature 180 ? C, 160 rpm rotation and 24% moisture (U). These conditions were also suitable for obtaining solutions of high viscosity and low tendency to retrogradation. The T3: 140 ? C, 160 rpm and 18%, T4: 180 ? C, 160 rpm and 18%, T5: 140 ? C, 120 rpm and 24%, T8, 180 ? C, 160 rpm and 24%; T10: 193 ? C, 140 rpm and 21% of moisture, were considered the best formulations and they were analyzed in terms of color, composition and mineral profile. The thermoplastic extrusion process affected the color of the flour due to non-enzymatic browning reactions that occur with the samples. Moreover, the beans BRS Pontal stood out to provide higher levels of proteins (21.34 g/100 g) and high levels of minerals, including iron in the sample (7.0 mg/100 g) when compared with the other raw materials while that treatment 8 also stood out for its high mineral content and good fiber intake (greater than 8.5 g/100g). It was concluded that flour T3, due to its expansion and better solubility in water, can be used for preparing snacks, and soluble flour, while the treatment 8 is to increase the viability soups, sauces, because of its high viscosity and low tendency to solidify, due to the retrogradation. / Arroz, milho e feij?o, biofortificados ou n?o constituem uma importante fonte cal?rica-prot?ica. O uso destas mat?rias primas no desenvolvimento de produtos ? uma alternativa na contribui??o da qualidade e seguran?a alimentar. Em consequencia, o objetivo desse trabalho foi caracterizar f?sico-qu?mica e reologicamente as farinhas mistas pr?-gelatinizadas por extrus?o de arroz, feij?o e milho visando a sua utiliza??o na elabora??o de outros produtos como massas para p?es, bolos, biscoitos e macarr?o pr?-cozido. A concentra??o da mistura foi de 30% de milho, 35% de feij?o e 35% de arroz. Para an?lise dos resultados foi desenvolvido um delineamento composto central rotacional (DCCR), sendo os dados analisados por superf?cie de resposta, com 17 tratamentos e 3 vari?veis independentes, sendo elas a umidade da massa antes da extrus?o (16; 18; 21; 24; 26%), a temperatura da 3? zona de extrus?o (126;140; 160; 180; 193 ?C) e a rota??o do parafuso da extrusora (106; 120; 140; 160; 173 rpm). Foram realizadas an?lises de ?ndice de expans?o e densidade aparente, ?ndices de solubilidade e absor??o em ?gua, propriedades viscoamilogr?ficas. Al?m da composi??o centesimal, perfil de minerais e an?lise de cor (luminosidade, cromaticidade a* e b*) dos melhores tratamentos. Os valores de ?ndice de Expans?o variaram de 1,34 a 6,87, sendo o maior valor encontrado no tratamento T3 elaborado com 140?C, 160rpm e 18% de umidade. A umidade e a temperatura tiveram um efeito negativo sobre a expans?o, um incremento nessas duas vari?veis leva a uma diminui??o na expans?o do produto. Esse par?metro ? um dos mais importantes para caracteriza??o de um produto expandido de alta qualidade. Baixos conte?dos de umidade podem levar a uma maior dextriniza??o do amido e aumentar a solubilidade da mistura, ent?o, tratamentos como o T3, apresentaram solubilidade elevada. Um aumento da umidade levou a um aumento da absor??o em ?gua, alcan?ando aos maiores resultados com as condi??es de 180?C de temperatura, 160 rpm de rota??o e 24% de umidade. Essas condi??es tamb?m foram ideais para obten??o de solu??es de viscosidade elevada e baixa tend?ncia a retrograda??o. Os tratamentos T3: 140?C, 160 rpm e 18%; T4: 180?C, 160 rpm e 18%; T5: 140?C, 120 rpm e 24%; T8; 180?C, 160 rpm e 24%; T10: 193?C, 140 rpm e 21% de umidade, foram considerados as melhores formula??es e a eles foram realizadas an?lises de cor, composi??o centesimal e perfil de minerais. A colora??o das farinhas foi afetada com a extrus?o devido a rea??es de escurecimento n?o enzim?tico que acontecem com as amostras. O feij?o BRS Pontal se destacou por fornecer maiores teores de prote?nas (21,34g/100g) e elevado teor de minerais, inclusive ferro na amostra (7,0 mg/100g) quando comparado com as outras mat?rias-primas enquanto que o tratamento 8 se destacou pelo seu alto conte?do de minerais e por bom aporte de fibra (acima de 8,5g/100g). Conclui-se que a farinha T3, por apresentar melhor qualidade de expans?o e solubilidade pode ser utilizada na elabora??o de snacks e farinhas sol?veis, enquanto o tratamento T8 tem a viabilidade para incrementar sopas cremosas, molhos, por sua alta viscosidade e baixa tend?ncia a endurecer pela retrograda??o.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-18T18:54:16Z No. of bitstreams: 1 2012 - Abmael da Silva Cardoso.pdf: 1600160 bytes, checksum: 714351549deda5ed89c5e1ae3f665e30 (MD5) / Made available in DSpace on 2017-04-18T18:54:16Z (GMT). No. of bitstreams: 1 2012 - Abmael da Silva Cardoso.pdf: 1600160 bytes, checksum: 714351549deda5ed89c5e1ae3f665e30 (MD5) Previous issue date: 2012-01-27 / CAPES / The production of beef cattle in Brazil is responsible for much of the anthropogenic emission of greenhouse gases (GHG) emissions, especially methane from enteric fermentation and nitrous oxide from animal excretion. Changes in pasture management cattle diets may reflect a reduction in greenhouse gas emissions per unit of product produced. The objectives of this study were to simulate the effect of emission of greenhouse gases at different levels of intensification of beef production in Brazil, applying appropriate emission factors, and to assess the effect of changes in soil carbon stocks on the carbon balance. Four scenarios were established: number 1 - animals spent the entire cycle in areas of degraded pastures and extensive system; 2 - the animals spent the entire cycle on improved pastures but under an extensive system; 3 - the animals were raised on extensive improved pastures and supplemented in growing and fattening systems; and 4 - the animals were raised on pastures with intensive finishing in feedlots. The estimates of the GHG emissions were based on Brazilian studies of the zootecnic characteristics for each scenario. Using the methodology of the IPCC Tier 2 in the Scenario 2, the annual amount of CO2 emitted per carcass produced was 35.47 % lower than scenario 1; less than 18.85% in scenario 3 compared to scenario 2; and 19.6% lower in scenario 4 compared to scenario 3. Thus the intensification of production systems reduced the carbon emission per unit of product. Among the different factors used to compute the GHG balance, the application of Brazilian originated factors showed lower emissions per kg of product, and the methodology that uses the level of detail 2 of IPCC the highest. When the carbon sequestered by the soil was included in the balance, the mitigation values increase to 83.92% when comparing scenario 1 with 4, pointing to an even greatest mitigation potential per unit of product. The association between intensification and pasture recovery with carbon sequestration by soil presented a mitigation potential from 14.91 to 83.92% of emissions per unit of product. / A produ??o de bovinos de corte ? respons?vel no Brasil por grande parte da emiss?o de gases de efeito estufa (GEE), especialmente metano pela fermenta??o ent?rica dos animais e ?xido nitroso pela excre??o. Mudan?as no manejo e alimenta??o de animais bovinos podem repercutir numa redu??o das emiss?es destes gases por unidade de produto produzida. O objetivo deste trabalho foi verificar o efeito da emiss?o de gases de efeito estufa em diferentes n?veis de intensifica??o da pecu?ria de corte no Brasil aplicando diferentes fatores de emiss?o, bem como avaliar o efeito do sequestro de carbono sobre o balan?o de carbono. Quatro cen?rios foram estabelecidos: no primeiro os animais passavam todo o ciclo em ?reas com pastagens degradadas e sistema extensivo; no segundo os animais tinham o ciclo completo em pastagens resolutivas e sistema extensivo; no terceiro os animais eram criados em sistema extensivo em pastagens melhoras e com suplementa??o na recria e engorda; e no quarto sistema os animais eram criados em pastagens manejadas intensivamente com engorda em confinamento. A emiss?o de GEE para cada cen?rio foi calculada em fun??o das caracter?sticas zoot?cnicas e com base em estudos nacionais. Foi utilizada a metodologia do IPCC Tier 2 para o Cen?rio 2, a quantidade anual de CO2 emitido por carca?a produzida foi 35,47% menos em rela??o ao cen?rio 1, menos 18,85% no cen?rio 3 em rela??o ao cen?rio 2, e 19,6% menos no cen?rio 4 em rela??o ao cen?rio 3. Portanto a intensifica??o da bovinocultura de corte reduz a pegada de carbono da carne bovina. Entre os diferentes fatores usados para o balan?o de GEE o com fatores nacionais apresentou menor emiss?o por quilo de produto, e o m?todo com o n?vel de detalhamento 2 do IPCC a maior emiss?o. Quando inclusos os valores de carbono sequestrado pelo solo no balan?o, os valores de mitiga??o aumentaram para 83,92% entre o cen?rio 1 e 4, apontando para um potencial de mitiga??o ainda maior por unidade de produto. A associa??o entre intensifica??o e recupera??o das pastagens com sequestro de carbono pelo solo apresentou potencial de mitiga??o entre 14,91 e 83,92% das emiss?es por unidade de produto.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-19T20:11:40Z No. of bitstreams: 1 2013 - Juliano Bahiense Stafanato.pdf: 777062 bytes, checksum: 5c25a6af1b707f5ea33fcb9f45c94a6a (MD5) / Made available in DSpace on 2017-04-19T20:11:40Z (GMT). No. of bitstreams: 1 2013 - Juliano Bahiense Stafanato.pdf: 777062 bytes, checksum: 5c25a6af1b707f5ea33fcb9f45c94a6a (MD5) Previous issue date: 2013-02-21 / CAPES / This study aimed to evaluate the dynamics of nitrogen losses by volatilization of ammonia from urea fertilizers pelletized with different micronutrients (zinc, copper and boron), and to evaluate possible residual effect of these nutrients as well as the effect on the growth and development of corn (Zea mays) plants. The studies took place in a greenhouse at the experimental area of the Soils Department of Federal Rural University of Rio de Janeiro. The soil used in this study was sampled from surface horizon of a Fragiudult soil and had sandy texture. For testing volatilization and residual effect of nitrogen two doses (100 and 200 kg ha-1) were applied. The fertilizers were evaluated for N losses for a period of 21 days. After the period of the N losses evaluation, corn seeds were planted in the same soil, to assess the residual effect of these pelletized fertilizer containing micronutrients. After these two experiments, they were selected, among the 15 pelletized urea formulas, 9 products that showed the best results, especially those which resulted in decreasing N losses by volatilization. These products were then evaluated for their effect on growth and development of corn plants, using the variety Sol da Manh?. The amount of the micronutrient boron in the pelletized urea positively influenced the reduction of N losses by NH3 volatilization, particularly when in higher concentration (4.0% B), reducing N losses by 50% (rate of 100 kg ha-1) and 64 % (dose of 200 kg ha-1) compared to the pearly urea. In general, the pelletized urea containing micronutrients, especially B, single or associated with Zn and Cu, showed to be a promising alternative for new fertilizers, with the goal of reducingN losses by volatilization. There was no effect of the different nitrogen fertilizers application as for increasing residual N in the soil. The application of the pelletized urea containing Zn, Cu and B micronutrients, single and / or associated, increased their quantities in the soil. The largest additions of the micronutrients Zn, Cu and B in the soil, using the pelletized urea, consequently, reflected in greatest amounts of these elements in the maize plant. The addition of zinc by application of pelletized urea did not show positive effect in the growth of corn plant as expected. Possibly, due to zinc quantities in the soil sufficient to supply the plants requirement. The presence of boron in the pelletized urea influenced the accumulation of N in the plants, especially for B concentrations in the fertilizer above 2.0 %. / Este trabalho teve como objetivo avaliar a din?mica de perdas de nitrog?nio por volatiliza??o da am?nia oriundo de fertilizantes pastilhados de ureia com diferentes micronutrientes (zinco, cobre e boro), avaliando o poss?vel efeito residual destes nutrientes como tamb?m seu efeito sobre o crescimento e desenvolvimento de plantas de milho (Zea mays). Os estudos foram realizados em casa de vegeta??o localizada na ?rea experimental do Departamento de Solos da UFRRJ. O solo utilizado neste trabalho foi proveniente de um horizonte superficial de um Planossolo H?plico (textura arenosa). Para o ensaio de volatiliza??o e efeito residual foram utilizados duas doses de N (100 e 200 kg ha-1), onde os diferentes fertilizantes foram avaliados quanto as perdas de N por um per?odo de 21 dias. Ap?s o per?odo de avalia??o das perdas de N foram plantadas no mesmo solo, sementes de milho com intuito de avaliar o efeito residual destes fertilizantes pastilhados contendo micronutrientes. Ao t?rmino destes dois ensaios, foram ent?o selecionados dentre os 15 pastilhados de ureia, 9 produtos que apresentaram os melhores resultados, principalmente aqueles que resultaram em maiores redu??es nas perdas de N por volatiliza??o, que foram ent?o avaliados quanto ao seu efeito no crescimento e desenvolvimento de plantas de milho, variedade Sol da Manh?. O micronutriente boro presente nos pastilhados de ureia influenciaram positivamente na redu??o das perdas de N-NH3 por volatiliza??o, principalmente quando presente na maior concentra??o (4,0% B), reduzindo as perdas de N em 50% (dose de 100 kg ha-1) e em 64% (dose de 200 kg ha-1) as perdas em rela??o a ureia perolada. De forma geral, os pastilhados de ureia contendo micronutrientes, principalmente B de forma isolada e/ou associado com Zn e Cu demonstraram ser uma alternativa promissora de novos fertilizantes com objetivo de reduzir as perdas de N por volatiliza??o. N?o houve efeito da aplica??o dos diferentes fertilizantes nitrogenados em aumentar as quantidades residuais de N no solo. A aplica??o dos pastilhados de ureia contendo os micronutrientes Zn, Cu e B isolados e/ou associados aumentaram as quantidades destes no solo. As maiores adi??es dos micronutrientes Zn, Cu e B no solo via ureia pastilhada refletiram-se, consequentemente, em maiores quantidades destes elementos na planta de milho. A adi??o de zinco via aplica??o de ureia pastilhada n?o apresentou efeito positivo em incrementar o crescimento da planta de milho como esperado. Possivelmente, pois as quantidades de zinco no solo foram suficientes para suprir as necessidades das plantas. A presen?a de boro nos pastilhados de ureia influenciaram o ac?mulo de N nas plantas, principalmente para concentra??es de B no fertilizante acima de 2,0%.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-05T18:33:54Z No. of bitstreams: 1 2010 - Frederico Santos Machado.pdf: 2164167 bytes, checksum: 28047d32a367720ee18ef9cf4c58be45 (MD5) / Made available in DSpace on 2017-05-05T18:33:54Z (GMT). No. of bitstreams: 1 2010 - Frederico Santos Machado.pdf: 2164167 bytes, checksum: 28047d32a367720ee18ef9cf4c58be45 (MD5) Previous issue date: 2010-05-27 / The hydric erosion is one of main environmental impact in Central Amazonia region, causing serious economic consequences for implantation and recovery of operational locations of PETROBRAS S/A oil and natural gas exploration and production sites. This study was carried through in Petroliferous Province of Urucu, municipality of Coari (AM). The objective was to quantify soil loss (SL) and runoff (SD) in different soil classes and under vegetal coverings using a portable rain simulator. Sixteen batteries of tests were done, eight batteries for each soil class (Fluventic Dystrustepts e Kanhaplic Haplustults). For each battery three repetitions had been made in the following covers: forest, forest without litter and grass. The results of Tukey test at 0.05 level showed that soil classes were not significantly different between themselves. On the other hand, the organic carbon percentage and the soil bulk density had greatest importance for the soil loss. These attributes, plus fine sand and clay, influenced most in the runoff. It was also possible to observe that runoff was the attribute of highest correlation with soil loss. The conversion of forest areas into grass increased, at least, four times the water runoff, changing it from 14.2 mm to 57.7 mm in the grass area, and, at least, two times loss of soil mass, achieving the value of 35.68 t.ha-1.year-1 in the grass area. Although with these values, grassy areas only differed significantly from the forest areas in the runoff. The runoff values tend to increase twofold when litter is removed from the forest soils, while the soil losses increased 40%. The attributes that were important for the soil classes were the same for cover types, however with differences in the attribute clay content for soil loss, and coarse sand for runoff. For the studied treatments, the attribute that showed highest correlation with soil loss was runoff. / A eros?o h?drica ? um dos principais impactos ambientais na regi?o da Amaz?nia Central, causando s?rias conseq??ncias, inclusive econ?micas, para a implanta??o e recupera??o de loca??es operacionais de explora??o e produ??o de petr?leo e g?s natural da PETROBRAS S/A. Este estudo foi realizado na Prov?ncia Petrol?fera de Urucu, munic?pio de Coari (AM) e teve como objetivo quantificar a perda de solo (PS) e o escoamento superficial (ES) em diferentes grupos de solo e coberturas vegetais, utilizando um simulador de chuva port?til. Foram efetuadas 16 baterias de testes, sendo 4 baterias para cada grupo de solo (ARGISSOLO AMARELO Al?tico, ARGISSOLO VERMELHO-AMARELO Al?tico, CAMBISSOLO H?PLICO Al?tico e CAMBISSOLO H?PLICO Tb Distr?fico). Em cada bateria foram realizados tr?s repeti??es nas seguintes coberturas: floresta, floresta sem serrapilheira e gram?nea. As classes de solo n?o diferiram significativamente entre si ao n?vel de 5%, segundo o teste de Tukey. Para a PS, a porcentagem de carbono org?nico e a densidade do solo t?m grande import?ncia para os grupos de solo. Esses atributos, mais a areia fina e argila influenciaram o ES. Tamb?m foi poss?vel observar que o escoamento foi o atributo com maior coeficiente de correla??o com a perda de solo. A convers?o das ?reas de floresta em gram?nea aumentou em no m?nimo quatro vezes a l?mina de ?gua escoada, passando de 14,2 mm para 57,7 mm na gram?nea e, no m?nimo, duas vezes a massa de solo perdida, chegando a 35,8 t.ha-1.ano-1 na gram?nea. Apesar desses valores, as ?reas cobertas por gram?neas apenas diferiram significativamente das ?reas de florestas em rela??o ao ES. Quando se retira a serrapilheira em solos florestais, os valores de escoamento dobram, enquanto que as perdas aumentam em 40%. Os atributos que tiveram import?ncia para as classes de solo foram os mesmos para os tipos de coberturas, por?m com diferen?as no atributo teor de argila para a perda de solo e no teor de areia grossa para o escoamento. Para os tratamentos estudados, o escoamento continua sendo o atributo com maior coeficiente de correla??o com a perda.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-23T19:49:38Z No. of bitstreams: 1 2014 - Rafael Passos Rangel.pdf: 2601166 bytes, checksum: 8cd9cbb0ff858a2d7c7c31027eaf3efb (MD5) / Made available in DSpace on 2017-05-23T19:49:38Z (GMT). No. of bitstreams: 1 2014 - Rafael Passos Rangel.pdf: 2601166 bytes, checksum: 8cd9cbb0ff858a2d7c7c31027eaf3efb (MD5) Previous issue date: 2014-02-26 / CAPES / Root morphology is a major factor related to the efficiency of nutrient acquisition. For this reason, this work compared this characteristic in three contrasting rice varieties: IAC 47 (improved variety) and two traditional varieties cultivated in the state of Maranh?o (Piau? and Manteiga originated in an environment with low nutrient input). These varieties were subjected to a low N-NH4+ supply and analyzed for the root morphology parameters, expression of ammonium high affinity transport system (OsAMT1.1~1.3) and GS activity in three segments of the root system. It was also determined the soluble fractions and total nitrogen in the different segments of the plants (leaves, sheaths and roots) to verify the metabolic alterations as a result of low ammonium input. The GS activity was higher in the second segment in the Manteiga and IAC-47 varieties compared to Piau?, in the other segments. A similar result was observed in the Manteiga variety in the third segment (bottom of the root system) submitted to NH4+ resupply. When grown without NH4+, the Manteiga variety showed higher OsAMT1.3 expression in the lower segment of the root system, and greater root growth, indicating a possible involvement of this transporter in the control of root morphology in rice plants. There was lower expression of OsAMT1.1 and OsAMT1.2 unlike OsAMT1.3 but being distributed to other segments of the root system. In resupply with NH4+ (38 DAG) there was repression of ammonium transporters in the bottom (PI) of the root system and increased expression of OsAMT1.2 the median part (PM) in Piau? variety. In the upper part of the roots (PS) higher levels of ammonium transporter expression was observed in the IAC-47, and Manteiga. This difference in expression between varieties originated from regions with low N availability (Piau? and Manteiga) and improved IAC-47 is an indication that under conditions of limited N, the highest expression of OsAMT1.3 may be associated with an increase in morphological parameters. / A morfologia radicular ? uma das principais caracter?sticas relacionadas ? efici?ncia de aquisi??o de nutrientes em plantas. Deste modo, variedades de arroz contrastantes: uma melhorada, (IAC-47) e duas variedades locais do Maranh?o: (Piau? e Manteiga, origin?rias de cultivos com baixa disponibilidade de nutrientes) foram submetidas a um baixo suprimento de N-NH4+ e avaliadas quanto aos par?metros de morfologia radicular, express?o dos transportadores de alta afinidade para am?nio (OsAMT1.1~1.3) e atividade de GS em tr?s segmentos do sistema radicular. Tamb?m foram determinadas as fra??es sol?veis e o nitrog?nio total nas diferentes partes da planta (folha, bainha e raiz) de forma a acompanhar altera??es metab?licas em resposta a baixa disponibilidade de am?nio. A atividade da GS foi maior na segunda coleta, nas variedades Manteiga e IAC-47 em rela??o a Piau?, nas demais coletas. Resultado semelhante foi observado na parte inferior do sistema radicular, para a variedade Manteiga na terceira coleta com ressuprimento com am?nio. Quando cultivada sem suplementa??o amoniacal, a variedade Manteiga apresentou maior express?o do OsAMT1.3 na parte inferior (PI) do sistema radicular, e maior crescimento de ra?zes, indicando um poss?vel envolvimento desse transportador com o controle da morfologia radicular de plantas de arroz. Houve menor express?o do OsAMT1.1 e OsAMT1.2 diferentemente do OsAMT1.3, por?m distribuindo-se a outros segmentos do sistema radicular. No ressuprimento com am?nio aos 38 dias ap?s a germina??o (38 DAG) houve repress?o dos transportadores de am?nio na parte inferior (PI) do sistema radicular e aumento de express?o do OsAMT1.2 na parte mediana (PM) para a variedade Piau?. Na parte superior das ra?zes (PS) os maiores n?veis de express?o dos transportadores de am?nio de alta afinidade foram observados para as variedades IAC-47 e Manteiga. Esta diferen?a de express?o entre variedades oriundas de regi?es com baixa disponibilidade de N (Piau? e Manteiga) e a variedade melhorada IAC-47 ? um indicio que sob condi??es limitantes de N, a maior express?o do OsAMT1.3 pode estar associado com incremento nos par?metros morfol?gicos.