Univ. Pedagógica y Tecnológica de Colombia, Diss.--Tunja, 2005.

Submitted by Inácio de Oliveira Lima Neto (inacio.neto@inpa.gov.br) on 2018-07-13T18:47:44Z No. of bitstreams: 2 dissertacao_Luis_versao_final.pdf: 15102445 bytes, checksum: 19cf08353dc3d5342446786c90e35595 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-07-13T18:47:44Z (GMT). No. of bitstreams: 2 dissertacao_Luis_versao_final.pdf: 15102445 bytes, checksum: 19cf08353dc3d5342446786c90e35595 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-05-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Ceratopogonidae family possesses four hematophagics genus: Forcipomyia, Leptoconops, Austroconops and Culicoides. The Culicoides are insects with 3mm in length, the female are vectors of helminths, protozoan and virus. The main arboviruses transmitted are Oropouche virus, endemic of amazon basin and Bluetongue Virus, which affects both wildlife and domestic livestocks. The convenience collections were done on Alvorada do Oeste, Buritis, Cacoal, Costa Marques, Espigão do Oeste, Guajará-Mirim, Pimenta Bueno, São Francisco Guaporé and Porto Velho municipalities, in Rondônia state through HP light traps between 18:00 and 06:00. Systematic collections were made in Porto Velho municipality on forest and pasture environments. Were collected 2,196 Culicoides (1,515 females and 681 males) distributed throughout 43 species and 27 morfotypes. The species most frequent were Culicoides insignis (n=1,594; 72.59%), C. foxi (n=76; 3.46%), C. hildebrandoi (n=53; 2.41%), C. leopoldoi (n=44; 2%), C. ocumarensis (n=34; 1.55%), C. pusillus (n=29; 1.32%) and C. glabrior (n=28; 1.28%). There were 37 news records of species in Rondônia and three for Brazil. The municipalities with greatest richness were Porto Velho (56), Cacoal (26) e Costa Marques (14). The municipalities with lowest richness were Espigão do Oeste (4), Buritis (3) and Alvorada do Oeste (2). Species with greatest distribution were C. foxi and C. leopoldoi. In Porto Velho were collected 1,773 individuals (1,179 female and 594 males), collected 228 individuals and 51 species in forest, and collected 1,545 individuals and 19 species in pasture. The most abundant species were C. insignis (n=1,472; 83%), C. foxi (n=45; 2.5%), C. glabrior (n=25; 1.4%) and C. ocumarensis (n=23; 1.3%). The forest presented most richness (41 species) and pasture presented greatest abundance (1,545 individuals). In Pasture the most abundant species were C. insignis (1,457-94.30%), C. foxi (34-2.20%) and C. ocumarensis (14-0.90%), and Forest the most abundant species were C. Glabrior (25-10.96%), C. insignis (15-6.57%) e C. tetrathyris (15-6.57%). Diversity of species and eveness on Forest environment were greatest than Pasture environment. There was significant statistical difference (p=0.02) on species composition per environment. Diagnoses of some individuals of Rondônia were made. The findings of species of Culicoides on Rondônia now contribute to the total of 46 species, representing 36.8% of amazon species. The species C. Darlingtonae, C. contubernalis e C. rodriguezi contribute for ampliation of geographic distribution this species and increase of amazon species fauna. The wide distribution of C. foxi and C. leopoldoi suggest that this species are ecletics for ecotypes and blood meal sources (chicken, livestock and human). The high abundance of C. insignis indicates that feeding behavior on mammals can be one of the factors contributing to the high number of individuals on light traps when placed near blood meal sources. Low number of individuals of C. paraensis on rural areas suggests that this specie is little attracted to light traps due to its diurnal or anthropophilic and urban habit that this species has. In Porto Velho, greatest abundance of C. insignis on Pasture can is related to the wet and muddy substrate with decaying organic matter, which favors the development of immature. The greatest diversity in forest can be explained by water bodies, wetlands, undergrowth, fruit peels present in this breeding sites, which makes it conducive to the proliferation and maintenance of Culicoides species. The diagnosis of the main morphotypes shows differences and similarities in relation to species already described, indicating possible new species for the state of Rondônia. / A família Ceratopogonidae possui quatro gêneros hematófagos: Forcipomyia, Leptoconops, Austroconops e Culicoides. Os Culicoides são insetos com até 3 mm de tamanho, as fêmeas são vetores de helmintos, protozoários e vírus. As principais arboviroses transmitidas são Oropouche, endêmica da bacia amazônica e Vírus da Língua Azul, que acomete bovinos silvestres e domésticos. As coletas de conveniência foram realizadas nos municípios de Alvorada do Oeste, Buritis, Cacoal, Costa Marques, Espigão do Oeste, Guajará-Mirim, Pimenta Bueno e São Francisco Guaporé, no estado de Rondônia, por meio de armadilhas luminosas HP entre 18:00 e 06:00. As coletas sistemáticas foram feitas no município de Porto Velho nos ambientes de floresta e pasto. Foram capturados 2.196 indivíduos, (1.515 fêmeas e 681 machos), distribuídos em 43 espécies e 27 morfótipos. As espécies mais frequentes foram Culicoides insignis (n=1.594; 72,59%), C. foxi (n=76; 3,46%), C. hildebrandoi (n=53; 2,41%), C. leopoldoi (n=44; 2%), C. ocumarensis (n=34; 1,55%), C. pusillus (n=29; 1,32%) e C. glabrior (n=28; 1,28%). Houve 37 novos registros de espécies em Rondônia e três novos registros para o Brasil. Os municípios com maior riqueza foram Porto Velho (56), Cacoal (26) e Costa Marques (14). Os municípios com menor de número de espécies foram Espigão do Oeste (4), Buritis (3) e Alvorada do Oeste (2). As espécies com maior distribuição foram C. foxi e C. leopoldoi. No município de Porto Velho foram capturados 1.773 indivíduos (1.179 fêmeas e 594 machos), sendo coletados 228 espécimens e 51 espécies em floresta, e 1.545 indivíduos e 19 espécies em pasto. As espécies mais abundantes foram C. Insignis (1.472; 83%), C. foxi (45; 2,5%), C. glabrior (25; 1,4%) e C. ocumarensis (23; 1,3%). Floresta apresentou maior riqueza (41) e o pasto apresentou maior abundância (n=1.545). No pasto as espécies mais abundantes foram C. insignis (1.457-94,30%), C. foxi (34-2,20%) e C. ocumarensis (14-0,90%), e em floresta as mais abundantes foram C. glabrior (25-10,96%), C. Insignis (15 6,57%) e C. tetrathyris (15-6,57%). A diversidade de espécies e a homogeneidade foram maiores em área de floresta do que o ambiente pasto. Houve diferença estatística significativa (p=0,02) na composição de espécies por ambiente. Foram realizadas diagnoses de alguns morfótipos de Rondônia. O achado de espécies de Culicoides em Rondônia contribui agora para o total de 46 espécies, representando 36,8% das espécies amazônicas. As espécies C. darlingtonae, C. contubernalis e C. rodriguezi contribuem para a ampliação da distribuição geográfica dessas espécies e o incremento da fauna de espécies amazônicas. A ampla distribuição de C. foxi e C. leopoldoi sugere que essas espécies são ecléticas às opções de ecótopos e fontes de repasto (galinhas, gados e humanos). A alta abundância de C. Insignis indica que o comportamento alimentar sobre os mamíferos pode ser um dos fatores que contribui para o elevado número de indivíduos em armadilhas luminosas, quando colocadas próximas a fontes de repasto. O baixo número de C. paraensis na zona rural sugere que essa espécie é pouco atraída às armadilhas luminosas devido a seu hábito diurno ou ao hábito antropofílico e urbano que essa espécie apresenta. Em Porto Velho, a maior abundância de C. insignis em pasto pode está relacionado ao substrato úmido e enlameado com matéria orgânica em decomposição, que favorece o desenvolvimento de imaturos. A maior diversidade em floresta pode ser explicada pelos corpos d’água, brejos, serrapilheira, cascas de frutas presentes neste ecótopo, que torna propício à proliferação e manutenção de espécies de Culicoides. A diagnose dos principais morfótipos mostra diferenças e semelhanças em relação às espécies já descritas, indicando possíveis espécies novas para o estado de Rondônia.

Orientador: Mário De Beni Arrigoni / Resumo: Objetivo do estudo foi avaliar a análise dos isótopos estáveis (13C, 2H, 16O e 15N) da carne na caracterização dos sistemas de terminação de bovinos Nelore criados na mesma propriedade. Três sistemas de terminação de bovinos de corte foram escolhidos, sendo estes: confinamento, semi-confinamento e pasto. Vinte amostras de do M. Semitendinosus de cada sistema foram coletadas para análise. Os dados isotópicos dos músculos com e sem extração de gordura foram submetidos à análise de univariada (ANOVA) e multivariada (MANOVA). O Carbono-13 foi diferente (P ≤ 0,001) entre os sistemas de terminação. O Nitrogênio-15 foi maior (P ≤ 0,001) para as amostras de confinamento, em comparação às amostras de semi-confinamento e pasto. Os elementos 2H e 16O não foram diferentes (P ˃ 0,05). O método de extração de gordura das amostras de carne aumentou a variabilidade dos resultados, diminuindo a distinção dos sistemas produtivos. A combinação dos elementos significativos obteve um total percentual de variação de 87,4% nos dois primeiros componentes diferenciando os três sistemas e pela análise de discriminante linear determinou uma taxa global correta de classificação de 98,3% e uma taxa de validação cruzada de 95,0%. A razão isotópica dos elementos Carbono e Nitrogênio com e sem extração de gordura, permitem diferenciar e certificar as amostras de carne entre os sistemas de confinamento, semi-confinamento e pasto com alta precisão em mesma propriedade. / Doutor

Submitted by RODOLFO MACIEL FERNANDES null (rodolfo_fernandes@hotmail.com) on 2018-01-29T13:55:27Z No. of bitstreams: 1 Tese_29_01_2018.pdf: 1325437 bytes, checksum: 2ee40b57e2b708a74c6c45aa8dce5d74 (MD5) / Approved for entry into archive by Karina Gimenes Fernandes null (karinagi@fcav.unesp.br) on 2018-01-30T11:56:43Z (GMT) No. of bitstreams: 1 fernandes_rm_dr_jabo.pdf: 1312368 bytes, checksum: 89032e00f15eaa6eff8cfec58f4e2ee2 (MD5) / Made available in DSpace on 2018-01-30T11:56:43Z (GMT). No. of bitstreams: 1 fernandes_rm_dr_jabo.pdf: 1312368 bytes, checksum: 89032e00f15eaa6eff8cfec58f4e2ee2 (MD5) Previous issue date: 2017-10-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivou-se com a presente pesquisa avaliar se o consumo de nitrato encapsulado por bovinos zebuínos nas condições tropicais em pastejo da recria ao abate altera os parâmetros ruminais, consumo, mitiga metano, altera o desempenho, a qualidade da carne e ocasiona resíduo na carne. Foram utilizados 96 animais da raça Nelore com idade entre 7 e 8 meses e 197 ± 15,3 kg de peso corporal (PC) inicial, distribuídos aleatoriamente em blocos completos ao acaso aos tratamentos para a avaliação de desempenho, sendo que desses, 24 animais foram utilizados para a avaliação da emissão de metano. Também foram utilizados 12 animais contemporâneos dos animais de desempenho com fistulados no rúmen e PC inicial de 202 ± 6,22 kg para a quantificação dos parâmetros fermentativos, distribuídos aleatoriamente em blocos completos, totalizando 108 animais. Foram avaliados dois tratamentos, o primeiro denominado controle (suplemento sem nitrato, com equivalente proteico substituído por ureia) e o segundo, suplemento com nitrato (47g NO3-/100 kg PC). O experimento foi dividido em três fases: seca (07/2014 a 11/2014), águas (11/2014 a 05/2015) e terminação (05/2015 a 09/2015). Na fase de seca, a suplementação com nitrato reduziu a concentração de NAR (P≤0,04) em média 39%, 6, 12 e 18 horas após a suplementação. Na fase de águas e terminação, o nitrato ocasionou menor concentração de NAR 6 horas após a suplementação na proporção de 29,62% e 60,73%, respectivamente (P=0,06). O uso de nitrato aumento o consumo de forragem dos animais apenas na fase de águas (P=0,04) em 1,30kg/dia. Nas fases de seca e águas, a suplementação com nitrato tendeu (P≤0,11) a reduzir a emissão de metano em aproximadamente 16,57% e 14,59%, respectivamente. Apenas na fase de terminação houve efeito do tratamento (P=0,03) sobre o ganho de peso, com médias de 0,901kg/dia para animais recebendo controle e 0,998kg/dia para animais suplementados com nitrato, proporcionando animais com peso superior ao abate (492kg para animais controle e 521kg para animais nitrato) (P=0,05). Não houve efeito dos tratamentos no peso de carcaça final (P=0,44), com médias de 297kg e 303kg para animais controle e nitrato, respectivamente. A carcaça dos animais controle tiveram maior espessura de gordura subcutânea (3mm) em relação a nitrato (2,1mm) (P=0,08). Houve tendência em reduzir a intensidade de emissão (g/kg de carcaça) em 18% nos animais nitrato(P=0,11). Não houve diferença entre os tratamentos para qualidade e cor da carne (P≥0,32) e também no perfil de ácidos graxos (P≥0,50). O uso de nitrato não proporciona resíduo de nitrato na carne (P=0,77). Conclui-se que o consumo de nitrato encapsulado por bovinos zebuínos nas condições tropicais em pastejo da recria ao abate pode alterar os parâmetros ruminais, o consumo de forragem e tende a reduzir a emissão de metano de acordo com a qualidade da forragem. O consumo de nitrato encapsulado também proporciona peso superior ao abate, sem alterar o peso de carcaça final, além de não alterar a qualidade ou deixar resíduo na carne. / The objective of this research was to evaluate if the intake of nitrate encapsulated by zebu cattle in the tropical conditions under pasture grazing changes the ruminal parameters, consumption, mitiga methane, changes in performance, meat quality and cause s residue in meat. A total of 96 Nellore animals aged 7 to 8 months and 197 ± 15.3 kg of body weight (BW) were randomly assigned in randomized complete blocks to treatments for performance evaluation, of which 24 animals were used for the evaluation of met hane emission. We also used 12 contemporary animals from performance animals with rumen fistulae and initial CP of 202 ± 6.22 kg for the quantification of fermentative parameters, randomly distributed in complete blocks, totaling 108 animals. Two treatment s were evaluated, the first one called control (supplement without nitrate, with protein equivalent substituted by urea) and the second supplement with nitrate (47g NO3 - / 100kg PC). The experiment was divided into three phases: dry (07/2014 to 11/2014), w ater (11/2014 to 05/2015) and termination (05/2015 to 09/2015). In the dry phase, nitrate supplementation reduced the RAN concentration ( P≤0.04 ) on average by 39%, 6, 12 and 18 hours after supplementation. In the water and termination phase, nitrate caused a lower concentration of RAN 6 hours after supplementation in the proportion of 29.62% and 60.73%, respectively ( P=0.06 ). The use of nitrate increased the forage intake of the animals only in the water phase ( P=0.04 ) in 1.30 kg / day. In the drought and w ater phases, nitrate supplementation tended to reduce methane emissions by approximately 16.57% and 14.59%, respectively ( P≤0.11 ). Only in the termination phase was treatment effect ( P = 0.03) on weight gain, with averages of 0.901 kg / day for animals rec eiving control and 0.988 kg / day for animals supplemented with nitrate, providing animals with higher XIV slaughter weight (492 kg for control animals and 521 kg for nitrate animals) ( P=0.05 ). There was no effect of treatments on final carcass weight ( P=0.44 ) , with averages of 297kg and 303kg for control and nitrate animals, respectively. The carcass of the control animals had a higher thickness of subcutaneous fat (3mm) in relation to nitrate (2.1mm) ( P=0.08 ). There was a tendency to reduce the emission intensity (g / kg of carcass) by 18% in nitrate animals ( P=0.11 ). There was no difference between the treatments for meat quality and color ( P≥0.32 ) and also in the fatty acid profile ( P≥0.50 ). The use of nitr ate does not provide nitrate residue in meat ( P=0.77 ). It can be concluded that the consumption of nitrate encapsulated by zebu cattle under tropical conditions under pasture grazing at slaughter can alter ruminal parameters, forage consumption and tends t o reduce methane emissions according to forage quality. The consumption of encapsulated nitrate also provides superior slaughter weight, without altering the final carcase weight, and does not alter the quality or leave residue in the meat. / 141007/2014-1

El estrés ejerce sus efectos sobre el organismo, no sólo a través de las vías de respuesta fisiológica, sino también a través de vías genéticas y epigenéticas. Muchos autores sostienen que el estrés es un factor clave para explicar el papel evolutivo del sexo en los organismos de modo reproductivo facultativo. Por lo tanto, es esperable que los mismos se crucen más frecuentemente bajo situaciones de estrés, facilitando la adaptación a ambientes cambiantes. Eragrostis curvula es un complejo polimórfico donde la mayoría de sus miembros se reproducen por apomixis, reproducción asexual a través de semillas, que conduce a la generación de progenies genéticamente idénticas a la planta madre. El objetivo de esta tesis fue determinar el efecto de diferentes factores que generan estreses genómicos sobre la expresión de la apomixis en pasto llorón, como el estrés hídrico, el cultivo in vitro, la poliploidización y la hibridación intraespecífica. Para ello, se analizaron sacos embrionarios de plantas de distintos genotipos de pasto llorón luego de haber sido sometidas a dichas condiciones. Además, se realizaron pruebas de progenie con marcadores moleculares y se analizó el nivel de metilación de los genomas luego de los diferentes tratamientos. Antes de evaluar el efecto de situaciones estresantes sobre el modo reproductivo fue necesario analizar la estabilidad del carácter a lo largo del periodo de floración, hallándose que el cv. Tanganyika INTA presenta una sexualidad promedio menor al 2 % en condiciones de invernáculo. Plantas del cv. Tanganyika INTA bajo condiciones de estrés por déficit hídrico mostraron un 14 % de sacos sexuales, indicando un incremento de expresión de la sexualidad respecto de las plantas control. Luego de un periodo de rehidratación mostraron una sexualidad residual del 5,3 %, indicando una disminución significativa de la misma, siendo, sin embargo, significativamente diferente del control. Se realizaron pruebas de progenie con marcadores RAPDs y se detectaron polimorfismos solamente en las plantas sometidas a estrés hídrico, aunque en una proporción menor a la esperada de acuerdo a los análisis citoembriológicos, indicando que no todos los sacos embrionarios sexuales producidos dan lugar a plantas viables. El cv. Tanganyika USDA no evidenció en ningún momento la capacidad de generar sacos sexuales, clasificándoselo como apomíctico obligado. El genotipo facultativo UNST1131 presentó una proporción de procesos sexuales del 18,5 % bajo condiciones de estrés hídrico. Sin embargo este valor no fue significativamente distinto al control (10 %), debido principalmente a la gran variabilidad observada. Para evaluar efectos mediados por ABA se realizaron ensayos de aplicación foliar en plantas del cv. Tanganyika INTA normalmente regadas. El análisis citoembriológico no permitió detectar diferencias significativas en el número de sacos sexuales en relación con el control, descartándose momentáneamente a la concentración de esta hormona como mediadora del efecto generado por estrés. También se analizó el efecto del cultivo in vitro realizando diferentes ensayos en los que se varió el tipo de explanto, el medio de cultivo y la duración de los mismos. Se evaluaron los cultivares Tanganyika USDA y Tanganyika INTA. Solo uno de los ensayos (exposición a medios selectivos) generó un efecto significativo sobre el número de sacos sexuales producidos, que incrementaron, demostrando una cierta plasticidad del carácter en situaciones de estrés. Estos resultados indicarían que situaciones de estrés previas y durante la etapa de floración podrían estar regulando la expresión de la sexualidad en genotipos apomícticos facultativos de pasto llorón. Es evidente que en los cvs. Tanganyika USDA, Tanganyika INTA y UNS1131 expresan diferentes niveles de apomixis/sexualidad, desde cero a 33%. Por otro lado, este estudio permitió demostrar que no solo las condiciones externas promueven estreses genómicos que alteran la expresión de la apomixis en pasto llorón. Condiciones como la poliploidización y la hibridación intraespecífica también afectan al modo reproductivo. El análisis de la expresión de la apomixis a través del tiempo en dos híbridos (105 y 60) obtenidos a partir de la cruza entre materiales contrastantes para el modo reproductivo mostró diferencias en la expresión del carácter. El primero (105) mostró un comportamiento errático en las proporciones de procesos apomíctico/sexuales, con estabilización del carácter tendiente a una relación 1:1 mientras que el otro, (60) presentó solo sacos sexuales en las dos primeras floraciones y una pequeña proporción de sacos apomícticos en la tercera. Los resultados obtenidos en las pruebas de progenie mostraron correlación con los observados por estudios citoembriológicos. Dada la relación entre la apomixis y el ambiente, podría especularse que los genes involucrados en el modo reproductivo son controlados por factores epigenéticos como la metilación del ADN. Se realizaron análisis comparativos sobre los genomas (AFLP) y epigenomas (MSAP) de varios grupos de plantas con el fin de establecer el efecto de estreses genómicos sobre el genoma y epigenoma. Los grupos de plantas comparadas fueron: 1) tratadas por estrés hídrico y plantas control del cv. Tanganyika INTA y 2) plantas híbridas del primer año de análisis y luego de tres años. En el primer caso, no se hallaron cambios genéticos en el tiempo en las plantas sometidas a estrés hídrico y control, mientras que las comparaciones con marcadores MSAP permitieron evidenciar un gran número de marcadores polimórficos debidos a procesos de metilación y desmetilación del ADN entre los dos tiempos de muestreo. Si bien no existe una diferencia estadística entre la suma de cambios ocurridos en el tiempo entre el grupo de plantas control y tratadas, se observó un alto grado de correlación (R2= 0,7949) entre los porcentajes de cambios ocurridos en el tiempo y los porcentajes de sexualidad calculados a través del análisis citoembriológico para cada individuo. En el híbrido 60 no se hallaron cambios genéticos en el tiempo, pero si se hallaron en el híbrido 105. En el análisis de los perfiles epigenéticos, el híbrido 60 mostró una mayor proporción de procesos de metilación, mientras que el 105 reveló una tendencia mayoritaria hacia la desmetilación del ADN. Esto podría atribuirse a una mayor inestabilidad genómica, que podría asociarse a un comportamiento más errático del modo reproductivo. La secuenciación de una muestra de los polimorfismos obtenidos por AFLP y MSAP mostró una alta proporción (55 %) de secuencias sin homología con regiones conocidas del genoma, pudiendo tratarse de metilaciones y desmetilaciones en regiones no codificantes o en secuencias del genoma aún no informadas. Las secuencias que mostraron homología con secuencias previamente anotadas fueron principalmente elementos transponibles. Los resultados aquí presentados y los previos obtenidos por el grupo de trabajo nos permiten hipotetizar que existe una región determinante de la apomixis, que estaría ausente en las plantas tetraploides sexuales. La misma podría contener regiones repetitivas y con redundancia génica que estarían silenciando la sexualidad en plantas apomícticas. Existen numerosas evidencias sobre el control mediado por pequeños ARNs en el silenciamiento de regiones repetitivas y elementos transponibles. Ante determinadas circunstancias, como condiciones de estrés prolongado, en esta región podría estar ocurriendo un efecto de des-represión epigenética, permitiendo un aumento en la proporción de procesos sexuales. Si bien aún resta trabajo experimental para comprobar esta hipótesis, los procesos de metilación y desmetilación observados y los elementos transponibles secuenciados serían evidencias preliminares a considerar. / Stress affects the organisms generating physiological, genetic and epigenetic responses. Many authors argue that stress is a key factor to explain the evolutionary role of sex in organisms with facultative reproductive mode. Therefore, it is expected that facultative organisms will cross more frequently under stress, facilitating the adaptation to changing environments. Eragrostis curvula constitutes a polymorphic complex where most of its members reproduce by apomixis, asexual reproduction through seeds, which leads to the generation of progenies genetically identical to the mother plant. The aim of this work was to study the effect of different factors that generate genomic stress on the expression of apomixis in weeping lovegrass, such as water stress, in vitro culture, polyploidization and intraspecific hybridization. For this purpose, embryo sacs of different weeping lovegrass genotypes were observed after being the plants subjected to these stress conditions. Moreover, progeny tests were conducted by using molecular markers and the genome methylation status after different treatments was also assessed. Before evaluating the effect of the mentioned stressors on the reproductive mode it was necessary to analyze the stability of the trait throughout the flowering period, finding that plants of the cv. Tanganyika INTA growing in the greenhouse exhibited an average of sexuality less than 2 %. Plants of this cultivar subjected to water stress showed an average of 14% of sexual embryo sacs, indicating an increased expression of sexuality compared to control plants. After a rehydration period these plants showed an average of sexuality of 5.3 %, indicating a significant reduction in the number of sexual embryo sacs, being, however, significantly different from control plants. Progeny tests were performed with RAPDs markers detecting polymorphisms only in plants subjected to water stress, although in a less ratio than the expected according to the cyto-embryological analysis, indicating that not all the sexual embryo sacs produced develop into viable plants. Plants of the cv. Tanganyika USDA did not show at any time the ability to generate sexual embryo sacs and being classified as full apomictic one. The facultative genotype UNST1131 showed an expression of sexual processes of 18.5 % under water stress conditions, however this value was not significantly different to the control (10%), mainly due to the large variability exhibited by this material. To assess effects mediated by ABA, foliar application were performed on normally watered cv. Tanganyika INTA plants. The cyto-embryologic analysis was unable to detect significant differences in the number of sexual embryo sacs compared to the control, dismissing for the moment the hormone concentration as a mediator of the effect generated by stress. The effect of in vitro culture was also analyzed performing different tests in which the explant type, culture media and time under culture were changed. Tanganyika USDA and Tanganyika INTA cultivars were evaluated. In only one of the trials (exposure to selective media) a significant effect on the number of sexual embryo sacs was observed, which increased, showing a certain plasticity of the trait when the plants were growing under stress conditions. These results indicate that stress situations before and during the flowering stage might be regulating the expression of sexuality in facultative apomictic genotypes of weeping lovegrass. It is evident that Tanganyika USDA, Tanganyika INTA and UNS1131 cultivars express different levels of apomixis/sexuality ratios, from zero to 33%. This study also demonstrated that not only external conditions promote genomic stresses that alter the expression of apomixis in weeping lovegrass. Conditions such as intraspecific hybridization and polyploidization also affect the reproductive mode. The analysis of the expression of apomixis over time in two hybrids (#105 and #60) obtained from crosses between sexual X apomictic materials showed differences in the expression of the trait. The first one (#105) showed an erratic behavior in the ratio of apomictic/sexual processes, ending after two years with a ratio of 1/1, while the other (#60), only showed sexual embryo sacs on the two first blooms and a small proportion of apomictic embryo sacs during the third one. The results of progeny tests correlated very well with the cytoembryological observations. Given the close relationship between apomixis and environment, it might be speculated that the genes involved in the control of the reproductive mode could be subjected to epigenetic regulation, involving DNA methylation in some way. Comparative analyses at genomic (AFLP) and epigenetic (MSAP) levels were performed on different groups of plants in order to analyze the effect of genomic stresses. The groups compared were: 1) plants under water stress and normally watered plants (control) belonging to cv. Tanganyika INTA; 2) recently hybridized plants (first blooming) and the same plants in the third blooming period. In the first case (water stressed vs. control plants), no genetic changes over time were observed while comparisons with MSAP showed a large number of polymorphic markers due to processes of DNA methylations and de-methylations, showing a high correlation level (R2 = 0.7949) between the percentages of changes over time and the number of sexual embryo sacs. In the hybrid #60 no genetic changes were detected as it was in the #105. However, the analysis of epigenetics profiles showed a higher proportion of methylation processes in the hybrid #60 than in #105, while DNA demethylation levels were in the opposite direction. This could be associated with a higher genomic instability in #105 than in #60 that could be correlated with an increased erratic behavior of the reproductive mode. The sequencing of a sample of the polymorphic AFLP and MSAP bands showed a high proportion (55 %) of sequences without homology to previously annotated sequences, being probably noncoding regions or unknown genes. The other sequences were mainly transposable elements. The results presented here and those previously reported by our group allow us to hypothesize that there is a critical region conditioning apomixis, which would be absent in sexual tetraploid plants. This region could contain repetitive elements and gene redundancy that might be silencing sexuality in apomictic plants. Under certain circumstances, such as long stress periods, the control could be relaxed, allowing an increase in the proportion of sexual processes.

La apomixis es una forma de reproducción clonal, donde no ocurre ni meiosis ni fecundación para la formación de la semilla. Existe una estrecha relación entre la apomixis y el nivel de ploidía, dado que en la mayoría de las especies que presentan el carácter los genotipos diploides son sexuales y los poliploides son apomícticos y con un grado variable de sexualidad (facultativos). Aunque se sabe que el carácter es regulado por una o más regiones del genoma, se han hallado numerosas evidencias de mecanismos epigenéticos que regulan su expresión. Conocer los factores que determinan la apomixis tendría un gran impacto en la agricultura. Eragrostis curvula (“pasto llorón”) es una gramínea forrajera originaria de Sudáfrica, que incluye genotipos con diferentes niveles de ploidía (2X hasta 8X, con X = 10), que pueden ser sexuales o apomícticos (facultativos u obligados). Nuestro grupo de trabajo realizó numerosos estudios, sobre todo en el carácter apomixis, tanto a nivel de genética estructural como funcional. El objetivo de esta tesis fue contribuir a la dilucidación de las bases genéticas y epigenéticas que regulan uno de los componentes de la apomixis (apomeiosis) en E. curvula. Se desarrolló una población de mapeo segregante para el carácter apomixis a partir del cruzamiento entre dos genotipos tetraploides, uno sexual (OTA-S) y otro apomíctico facultativo (Don Walter). La genotipificación se realizó con marcadores DArT-SNP y el fenotipado mediante citoembriología y un marcador molecular dominante. El mapa de ligamiento quedó conformado por 20 grupos de ligamiento (GL), con el posicionamiento del APO locus en el GL1, donde también se ubicaron tres marcadores SNP 100 % ligados al carácter apomeiosis. La secuencia de los SNP 100 % ligados tienen homología con proteínas anotadas en bases de datos, que podrían estar relacionadas al modo reproductivo. Se realizó un análisis de sintenia entre los GLs del mapa consenso y el genoma de referencia de la especie (cv. Victoria) que permitió asociar todos los GLs a alguno de los contigs y hallar los GLs que corresponderían potencialmente a cada uno de los genomas del alotetraploide (homeólogos). Para la validación de los marcadores se diseñaron y evaluaron cinco primers KASP que permitieron discriminar entre los alelos de los individuos sexuales y apomícticos. En el segundo capítulo se analizaron diferentes resultados obtenidos por el grupo de trabajo que evidencian la influencia de la epigenética sobre el carácter apomixis en plantas de E. curvula. Para analizar la participación de mecanismos de metilación del ADN en la regulación de la apomixis bajo condiciones de estrés hídrico, se realizó un ensayo en el cual muestras de ADN de inflorescencias fueron evaluadas mediante la “Estimación del contenido de metilación por doble corte con enzimas de restricción sensibles” (MCSeEd). En las regiones diferencialmente metiladas se lograron encontrar genes vinculados al modo reproductivo, como BABYBOOM, ubiquitinas, FBox y subtilisinas. Podría afirmarse que tanto el estrés interno como externo ejerce una gran influencia sobre el modo reproductivo de E. curvula, modificando la expresión del carácter apomixis en plantas apomícticas facultativas. / Apomixis is a type of clonal reproduction, where neither meiosis nor fertilization occurs in seed formation. There is a close relationship between apomixis and ploidy level, since in most of the apomictic species diploid genotypes are sexuals and polyploids are apomictics. Usually, apomictic plants are facultative, being some of the seeds sexuals in origin. Although it is known that this trait is regulated by one or more genomic regions, numerous evidences of epigenetic mechanisms that regulate its expression have been found. Knowing the factors that determine apomixis could have a great impact on agriculture. Eragrostis curvula, commonly known as weeping lovegrass, is a forage grass native to southern Africa, which includes genotypes with different ploidy levels (from 2X to 8X, with X = 10) and that can be sexuals or apomictics (facultative or obligate). Our work group carried out several studies on this model species, especially related with the apomixis character, both at the structural and functional genetic level. The objective of this thesis was to contribute to the elucidation of the genetic and epigenetic bases that regulate one of the components of apomixis (apomeiosis) in E. curvula. A segregating mapping population was generated for the apomixis trait from the cross between two tetraploid genotypes, one sexual (OTA-S) and the other one facultative apomictic (Don Walter). Genotyping was performed with DArT-SNP markers and phenotyping using cytoembryological techniques and a dominant molecular marker. The linkage map was made up of 20 linkage groups (LGs), with the apomeisis locus (APO locus) located on GL1, where three SNP markers 100 % linked to the APO locus were also located. All of this 100 % linked SNPs have homology with proteins, two of these annotated in databases. A synteny analysis was performed between the GLs of the consensus map and the E. curvula reference genome (cv. Victoria), which allowed all the GLs to be associated to any of the contigs and to find the GLs that would potentially correspond to each allotetraploid genome (homeologs). For the validation of the markers, five KASP primers were design and performed, allowing to discriminate between the sexual or apomictic alleles of the ndividuals of the mapping population. Furthermore, in a second chapter, several results obtained by the work group were evaluated, demonstrating an influence of epigenetic regulation on the apomixis trait in E. curvula. To analyze the involvement of DNA methylation mechanisms in the regulation of apomixis under water stress conditions, DNA samples of inflorescences under different stress conditions were evaluated, using the “Methylation content sensitive enzime double-digest restriction-site-associated DNA” (MCSeEd) method. Some of the genes identified in the differentially methylated regions were found to be related to the reproductive mode, such as BABYBOOM, ubiquitin, F-box and subtilisin genes. It could be proposed that stress, both internal and external, has a significant influence in the reproductive mode of E. curvula, modifying the expression of the trait in facultative apomicts.

E. curvula (Schrad.) Nees “pasto llorón”, es una gramínea perenne que constituye un importante recurso forrajero para regiones semiáridas. El objetivo general de este trabajo de tesis fue contribuir al mejoramiento del pasto llorón a partir de dos estrategias. La primera consistió en la obtención de nuevos materiales híbridos a partir de cruzamientos entre materiales sexuales y apomícticos y evaluar sus características moleculares y agronómicas. Por otro lado, se intentó poner a punto un protocolo de transformación genética, basado en Agrobacterium tumefaciens, que permita contribuir al mejoramiento de la calidad del forraje por regulación negativa de la biosíntesis de lignina y que sea una herramienta para la validación de genes relacionados con el modo reproductivo. En este trabajo se realizaron 15 cruzamientos entre OTA-S USDA y Tanganyika USDA, ambos tetraploides, siendo el primero sexual y el segundo apomíctico. De estas cruzas se obtuvo un total de 2063 semillas de las cuales solo germinó el 39,31% y de este, solo se obtuvo un 15,85% de plantas normales. Se extrajo ADN de las plantas normales a fin de proceder a determinar la naturaleza híbrida de las mismas. Se utilizaron AFLPs y EST-SSR. Se obtuvieron 691 marcadores de AFLP de los cuales 317 fueron polimórficos. Con estos análisis se determinó que de las 232 plantas analizadas, solo seis resultaron de origen híbrido, es decir que portaban bandas paternas. El resto de las plantas obtenidas provenían de autofecundación del progenitor femenino OTA USDA por efecto mentor del polen del material apomíctico. Esto fue un resultado inesperado, dada la autoincompatibilidad de este genotipo. El segundo análisis con marcadores moleculares, fue realizado con el objetivo de buscar variabilidad dentro del complejo de plantas no hibridas obtenidas. En este caso se analizaron seis combinaciones de primers de marcadores de AFLPs, con los cuales se obtuvieron 376 marcadores en total, de los cuales 46 resultaron ser polimórficos. Se observó variabilidad a nivel molecular y en caracteres morfológicos y agronómicos; el progenitor masculino se diferenció a ambos niveles de las demás plantas; las plantas hijas fueron más similares a la madre aunque algunas la superaron en caracteres de interés. La distancia genética observada entre el progenitor femenino y el masculino pudo haber afectado la obtención de plantas híbridas. El bajo porcentaje de germinación (39%) observado y la elevada mortalidad de plántulas, podría también atribuirse a este factor, correspondiendo las semillas no germinadas y las plantas anómalas a híbridos no viables. Por último, se realizaron 23 ensayos para la transformación de pasto llorón utilizando dos cepas de Agrobacterium tumefaciens que difieren en su capacidad de virulencia, AGL0 y AGL1, ambas conteniendo el vector binario (Ppzp201BUGI). Se inoculó un total de 8428 semillas maduras bajo diferentes condiciones experimentales. Se obtuvo un protocolo de transformación transiente para pasto llorón a partir de semillas maduras. Deberán ajustarse algunas variables a fin de obtener un protocolo de transformación estable. / E. curvula (Schrad.) Nees "weeping lovegrass", is a perennial grass that is an important forage resource for semiarid regions. The overall objective of this thesis was to contribute to the improvement of weeping lovegrass from two strategies. The first involved the development of new hybrid materials from crosses between sexual and apomictic materials and to assess its molecular and agronomic characteristics. On the other hand, we tried to develop a protocol for genetic transformation, based on Agrobacterium tumefaciens, that could contribute to improve forage quality through downregulation of lignin biosynthesis and as a tool for validation of genes related to the reproductive mode. In this work 15 crosses between OTA-S and Tanganyika, both apomictic tetraploid materials, were perform and 2063 seeds were obtained. After two months only the 39.31% of these seeds geminated and 15.85% of these seeds gave origin to viable plants. DNA of these plants was isolated in order to assess the hybrid origin of these plants and also to analyze the variability present in the obtained plant population. EST-SSR and AFLP markers were used with this purpose and 691 AFLP markers were amplified, of which 317 were polymorphic. With these markers it could be established that from 232 analyzed plants, only six were true hybrids. This would indicate that the remaining plants were obtained by self-fertilization of the female parent OTA-S. This was an unexpected result, given the self-incompatibility of this genotype. The second analysis was performed in order to assess the variability within the obtained plant population. Six AFLPs primer combinations allowed to amplify 376 markers of which 46 were polymorphic. A high level of variation was observed at molecular, morphological and agronomic traits; the male parent differed significantly from the other plants at all levels being the offspring plants very variable and similar to the maternal plant and, is some instances superior to this plant in different interesting traits. These results also allowed to assess that the genetic distance between the female and the male parents may have affected the production of hybrid plants. The low percentage of germination (39%) and the high seedlings mortality could also be attributed to this factor.. Finally, 23 transformation assays were performed in order to establish a plant transformation protocol for weeping lovegrass using two Agrobacterium tumefaciens strains differing in its virulence (AGL1 and AGL0) and containing the binary vector Ppzp201BUGI. A total of 8428 mature seeds were inoculated and different treatments were performed changing different parameters in order to establish the best conditions for inoculation and plant regeneration. It was not possible to obtain a protocol for stable transformation but a transient transformation protocol was obtained from mature seeds. Some variables should be adjusted in order to obtain a stable and reliable transformation protocol for weeping lovegrass.

Submitted by Verena Bastos (verena@uefs.br) on 2015-08-06T14:15:43Z No. of bitstreams: 1 Disserta??o Camila Gonzaga de Jesus.pdf: 1491997 bytes, checksum: 7a4237d1223b1f93947c5ada8a9defc1 (MD5) / Made available in DSpace on 2015-08-06T14:15:43Z (GMT). No. of bitstreams: 1 Disserta??o Camila Gonzaga de Jesus.pdf: 1491997 bytes, checksum: 7a4237d1223b1f93947c5ada8a9defc1 (MD5) Previous issue date: 2013-04-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aimed to characterize the structure of plant communities, the impact caused by human action in these species and identify areas in which the fund pasture medicinal plants used by the people, through forms previously prepared and subsequent collection of plants cited in two Communities Fundo de Pasto in Village of S?o Bento and Patamut?, Cura??-Bahia. To phytosociological analysis method was used to point quadrant in 10 transects of 200 m with points spaced 20 to 20 m. We sampled all individuals shrubs and trees that had greater than 1.30 m height and diameter at ground height greater than or equal to 0.3 cm. The analysis was performed using the program Fitpoac1. We carried out a comparative analysis of floristic similarity and evaluation of the diameter distribution was calculated where the quotient ?q? to verify that the study area is balanced. The interviews were conducted in a semi-structured, for location and collection of plants was performed non-probability sampling intentional, which can be used to describe phenomena, data and generate hypotheses, using the technique ?snowball?. The analysis revealed a set phytosociological floristic represented by 11 families, 24 genera and 28 species. In S?o BentoSt. Benedict (SB) were recorded 07 families and 16 species. In Patamut? (PT) enrolled 10 families and 22 species. The Shannon diversity index was 1.62 and 2.1 in SB PT. The most abundant species common to both fragments of study is Poincianella laxiflora (Tul.) L. P. Queiroz. Cluster analysis showed that the factor of geographical proximity and human action defined the separation of the three groups formed the similarity dendrogram. For the identification of the species as medicinal interviewed 25 people, 14 men and 11 women. The Community of S?o Bento were interviewed 12 people, aged between 30 and 87 years, with 50% of respondents had more than 60 years, the Community of Patamut? 13 people were interviewed between 35 and 96 years. Informants identified uses for 38 species and 25 SB in PT, belonging to 15 plant families. The maximum use values obtained were 1.33 and 0.77 Myracrodruon. urundeuva Allem?o (aroeira) in SB, Libidibia ferrea (Mart. Ex Tul.) LP Queiroz (pau-ferro) in PT. Both species have medicinal use for inflammatory conditions. The use value average 0.38 and 0.23 in Sb and PT respectively. Regarding the frequency of citation of the use of the species in the SB Aroeira was the species most frequently mentioned by informants. In PT the ironwood was the most cited (13%). Regarding the various uses mentioned by informants communities study, treatments of conditions such as abdominal pain, flu, inflammation, kidney pain and healing were the most frequent. The study area has not provided a reason absolutely balanced, having mortality rates and growth variables, confirming the result of the strong anthropic generated by communities of bottom grazing. The results demonstrate that traditional knowledge of communities of bottom grazing areas studied might contribute significantly to the bioprospecting research to be conducted with plants of the caatinga serving as the basis for future pharmacological research and that species of lesser importance value, (Spondias tuberosa Arruda, Anadenanthera colubrina (Vell.) Brenan, Ziziphus joazeiro Mart., Myracrodruon urundeuva, Schinopsis brasiliensis Engl., Commiphora leptophloeos (Mart.) J.B.Gillett, Pseudobombax simplicifolium A. Robyns, Aspidosperma pyrifolium Mart., Jatropha multabilis (Pohl) Baill., Melochia tomentosa L., Sideroxylon obtusifolium (Roem. & Schult) e Mimosa tenuiflora (Willd.) Poir.) should be used for seedling production and recovery of bottom grazing areas studied. / O presente trabalho objetivou caracterizar a estrutura das comunidades vegetais, avaliando o impacto causado pela a??o antr?pica sob essas esp?cies identificando em ?reas de fundo de pasto quais as plantas medicinais utilizadas pela popula??o em duas Comunidades de Fundo de Pasto no Povoado de S?o Bento e Patamut?, Cura??-Bahia. Para an?lise fitossociol?gica foi utilizado o m?todo do ponto quadrante em 10 transectos de 200 m com pontos espa?ados de 20 em 20 m. Foram amostrados todos os indiv?duos arbustivos e arb?reos que apresentaram altura superior a 1,30m e di?metro ? altura do solo maior ou igual a 0,3cm. A an?lise foi realizada atrav?s do programa Fitopac1. Realizou-se a an?lise comparativa por similaridade flor?stica e a avalia??o da distribui??o diam?trica onde se calculou o quociente ?q?, para verificar se a ?rea de estudo estava balanceada. As entrevistas foram realizadas de forma semiestruturadas. Para localiza??o e coleta das plantas foi realizada a amostragem intencional n?o-probabil?stica, com uso da t?cnica ?bola de neve?. A an?lise fitossociol?gica revelou um conjunto flor?stico representado por 11 fam?lias, 24 g?neros e 28 esp?cies. Em S?o Bento (SB) foram registradas 07 fam?lias e 16 esp?cies. Em Patamut? (PT) registrou-se 10 fam?lias e 22 esp?cies. O ?ndice de diversidade de Shannon foi de 1,62 nats/ind em SB e 2,1 nats/ind em PT. A esp?cie mais abundante comum aos dois fragmentos de estudo ? Poincianella laxiflora (Tul.) L. P. Queiroz (catingueira). A an?lise de agrupamento mostrou que o fator proximidade geogr?fica e a??o antr?pica definiu a separa??o dos tr?s grupos formados no dendrograma de similaridade. Para a identifica??o das esp?cies como medicinais foram entrevistadas 25 pessoas, sendo14 homens e 11 mulheres. Na Comunidade de S?o Bento foram entrevistadas 12 pessoas com idade entre 30 e 87 anos, sendo que 50% dos entrevistados possu?am mais de 60 anos, na Comunidade de Patamut? foram entrevistadas 13 pessoas entre 35 e 96 anos. Os informantes identificaram usos para 38 esp?cies em SB e 25 em PT, pertencentes a 15 fam?lias bot?nicas. Os valores de uso m?ximos para a Myracrodruon urundeuva Allem?o (aroeira) em SB foi 1,33 e para a Libidibia ferrea (Mart. Ex Tul.) L.P. Queiroz (pau-ferro) em PT foi de 0,77. Ambas as esp?cies possui utiliza??o medicinal para problemas inflamat?rios. O valor de uso m?dio 0,38 e 0,23 em Sb e PT respectivamente. Em rela??o ? frequ?ncia de cita??o do uso das esp?cies, em SB a aroeira foi a esp?cie mais citada pelos informantes (9%). Em PT o pau-ferro foi o mais citado (13%). Em rela??o aos diversos usos citados pelos informantes das comunidades de estudo, os tratamentos de afec??es como dor de barriga, gripe, inflama??o, dor nos rins e cicatrizante foram os mais frequentes. A ?rea estudada n?o apresentou uma raz?o absolutamente balanceada, possuindo taxas de mortalidade e crescimento vari?veis, comprovando a forte conseq??ncia da a??o antr?pica gerada pelas comunidades de fundo de pasto. Os resultados demonstraram que o conhecimento tradicional das comunidades de ?reas de fundo de pasto estudadas pode vir a contribuir com as pesquisas de bioprospec??o a serem realizadas com plantas da caatinga servindo de base para futuras pesquisas farmacol?gicas e que as esp?cies de menor valor de import?ncia (Spondias tuberosa Arruda, Anadenanthera colubrina (Vell.) Brenan, Ziziphus joazeiro Mart., Myracrodruon urundeuva, Schinopsis brasiliensis Engl., Commiphora leptophloeos (Mart.) J.B.Gillett, Pseudobombax simplicifolium A. Robyns, Aspidosperma pyrifolium Mart., Jatropha multabilis (Pohl) Baill., Melochia tomentosa L., Sideroxylon obtusifolium (Roem. & Schult) e Mimosa tenuiflora (Willd.) Poir.) devem ser utilizadas para produ??o de mudas e recupera??o das ?reas de fundo de pasto estudadas.

GONÇALVES, Josemir de Souza. Composição química e fracionamento dos carboidratos da biomassa de panicum maximum cv. Tanzânia sob três períodos de descanso. 2006. 82 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Fortaleza-CE, 2006 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-01T14:52:50Z No. of bitstreams: 1 2006_dis_jsgoncalves.pdf: 500928 bytes, checksum: dfb947038c644cea8d4a1a6e84dfd74a (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-01T14:53:17Z (GMT) No. of bitstreams: 1 2006_dis_jsgoncalves.pdf: 500928 bytes, checksum: dfb947038c644cea8d4a1a6e84dfd74a (MD5) / Made available in DSpace on 2016-08-01T14:53:17Z (GMT). No. of bitstreams: 1 2006_dis_jsgoncalves.pdf: 500928 bytes, checksum: dfb947038c644cea8d4a1a6e84dfd74a (MD5) Previous issue date: 2006 / The experiment was carried out in the advanced field of the Forage Research Sector - NPF (www.npf.ufc.br) located in the Experimental Farm of the Vale do Curu - FEVC, belonging to Federal University of Ceará - UFC. The objective was evaluate the chemical composition and the carbohydrate fractionation of Panicum maximum cv. Tanzânia biomass under three rest periods (RPs) based in the new leaf (L) number expanded for tiller (1.5; 2.5 and 3.5L). Was used the completely randomized design in a factorial arrangement 3x3 (3 fractions and 3 RPs). The harvest of the samples was made before the entrance and after the exit the animals the poles. Later, the samples had been separate in the fractions leaf, culm and death material, being droughts in greenhouse of forced ventilation 65° C for 72 hours, and processed. In the Laboratory of Animal Nutrition of the Animal Science Department of UFC (LNA/DZ/UFC), were determined the levels of Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Hemi-cellulose (HC), Cellulose (CEL), Lignin (LIG), Etereal Extract (EE), Crude Protein (PB), Insoluble Nitrogen in Neutral Detergent (INND), Insoluble Nitrogen in Acid Detergent (INAD), Total Total Carbohydrates (TC), Non Fiber Carbohydrates (NFC), and of the fractions that compose the TC: A+B1, B2 and C. The levels of NDF and ADF had been raised (P<0.05) with the advance of the RPs. The entire plant (EP) of the grass under bigger RP (3.5L), in the before grazing, presented levels, respectively, of 74.0 and 46.3% being these raising for 77,3 and 50,9% after grazing. The levels of LIG of leaf fraction of the grass under RP 3.5L (4.2%) had suffered rises (P<0.05) after grazing. The LIG levels in the RP were higher (P<0.05) in those submitted to 3.5L RP in comparison to the EPs of the 1.5L RP in such a way in before grazing (4.7 and 5.3%) how much after grazing (4.7 and 5.3%). The biggest levels of PB of the leaf fraction had been found in the grass under 1.5L RP (10,86 and 8.59%), before grazing and after grazing. The levels of CP in the entire plant had varied of 8.8 6.4% (P<0.05) and 6.16 and 4.4% (P<0.05) between 3.5 and 1.5L RPs, respectively before and after grazing. The INAD levels, had been also raised (P<0.05) in the EP of 3.5L RP (20.3 and 28.5%), respectively before and after grazing. The levels of TC of the leaf fraction and the EP had presented average levels (P>0.05) of 75.4 and 77.4% before grazing and 79.2 and 89.2% after grazing. The C carbohydrates fraction presented average between 11.4 11.9%, in the leaf fraction, whereas in the EP of the grass under 3.5L RP, had been observed biggest levels (P<0.05) of this fraction (14.3 and 15.7), in both cases when observed before grazing and pos-grazing. The Tanzânia grass under 1.5L RP presented the best chemical composition of that they had been evaluated. However, it is necessary that information on the chemical composition of the grass are taken in consideration in set with the occured changes in the structure of the grass so that if can have a bigger exactness in the evaluation of the quality of the grass. / O experimento foi conduzido no campo avançado do Núcleo de Pesquisa em Forragicultura - NPF (www.npf.ufc.br) localizado na Fazenda Experimental do Vale do Curu – FEVC, pertencente à Universidade Federal do Ceará – UFC. Objetivou-se avaliar a composição química e o fracionamento dos carboidratos da biomassa de Panicum maximum cv. Tanzânia sob três períodos de descanso (PDs) baseados no número de novas folhas expandidas por perfilho (1,5; 2,5 e 3,5F). Utilizou-se o delineamento inteiramente casualizado em arranjo fatorial 3x3 (3 frações e 3 PDs). A colheita das amostras foi feita antes da entrada e após a saída dos animais dos piquetes. Posteriormente, as amostras foram separadas nas frações folha, colmo e material morto. No Laboratório de Nutrição Animal do Departamento de Zootecnia da UFC (LNA/DZ/UFC), foram determinados os teores de Fibra em Detergente Neutro (FDN), Fibra em Detergente Ácido (FDA), Hemicelulose (HEM), Celulose (CEL), Lignina (LIG), Extrato Etéreo (EE), Proteína Bruta (PB), Nitrogênio Insolúvel em Detergente Neutro (NIDN), Nitrogênio Insolúvel em Detergente Ácido (NIDA), Carboidratos Totais (CT), Carboidratos Não Fibrosos (CNF), e das frações que compõem os CT: A+B1, B2 e C. Os teores de FDN e de FDA foram elevados (P<0,05) com o avanço dos PDs. A planta inteira (PI) do pasto sob maior PD (3,5F), no pré-pastejo, apresentou teores, respectivamente, de 74,0 e 46,3% sendo estes elevados para 77,3 e 50,9% no pós pastejo. Os teores de LIG da fração folha do pasto sob PD 3,5F (4,2%) sofreram elevações (P<0,05) no pré-pastejo. Os teores de LIG na PI foram superiores (P<0,05) naquelas submetidas ao PD 3,5F em comparação às PIs do PD 1,5F tanto no pré-pastejo (4,7 e 5,3%) quanto no pós-pastejo (4,7 e 5,3%). Os maiores teores de PB da fração folha foram encontrados nos pastos sob PD 1,5F (10,9 e 8,6%), no pré e pós-pastejo. Os teores de PB na planta inteira variaram de 8,8 a 6,4% (P<0,05) e 6,2 e 4,4% (P<0,05) entre os PDs 1,5 e 3,5F, respectivamente no pré e pós-pastejo. Os teores de NIDA, também foram elevados (P<0,05) na PI do PD 3,5F (20,3 e 28,5%), respectivamente no pré e pós-pastejo. Os teores de CT da fração folha e da PI apresentaram teores médios (P>0,05) de 75,4 e 77,4% no pré-pastejo e 79,2 e 89,2% no pós pastejo. A fração C dos carboidratos apresentou variação média de 11,4 a 11,9%, na fração folha, enquanto que na PI do pasto sob PD 3,5 F, foram observados os maiores teores (P<0,05) desta fração (14,4 e 15,7%), em ambos os casos quando observados no pré e pós-pastejo. O pasto de capim Tanzânia manejado sob PD 1,5F apresentou a melhor composição química dos que foram avaliados. Contudo é necessário que informações sobre a composição química dos pastos sejam levadas em consideração em conjunto com as mudanças ocorridas na estrutura do pasto para que se possa ter uma maior exatidão na avaliação da qualidade dos pastos.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O experimento foi conduzido no campo avanÃado do NÃcleo de Pesquisa em Forragicultura - NPF (www.npf.ufc.br) localizado na Fazenda Experimental do Vale do Curu â FEVC, pertencente à Universidade Federal do Cearà â UFC. Objetivou-se avaliar a composiÃÃo quÃmica e o fracionamento dos carboidratos da biomassa de Panicum maximum cv. TanzÃnia sob trÃs perÃodos de descanso (PDs) baseados no nÃmero de novas folhas expandidas por perfilho (1,5; 2,5 e 3,5F). Utilizou-se o delineamento inteiramente casualizado em arranjo fatorial 3x3 (3 fraÃÃes e 3 PDs). A colheita das amostras foi feita antes da entrada e apÃs a saÃda dos animais dos piquetes. Posteriormente, as amostras foram separadas nas fraÃÃes folha, colmo e material morto. No LaboratÃrio de NutriÃÃo Animal do Departamento de Zootecnia da UFC (LNA/DZ/UFC), foram determinados os teores de Fibra em Detergente Neutro (FDN), Fibra em Detergente Ãcido (FDA), Hemicelulose (HEM), Celulose (CEL), Lignina (LIG), Extrato EtÃreo (EE), ProteÃna Bruta (PB), NitrogÃnio InsolÃvel em Detergente Neutro (NIDN), NitrogÃnio InsolÃvel em Detergente Ãcido (NIDA), Carboidratos Totais (CT), Carboidratos NÃo Fibrosos (CNF), e das fraÃÃes que compÃem os CT: A+B1, B2 e C. Os teores de FDN e de FDA foram elevados (P<0,05) com o avanÃo dos PDs. A planta inteira (PI) do pasto sob maior PD (3,5F), no prÃ-pastejo, apresentou teores, respectivamente, de 74,0 e 46,3% sendo estes elevados para 77,3 e 50,9% no pÃs pastejo. Os teores de LIG da fraÃÃo folha do pasto sob PD 3,5F (4,2%) sofreram elevaÃÃes (P<0,05) no prÃ-pastejo. Os teores de LIG na PI foram superiores (P<0,05) naquelas submetidas ao PD 3,5F em comparaÃÃo Ãs PIs do PD 1,5F tanto no prÃ-pastejo (4,7 e 5,3%) quanto no pÃs-pastejo (4,7 e 5,3%). Os maiores teores de PB da fraÃÃo folha foram encontrados nos pastos sob PD 1,5F (10,9 e 8,6%), no prà e pÃs-pastejo. Os teores de PB na planta inteira variaram de 8,8 a 6,4% (P<0,05) e 6,2 e 4,4% (P<0,05) entre os PDs 1,5 e 3,5F, respectivamente no prà e pÃs-pastejo. Os teores de NIDA, tambÃm foram elevados (P<0,05) na PI do PD 3,5F (20,3 e 28,5%), respectivamente no prà e pÃs-pastejo. Os teores de CT da fraÃÃo folha e da PI apresentaram teores mÃdios (P>0,05) de 75,4 e 77,4% no prÃ-pastejo e 79,2 e 89,2% no pÃs pastejo. A fraÃÃo C dos carboidratos apresentou variaÃÃo mÃdia de 11,4 a 11,9%, na fraÃÃo folha, enquanto que na PI do pasto sob PD 3,5 F, foram observados os maiores teores (P<0,05) desta fraÃÃo (14,4 e 15,7%), em ambos os casos quando observados no prà e pÃs-pastejo. O pasto de capim TanzÃnia manejado sob PD 1,5F apresentou a melhor composiÃÃo quÃmica dos que foram avaliados. Contudo à necessÃrio que informaÃÃes sobre a composiÃÃo quÃmica dos pastos sejam levadas em consideraÃÃo em conjunto com as mudanÃas ocorridas na estrutura do pasto para que se possa ter uma maior exatidÃo na avaliaÃÃo da qualidade dos pastos. / The experiment was carried out in the advanced field of the Forage Research Sector - NPF (www.npf.ufc.br) located in the Experimental Farm of the Vale do Curu - FEVC, belonging to Federal University of Cearà - UFC. The objective was evaluate the chemical composition and the carbohydrate fractionation of Panicum maximum cv. TanzÃnia biomass under three rest periods (RPs) based in the new leaf (L) number expanded for tiller (1.5; 2.5 and 3.5L). Was used the completely randomized design in a factorial arrangement 3x3 (3 fractions and 3 RPs). The harvest of the samples was made before the entrance and after the exit the animals the poles. Later, the samples had been separate in the fractions leaf, culm and death material, being droughts in greenhouse of forced ventilation 65 C for 72 hours, and processed. In the Laboratory of Animal Nutrition of the Animal Science Department of UFC (LNA/DZ/UFC), were determined the levels of Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Hemi-cellulose (HC), Cellulose (CEL), Lignin (LIG), Etereal Extract (EE), Crude Protein (PB), Insoluble Nitrogen in Neutral Detergent (INND), Insoluble Nitrogen in Acid Detergent (INAD), Total Total Carbohydrates (TC), Non Fiber Carbohydrates (NFC), and of the fractions that compose the TC: A+B1, B2 and C. The levels of NDF and ADF had been raised (P<0.05) with the advance of the RPs. The entire plant (EP) of the grass under bigger RP (3.5L), in the before grazing, presented levels, respectively, of 74.0 and 46.3% being these raising for 77,3 and 50,9% after grazing. The levels of LIG of leaf fraction of the grass under RP 3.5L (4.2%) had suffered rises (P<0.05) after grazing. The LIG levels in the RP were higher (P<0.05) in those submitted to 3.5L RP in comparison to the EPs of the 1.5L RP in such a way in before grazing (4.7 and 5.3%) how much after grazing (4.7 and 5.3%). The biggest levels of PB of the leaf fraction had been found in the grass under 1.5L RP (10,86 and 8.59%), before grazing and after grazing. The levels of CP in the entire plant had varied of 8.8 6.4% (P<0.05) and 6.16 and 4.4% (P<0.05) between 3.5 and 1.5L RPs, respectively before and after grazing. The INAD levels, had been also raised (P<0.05) in the EP of 3.5L RP (20.3 and 28.5%), respectively before and after grazing. The levels of TC of the leaf fraction and the EP had presented average levels (P>0.05) of 75.4 and 77.4% before grazing and 79.2 and 89.2% after grazing. The C carbohydrates fraction presented average between 11.4 11.9%, in the leaf fraction, whereas in the EP of the grass under 3.5L RP, had been observed biggest levels (P<0.05) of this fraction (14.3 and 15.7), in both cases when observed before grazing and pos-grazing. The TanzÃnia grass under 1.5L RP presented the best chemical composition of that they had been evaluated. However, it is necessary that information on the chemical composition of the grass are taken in consideration in set with the occured changes in the structure of the grass so that if can have a bigger exactness in the evaluation of the quality of the grass.