Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-19Bitstream added on 2014-06-13T20:40:15Z : No. of bitstreams: 1 miranda_ac_me_botfca.pdf: 352756 bytes, checksum: e94f547138bf0223054b6f08ecb6ee76 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O Eucalyptus grandis é uma das espécies mais plantadas no Brasil devido às características silviculturais e a sua adaptação a diferentes condições edafoclimáticas, o que possibilita resultados significativos de rendimento volumétrico. Diversas procedências e progênies vêm sendo estudadas com o propósito de se conhecer a estrutura genética destas populações, o que facilitará a obtenção de material genético adequado ao desenvolvimento de programas de melhoramento florestal no país. O objetivo deste trabalho foi realizar o zoneamento ecológico por meio da análise de estabilidade, adaptabilidade e produtividade de progênies de Eucalyptus grandis, utilizando-se do método MHPRVG (média harmônica da performance relativa dos valores genéticos) preditos por BLUP e estimar a variabilidade genética a partir de caracteres quantitativos. Foram instalados quatro testes de progênies de polinização aberta nos municípios de Anhembi, Avaré, Itararé e Pratânia. O delineamento experimental utilizado foi o de blocos casualizados, com quatro e seis repetições e seis plantas por parcela. Um total de 153 a 160 tratamentos (progênies) foram avaliados para diâmetro a altura do peito, altura das árvores e volume, nos quatro ensaios as medições foram realizadas aos 12 e 24 meses de idade. Os parâmetros genéticos, para o estudo de estabilidade, adaptabilidade e produtividade dos genótipos de E. grandis, foram estimados por meio da metodologia REML/BLUP. Os altos valores encontrados para o coeficiente de variação genética demostram que existe alta variabilidade genética entre as progênies, corroboradas com altas herdabilidades médias, os efeitos da interação genótipos ambientes foram significativos. O método da MHPRVG permitiu a seleção de progênies com alto potencial produtivo predito, classificadas simultaneamente... / The Eucalyptus grandis is a species grown in Brazil due to forest features and their adaptation to different climatic conditions, which enables significant results of volumetric efficiency. Several provenances and progenies have been studied in order to understand the genetic structure of these populations, which will facilitate the acquisition of genetic material suitable for development of forest breeding programs in the country. The objective of this study was realize the ecological zoning through the analysis of stability, adaptability and productivity of progenies of Eucalyptus grandis, using the method MHPRVG (harmonic mean of the relative performance of the predicted genetic values) predicted by BLUP and estimate the genetic variability from quantitative traits. Were installed four sites of Open-pollinated progenies in the municipalities of Anhembi, Avaré, Itararé and Pratânia. Were established in a randomized complete blocks design with the families at each site numbering from 153 to 160, the blocks at each site numbering from four to six and the trees per plot ranging from to six, were evaluated for trees diameter at breast height, height and volume, at four sites measurements were at 12 and 24 months. The genetics parameters for study of stability, adaptability and productivity of genotype of E. grandis, were estimate by genetic REML/BLUP. The high values found for coefficient of genetic variation showing high genetic variability among progenies, corroborated with high heritability means, the effects of genotype x environments were significant. The method of MHPRVG allowed the selection of progenies with high yield potential predicted, classified simultaneous by productivity, stability and adaptability. The high values of heritability means of progenies above 67% progeny allow anticipating the successful selection of... (Complete abstract click electronic access below)

Thesis (M.S.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 35-41). Also available on the World Wide Web.

Orientador: Giuseppina Pace Pereira Lima / Coorientador: Elizabeth Orika Ono / Banca: Luciana Francisco Freire / Banca: Armando Reis Tavares / Resumo: A propagação vegetativa é a principal forma de produção de mudas de Eucalyptus, porém alguns materiais clonais ainda apresentam dificuldades de propagação, inclusive no enraizamento. Indiretamente, os flavonóides e o peróxido de hidrogênio podem favorecer este processo, assim como alterar os níveis de substâncias antioxidantes, como enzimas e compostos fenólicos. O objetivo deste trabalho foi avaliar a ação do flavonóide quercetina, peróxido de hidrogênio e ácido indol butírico (IBA) no enraizamento e desenvolvimento de Eucalyptus grandis x urophylla, bem como nos mecanismos de produção de antioxidantes e proteção das células contra danos oxidativos. O estudo foi dividido em duas fases. Inicialmente os clones foram submetidos a tratamentos com combinação de peróxido de hidrogênio (0; 1,75; 3,5 e 7,0%) e IBA (0; 1.000 mg kg-1) e a combinação de quercetina (0; 250; 500; 1.000 mg kg-1) e IBA (0; 1.000 mg kg-1). Os tratamentos foram aplicados em estacas e as mudas foram avaliadas em relação aos trinta, sessenta e noventa dias após o plantio em relação a altura, diâmetro e porcentagem de sobrevivência. Aos noventa dias uma avaliação destrutiva foi realizada e determinados a porcentagem de enraizamento, o tamanho médio da maior raiz e a quantidade de raízes. Após esta avaliação, o peróxido de hidrogênio (0;3,5%), IBA (0; 1.000 mg kg-1) e a quercetina (0; 500 mg kg-1) foram combinados a fim de verificar a interação de peróxido de hidrogênio, quercetina e IBA sobre algumas moléculas com capacidade antioxidante. Noventa dias após o plantio, os efeitos desses compostos na atividade das enzimas IAA-oxidase, peroxidase, polifenoloxidase, fenilalanina amônio liase e poliamina oxidase e nos teores de compostos fenólicos, flavonoides, antocianinas e poliaminas foram avaliados por métodos espectofotométricos e teores de quercetina e ácido indolacético foram avaliados ... / Abstract: Vegetative propagation is the main form to produce cuttings of Eucalyptus, but some clones still have difficulties in propagation, including on rooting process. Indirectly, flavonoids and hydrogen peroxide can enhance this process, as well as modify the levels of antioxidants such as phenolic compounds and enzymes. This work was aimed to evaluate flavonoid quercetin, hydrogen peroxide and indolbutyric acid (IBA) action on rooting of cuttings of Eucalyptus grandis x urophylla, as well as in mechanisms of antioxidants production and cells protection against oxidative damage. The study was divided into two phases. Initially, clones were subjected to treatments with combination of hydrogen peroxide (0, 1.75, 3.5 and 7.0%) and IBA (0, 1.000 mg kg-1) and combination of quercetin (0, 250, 500, 1.000 mg kg-1) and IBA (0, 1.000 mg kg-1). Treatments were applied to cuttings and evaluated in thirty, sixty and ninety days after planting in relation to height, diameter and survival percentage. Ninety days after planting, a destructive evaluation was performed and percentage of rooting, average size of the largest root and the amount of roots were determined. After this evaluation, hydrogen peroxide (0, 3.5%), IBA (0, 1000 mg kg-1) and quercetin (0,500 mg kg-1) were combined in order to verify the interaction of hydrogen peroxide, quercetin and IBA on some molecules with antioxidant capacity. Ninety days after planting, these compounds effects on the activity of IAA oxidase, peroxidase, polyphenol oxidase, phenylalanine ammonia lyase and polyamine oxidase and the levels of phenolics, flavonoids, anthocyanins and polyamines were evaluated by spectrophotometric methods and levels of quercetin and indole acetic acid were evaluated via LC/MS in leaves and roots. Data were subjected to analysis of variance (ANOVA) and Tukey test at 5 % probability. No significant differences were found in relation to height, diameter, survival ... / Mestre

Eucalyptus grandis and its hybrids is the most important and widely planted eucalypt in South Africa. It has a wide range of uses including pulpwood, poles, firewood, charcoal, flooring, mining, furniture and general carpentry. Conservation of plant genetic resources including those used in agriculture, horticulture and forestry has become an issue of common global concern. Cryopreservation involves the storage of plant material at ultra low temperature (-196°C). The techniques for cryopreservation currently in use are varied and include the older classical techniques and the new vitrification-based techniques. Storage of biological material at -196°C causes metabolic functions to slow down considerably and minimize biological degradation, thus allowing for long-term preservation. However, there are particular stresses associated with the freezing process, e.g., ice crystal formation and cryo-dehydration, which may severely damage the material. Tolerance to drying is the key to successful cryopreservation and is commonly used in the preparation of in vitro material for cryostorage. However, drying may result in damages and a number of stresses that may activate caspase-like proteases and trigger cell death processes such as programmed cell death and necrosis. During the drying process, the physical and physiological characteristic of the cell changes because of the removal of water and damage is reflected by the lack of resumption of normal activity upon rehydration. As part of a cryo-procedure, Eucalyptus grandis axillary buds isolated from in vitro shoots were dried over silica gel for 20 minutes. Pre-treatment of the shoots with 5mg.l-1 ABA for 5 days resulted in partial resistance of the isolated buds to water loss (76% to 45%) as compared with untreated buds (76% to 33%). Concomitantly, viability decreased from 100 to 70% for ABA treated buds and to 55% for the untreated buds. Ultrastructural examination showed cellular responses to drying, ranging from cell death, through partial disruption to organelles to apparently normal ultrastructure. The use of the vital stains, 4,6-diamidino-2-phenylindole and propidium iodide, showed that certain regions of the buds (e.g. the leaf primordia) were the most prone to drying damage. The meristem, however, appeared to survive drying and for up to 72 hours of rehydration. High Reactive Oxygen Species (ROS) activity was associated with bud excision and the drying procedure. Caspase-3-like protease activity was detected after drying and rehydration in both nonviable treated and untreated buds, but not in the hydrated controls. The Caspase-3 inhibitors Ac-DEVD-CHO, pepstatin and leupeptin partially suppressed that activity. The ultrastructural studies and the use of the vital stains provided confirmation of the beneficial effects of ABA. The detection of a caspase-3- like protease has provided some evidence that the rehydrated buds, that had ultimately died, had undergone programmed cell death. The ROS production during bud isolation which was exacerbated by the drying procedure is considered to be the trigger for the programmed cell death. Data in the present study showed the role of both necrosis and PCD in the death of the tissues of the axillary buds of E. grandis axillary buds. The data also contributed to the better understanding of the impact of cryoprocedures on these clonal tissues which are ideal propagules for forestry germplasm conservation.

Alien invasive species can have serious negative impacts on the biodiversity and functioning of ecosystems, but identifying invaders early, before they cause problems, can dramatically reduce the costs of controlling them. There is substantial research in identifying key attributes of invasive species, which can potentially be used in this regard. Many Eucalypts have formed the backbone of forestry in South Africa since the 1800s. While many other plantation species such as pines and legumes, have become serious invaders in many parts of the world, Eucalyptus species have been not been nearly as successful in invading alien environments. This is surprising considering that in their native habitat; members of this genus dominate almost all vegetation types. This project used available theory on the qualities that characterise invasive species to assess the invasive potential of one Eucalyptus species: Eucalyptus grandis (rose gum). Many alien plants take a long time to establish naturalised populations and spread through new ecosystems and this research will provide information on the likelihood that E. grandis will become a problem species in the future. A field study was used to determine whether there is any indication that it is in fact, invading from plantations in Mpumalanga, and if so, which ecological processes affect this invasion potential. Belt transects (5 by 50 metres) were used in sampling the populations growing near plantations. To determine whether frost is affecting the populations, one site was at high elevation where it is exposed to frost (near Graskop) and the other at a low elevation area with infrequent frost (near White river). Key reproductive traits such as generation time and seed viability which are known to affect invasion potential were also studied. Demographic data was used to determine the rates of establishment of E. grandis outside of plantations. The results showed that E. grandis had a short generation time and its seeds had a viability of 97%. Assessing the shape parameter (c) of the Weibull distribution function showed that both the Graskop (c=1) and White River (c=1) size class distributions had reverse j-shaped curves, characteristic of good rejuvenation. However, some Graskop sites had a monotonic function (c < 1) showing that frost is affecting the rejuvenation process. Generally the results show that rate of spread is low and this might suggest that the populations are on the establishing populations’ invasion stage. However, there is no indication that there are any environmental or life history factors that would prevent Eucalyptus from becoming invasive in the future, and I would recommend strict monitoring of its rates of spread out of plantation forests in various parts of the country.

Os agrupamentos de ferro-enxofre (Fe-S) são grupos prostéticos necessários para a manutenção da vida, pois estão envolvidos em diversos processos incluindo a transferência de elétrons, reações metabólicas, sinalização e regulação da expressão gênica. As plantas realizam fotossíntese e respiração, dois processos que requerem proteínas Fe-S, sendo os únicos organismos em que a síntese destas proteínas é compartimentalizada. Diversos fatores afetam o desenvolvimento das plantas, entre eles, a temperatura baixa, fator limitante à produtividade e à distribuição geográfica das plantas, incluindo Eucalyptus grandis, uma espécie com grande importância econômica. Neste trabalho foi realizada uma análise transcricional dos genes NFS1, ISA1 e ISU1 de E. grandis após diferentes estúmlos por meio de PCR quantitativa (qRT-PCR) e microarranjos. Após o tratamento de plântulas de E. grandis com frio, foram realizados experimentos de qRT-PCR. Os resultados foram normalizados com os genes constitutivos codificadores da histona H2B e da ribonucleoproteína L23A. Considerando tal normalização, ISU1 aumentou sua expressão em 0,6 e 1,7 vezes, NFS1 apresentou um aumento de 6 e 8 vezes, enquanto ISA1 apresentou um aumento de 69 a 114 vezes em relação à condição controle. Utilizando-se a técnica de microarranjos, foi analisada a diferença de expressão entre folhas e xilema de árvores maduras de E. grandis. O gene NFS1 apresentou maior expressão nas folhas do que em xilema, porém os genes ISA1 e ISU1 apresentaram um padrão de expressão equivalente entre os dois tipos de tecidos. Esses resultados sugerem que (i) os genes NFS1 e ISA1 podem estar relacionados à resposta celular ao estresse causado por frio; e que (ii) os aumentos na expressão devem-se, provavelmente, ao metabolismo de enxofre e à indução de enzimas antioxidantes. Foi também realizado um experimento de curva de tempo com a submissão de plântulas de E. grandis ao resfriamento, objetivando-se verificar em que momento esses genes começam a ter suas expressões aumentadas. O gene ISU1 apresentou maior expressão gênica nas primeiras duas horas de tratamento, caindo drasticamente logo após este período. O gene ISA1, que havia apresentado a maior expressão relativa no experimento anterior, não apresentou diferença significativa no padrão de expressão durante as 16 horas de resfriamento, assim como o gene NFS1. Esses resultados indicam que as proteínas Fe-S, frente ao resfriamento, estão possivelmente envolvidas na recuperação das plantas após tal estresse. / Iron-sulfur (Fe-S) clusters are prosthetic groups required for the maintenance of life because they are involved in various vital processes, including electron transfers, metabolic reactions, signaling and regulation of gene expression. Plants perform photosynthesis and respiration, two processes that require Fe-S proteins, and are the only organisms in which the synthesis of these proteins is compartmentalized. Several factors and stresses affect the development of plants including low temperature, which is a productivity-limiting factor and restricts plants to certain geographical distributions, including Eucalyptus grandis, a species with significant economic importance. The aim of this study is to perform an analysis of E. grandis NFS1 and ISA1 gene expressions after different stimuli through quantitative PCR (qRT-PCR) and microarrays. qRT-PCR experiment were conducted on plants submitted to a cold treatment. The results were normalized with the housekeeping genes encoding histone H2B and ribonucleoprotein L23A. Considering such normalizations, ISU1 increased the expression 0.6 and 1-fold, NFS1 showed a 6 and 8-fold increase in comparison with the control condition, while ISA1 gene increased 69 and 114-fold. Using microarrays, the difference in expression between leaves and xylem of E. grandis was analyzed. The NFS1 gene showed higher expression in leaves than in xylem, but the ISA1and ISU1 showed equivalent pattern of expression in both types of tissues. These results suggest that (i) NFS1 and ISA1 genes are related to the cellular response to the stress caused by chilling, and that (ii) the increased expression should be probably due to the metabolism of sulfur and to the induction of antioxidative enzymes. A time-course experiment was also conducted during the cold stress of E. grandis plants to look at which moment these genes begin to increase their expressions. The ISU1 gene showed higher expression in the first 2 hours of treatment, and than decreased severally after this period. The ISA1 gene, which had shown the highest expression in the previous experiment, did not show significant differences in the pattern of expression during the 16 hours of chilling treatment, as well as the NFS1 gene. These results indicate that Fe-S proteins, in response to low temperature, are possibly involved in the recovery of the plants after this stress.

Hybrid clones of Eucalyptus grandis and E. nitens (GN) have consistently been shown to be suitable for planting in cold, dry, marginal plantation sites, where they exhibit high yields and superior pulp properties. However, their clonal propagation is hindered by the very poor rooting success of cuttings. The present study aimed at assessing the effect of cutting type, time of year of setting cuttings and Seradix 2 application on rooting and development of cuttings of a commercially important Eucalyptus grandis x Eucalyptus nitens clone (GN107). Cuttings were prepared from clonal hedge coppice at the Mondi Business Paper, Trahar Technology Centre, Hilton. Three cutting types were used (cut at different distances from the node) for each terminal (situated below the apical bud) and non-terminal cuttings. The leaves were trimmed and, for half the cuttings, the base of the stem of cuttings were dipped in Seradix 2 rooting powder (3 g kg-1 4-(indole-3-yl)-butyric acid (IBA). They were then placed into rooting trays (128 inserts/ tray arranged as 8 rows x 16 columns). Seradix 2-treated and Seradix 2-untreated terminal and non-terminal cuttings, cut at, above and below the node (twelve treatments in total) were set in trays with one treatment per column of eight replicates, per tray. There were nineteen trays overall. The trays were filled with peat, perlite and vermiculite (3:3:1) and were maintained in a Mondi greenhouse, with air temperature at 25°C to 27°C (thermostatically activated fans), root zone temperature at 28°C (bed heaters) and 20 second misting at 10 minute intervals (automatic misters). The study was carried out in November 2005, April 2006 and June 2006. In the first experiment, both terminal and non-terminal cuttings were used; thereafter only non-terminal cuttings were used. The plantlet yield was very low, regardless of cutting type, Seradix 2 treatment and the time of year the cuttings were set. The highest plantlet production (12.5%) and rooting frequencies (13.8%) were achieved with non-terminal cuttings treated with Seradix 2. Although not statistically significant, Seradix 2 inhibited shoot production (31.4% for Seradix 2-untreated and 24.2% for treated cuttings). The position at which inserts were cut in relation to the node did not significantly affect the number of plantlets produced and non-terminal cuttings appeared hardier and performed better than terminal cuttings. The time of year of setting cuttings did not have any significant effect on plantlet yield, nonetheless, plantlet yield was highest in cuttings set in November (9.2%) and lowest in April (0.4%). In addition, cuttings set in November (spring), had superior shoot development in terms of the number of cuttings that produced shoots (regardless of root production), shoot length and the mass of shoots relative to root mass. The highest percentages of cuttings that produced roots (regardless of shoot growth) (10%) and the highest number of roots per cutting (2) were part of the June trial. Therefore, cuttings set in June (winter) had superior root development as compared with cuttings set in November (spring) or April (autumn). In all of the studies, three rooting patterns were observed in cuttings: roots produced only from the cut area only (type 1), only from the sides of the stem (type 2) and from both sites (type 3). Non-terminal cuttings treated with Seradix 2 showed a higher incidence of types 2 and 3 rooting patterns than the terminal cuttings. Seradix 2 application increased the prevalence of types 2 and 3 rooting patterns. Although not statistically different, cuttings dipped 2.5 cm into Seradix 2 produced more types 2 and 3 rooting patterns than cuttings dipped at the abaxial end only. Light microscopy of stem sections of cuttings indicated that roots appeared to originate from the xylem archs as well as from the cambium. The collected data indicate that it is necessary to continue research towards improving the efficiency of plantlet production of GN107 via cuttings. It appears that cuttings of this clone may be set throughout the year and that terminal cuttings should be avoided. In addition, the present practice at the Mondi Hilton nursery of treating cuttings with Seradix 2 needs to be reconsidered as although it increases rooting, it does not increase plantlet production due to its apparent inhibitory effect on shoot development. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2007.

Os agrupamentos de ferro-enxofre (Fe-S) são grupos prostéticos necessários para a manutenção da vida, pois estão envolvidos em diversos processos incluindo a transferência de elétrons, reações metabólicas, sinalização e regulação da expressão gênica. As plantas realizam fotossíntese e respiração, dois processos que requerem proteínas Fe-S, sendo os únicos organismos em que a síntese destas proteínas é compartimentalizada. Diversos fatores afetam o desenvolvimento das plantas, entre eles, a temperatura baixa, fator limitante à produtividade e à distribuição geográfica das plantas, incluindo Eucalyptus grandis, uma espécie com grande importância econômica. Neste trabalho foi realizada uma análise transcricional dos genes NFS1, ISA1 e ISU1 de E. grandis após diferentes estúmlos por meio de PCR quantitativa (qRT-PCR) e microarranjos. Após o tratamento de plântulas de E. grandis com frio, foram realizados experimentos de qRT-PCR. Os resultados foram normalizados com os genes constitutivos codificadores da histona H2B e da ribonucleoproteína L23A. Considerando tal normalização, ISU1 aumentou sua expressão em 0,6 e 1,7 vezes, NFS1 apresentou um aumento de 6 e 8 vezes, enquanto ISA1 apresentou um aumento de 69 a 114 vezes em relação à condição controle. Utilizando-se a técnica de microarranjos, foi analisada a diferença de expressão entre folhas e xilema de árvores maduras de E. grandis. O gene NFS1 apresentou maior expressão nas folhas do que em xilema, porém os genes ISA1 e ISU1 apresentaram um padrão de expressão equivalente entre os dois tipos de tecidos. Esses resultados sugerem que (i) os genes NFS1 e ISA1 podem estar relacionados à resposta celular ao estresse causado por frio; e que (ii) os aumentos na expressão devem-se, provavelmente, ao metabolismo de enxofre e à indução de enzimas antioxidantes. Foi também realizado um experimento de curva de tempo com a submissão de plântulas de E. grandis ao resfriamento, objetivando-se verificar em que momento esses genes começam a ter suas expressões aumentadas. O gene ISU1 apresentou maior expressão gênica nas primeiras duas horas de tratamento, caindo drasticamente logo após este período. O gene ISA1, que havia apresentado a maior expressão relativa no experimento anterior, não apresentou diferença significativa no padrão de expressão durante as 16 horas de resfriamento, assim como o gene NFS1. Esses resultados indicam que as proteínas Fe-S, frente ao resfriamento, estão possivelmente envolvidas na recuperação das plantas após tal estresse. / Iron-sulfur (Fe-S) clusters are prosthetic groups required for the maintenance of life because they are involved in various vital processes, including electron transfers, metabolic reactions, signaling and regulation of gene expression. Plants perform photosynthesis and respiration, two processes that require Fe-S proteins, and are the only organisms in which the synthesis of these proteins is compartmentalized. Several factors and stresses affect the development of plants including low temperature, which is a productivity-limiting factor and restricts plants to certain geographical distributions, including Eucalyptus grandis, a species with significant economic importance. The aim of this study is to perform an analysis of E. grandis NFS1 and ISA1 gene expressions after different stimuli through quantitative PCR (qRT-PCR) and microarrays. qRT-PCR experiment were conducted on plants submitted to a cold treatment. The results were normalized with the housekeeping genes encoding histone H2B and ribonucleoprotein L23A. Considering such normalizations, ISU1 increased the expression 0.6 and 1-fold, NFS1 showed a 6 and 8-fold increase in comparison with the control condition, while ISA1 gene increased 69 and 114-fold. Using microarrays, the difference in expression between leaves and xylem of E. grandis was analyzed. The NFS1 gene showed higher expression in leaves than in xylem, but the ISA1and ISU1 showed equivalent pattern of expression in both types of tissues. These results suggest that (i) NFS1 and ISA1 genes are related to the cellular response to the stress caused by chilling, and that (ii) the increased expression should be probably due to the metabolism of sulfur and to the induction of antioxidative enzymes. A time-course experiment was also conducted during the cold stress of E. grandis plants to look at which moment these genes begin to increase their expressions. The ISU1 gene showed higher expression in the first 2 hours of treatment, and than decreased severally after this period. The ISA1 gene, which had shown the highest expression in the previous experiment, did not show significant differences in the pattern of expression during the 16 hours of chilling treatment, as well as the NFS1 gene. These results indicate that Fe-S proteins, in response to low temperature, are possibly involved in the recovery of the plants after this stress.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-07-04T18:46:11Z No. of bitstreams: 1 texto completo.pdf: 3486553 bytes, checksum: 5c535a65a5befe9e9c80b880a87e59ac (MD5) / Made available in DSpace on 2017-07-04T18:46:11Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3486553 bytes, checksum: 5c535a65a5befe9e9c80b880a87e59ac (MD5) Previous issue date: 2001-06-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Este trabalho foi desenvolvido com o apoio da Empresa de Mineração Caolinita Ltda. e da Sociedade de Investigações Florestais/Universidade Federal de Viçosa, com o objetivo de recompor a paisagem degradada pela mineração de caulim na Mina do Quebra-Côco, município de Ubá, Zona da Mata de Minas Gerais, tendo os resultados sido coletados em março de 2000. O trabalho consistiu da utilização de técnicas de Sistema Agroflorestal, recomendando a consorciação de vegetação herbácea, arbustiva e arbórea, para a recomposição da paisagem degradada. Para implantação do projeto, avaliou-se a área nos seguintes aspectos: condições topográficas e climáticas, vegetação de entorno, solos e suscetibilidade à erosão. Após estes estudos, foram feitas a definição dos tratamentos e a escolha da vegetação mais adequada à situação local. As espécies utilizadas foram: Piptadenia gonoacantha, Mabea fistulifera, Mimosa flocculosa, Acacia mangium, Pinus oocarpa, Eucalyptus grandis, Saccharum officinarum, Brachiaria decumbens e Mucuna sp. Foram observadas a mitigação dos impactos visuais pela cobertura vegetal da área. O eucalipto, o jacaré e a acácia apresentaram bom desenvolvimento, devendo-se ressaltar que a bracatinga foi a única espécie que, em um ano, completou seu ciclo reprodutivo. Observaram-se, também, maior estabilidade do relevo, aumento da fertilidade do solo, início da formação superficial da camada orgânica no horizonte A e da atividade biológica dos solos e presença de insetos, fungos e outros animais, num local outrora considerado inóspito. / This work was developed with the support of the Empresa de Mineração Caolinita Ltda. and the Sociedade de Investigações Florestais/Universidade Federal de Viçosa, and its objective was to reclaim the landscape spoiled by kaolin mining in the Quebra-Côco Mine, in the municipality of Ubá, Forest Zone of the Minas Gerais State, Brasil. The results were collected in March 2000. The work was carried out by means of Agroforestry System techniques, which recommends the use of a mixture of herbaceous, bushy and arboreous vegetation for the reclamation of the spoiled landscape. For the establishment of the project, the following aspects were evaluated: topographic and climatic conditions, neighbouring vegetation, soils and erosion risks. After these studies the determination of treatments and vegetation choices was made. The species used were as follows: Piptadenia gonoacantha, Mabea fistulifera , Mimosa flocculosa , Acacia mangium, Pinus oocarpa, Eucalyptus grandis, Saccharum officinarum, Brachiaria decumbens and Mucuna sp. The visual impacts amended by means of the vegetation cover of the area were observed. Eucalyptus grandis, Piptadenia gonoacantha and Acacia mangium presented a good growth and Mimosa flocculosa was the only one that completed its reproductive cycle in one year. A greater stability of relief, an increase of soil fertility and the start of the surface formation of the organic layer in the A horizon, besides biologic activity in the soils and the presence of insects, fungi and other animals were observed in an area considered inhospitable. / Dissertação importada do Alexandria

As proteínas Dof (ligação ao DNA com um dedo, do inglês, DNA binding with One Finger) compreendem uma família de fatores de transcrição exclusiva de plantas, caracterizadas pela presença de um domínio de ligação ao DNA semelhante ao domínio ‘dedo-de-zinco’. Estas proteínas estão associadas a diferentes processos biológicos vegetais como germinação, florescimento e outros. O objetivo principal do presente trabalho foi a caracterização funcional de três fatores de transcrição Dof de Eucalyptus grandis a fim de avaliar a função dos mesmos na biogênese do sistema vascular desta planta. Baseado em resultados prévios do nosso grupo, foram escolhidos três genes (EgD01698, EgD00607 e EgK00405) que apresentaram um perfil de expressão significativo em tecidos vasculares de caules de E. grandis e, também, alta homologia a genes Dof previamente caracterizados em tecidos vasculares de outros vegetais. As regiões codificadoras desses genes foram amplificadas por PCR e clonadas no vetor de entrada pENTR/D-TOPO (Invitrogen). Por recombinação, os genes foram transferidos para o vetor pH7WG2D (VIB) para expressão em Arabidopsis thaliana. Os genes Dof também foram clonados no vetor pGEX-4T-1 (GE Healthcare) para a expressão heteróloga em Escherichia coli Plantas de A. thaliana foram transformadas com os vetores binários pelo método de imersão floral e as sementes foram selecionadas com o antibiótico higromicina. Apenas duas plantas para o gene D00607 e duas para o gene K00405 foram obtidas. As plantas transgênicas estão atualmente sob cultivo para serem geradas linhagens homozigotas e, assim, caracterizadas molecularmente. Além disso, a localização subcelular foi verificada pela expressão transiente de Dof::GFP em folhas de Nicotiana benthamiana. A expressão de GFP foi detectada difusa no citoplasma e no núcleo. Entretanto, esses ensaios deverão ser repetidos para confirmação dos resultados. Em paralelo, células de E. coli BL21 (DE3) pT-GroE foram transformadas com os vetores pGEX-4T-1-D01698 e pGEX-4T-1-D00607. A expressão gênica foi induzida durante 20 h a 20oC com 1 mM IPTG. As proteínas foram detectadas na fração solúvel por SDS-PAGE e western blot e, posteriormente, purificadas por cromatografia de afinidade. A expressão bem sucedida das proteínas Dof em E. coli permitirá a produção dessas proteínas para futuros estudos de caracterização funcional. / DNA binding with one finger (Dof) proteins comprehend a family of plant exclusive transcription factors characterized by the presence of the Dof DNA binding domain whose structure is similar to the zinc finger domain. They are associated with diverse biological plant processes such as germination, flowering and many others. The aim of this work was to functionally characterize three Dof genes from Eucalyptus grandis in order to evaluate their role in the biogenesis of vascular system. Based on previous results related to the E. grandis Dof gene family studies obtained by our group, we chose three genes (D01698, D00607 and K00405) with higher expression profile in vascular tissues of E. grandis stalk, as well as with higher homology to Dof genes previously characterized as critical to the genesis of vascular tissues. The CDS of these genes were amplified by PCR and cloned into pENTR/D-TOPO entry vector (Invitrogen). Via recombination, Dof genes were then transferred to the pH7WG2D binary vector (VIB) for the expression in Arabidopsis thaliana. They were also cloned into the pGEX-4T-1 vector (GE Healthcare) for Escherichia coli recombinant gene expression. A. thaliana plants were genetically transformed with recombinant binary plasmids by the floral dip method and seeds were selected by hygromycin resistance Only two plants for the D00607 gene and two plants for the K00405 gene were obtained. Plants are being cultivated in order to obtain homozygous individuals and they will be molecularly characterized. Additionally, subcellular localization was verified by transient expression of Dof::GFP in Nicotiana benthamiana and the expression of GFP was detected at the cytoplasm and nucleus. However, these assays need to be repeated in order to confirm the previous results. In parallel, E. coli BL21 (DE3) pT-GroE cells were transformed with pGEX-4T-1- D01698 and pGEX-4T-1-D00607. Gene expression was induced for 20 h at 20 oC with 1 mM IPTG for protein production. Proteins were detected in the soluble fraction by SDS-PAGE and western blot analysis and then were purified by affinity chromatography. The successful expression of Dof proteins in E. coli provides a way to produce these proteins for future functional characterization studies.