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Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-06-06T14:03:30Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_fernanda_reolon_tonel.pdf: 1524534 bytes, checksum: 4326518bd7bd55acb90e0f2630de6ac4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-06T14:30:22Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_fernanda_reolon_tonel.pdf: 1524534 bytes, checksum: 4326518bd7bd55acb90e0f2630de6ac4 (MD5) / Made available in DSpace on 2017-06-06T14:30:22Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_fernanda_reolon_tonel.pdf: 1524534 bytes, checksum: 4326518bd7bd55acb90e0f2630de6ac4 (MD5) Previous issue date: 2014-12-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O estudo objetivou avaliar a capacidade fitorremediadora do trevo vermelho (Trifolium pratense L.) e do feijão miúdo (Vigna unguiculata L.) a compostos derivados de petróleo. Foram realizados experimentos em laboratório e em casa de vegetação, onde as sementes das duas espécies foram expostas as concentrações de 0,0; 0,1; 0,2 e 0,3 % (v/v) de óleo diesel e em seguida submetidas às análises de viabilidade, vigor e atividade de enzimas hidrolíticas. Em uma segunda etapa, as duas espécies, foram submetidas à contaminação por 0,0; 0,5; 1,0 e 1,5 % (v/v) de óleo diesel. O trevo vermelho foi cultivado durante 112 dias e a partir de coletas periódicas foram realizadas análises de parâmetros de crescimento, teor de pigmentos fotossintéticos, anatomia foliar e radicular e análise de enzimas antioxidantes. O feijão miúdo permaneceu em casa de vegetação durante 60 dias, para as análises periódicas dos parâmetros de crescimento, teor de pigmentos fotossintéticos, fotossíntese e enzimas antioxidantes. Para ambas, no início e no final do experimento foi realizada análise de hidrocarbonetos de petróleo no substrato de cultivo. Os resultados obtidos mostraram maior sensibilidade das duas espécies submetidas ao contaminante em condições controladas, no entanto, a influência negativa foi observada apenas nas maiores concentrações do composto tóxico. Os demais parâmetros foram diferentemente influenciados nas duas espécies, destacando-se para ambas, os efeitos negativos ocorridos na maior concentração de óleo diesel (1,5 % (v/v)) e benefícios ocasionados na menor concentração (0,5 % (v/v)). Portanto, os efeitos fisiológicos ocasionados permitiram a determinação do limite de tolerância das plantas de trevo vermelho e feijão miúdo ao óleo diesel. A eficiência na remoção dos compostos tóxicos, verificada para as duas espécies permitiu a confirmação de ambas como fitorremediadoras de compostos derivados de petróleo. / The study aimed to evaluate the phytoremediation capacity of red clover (Trifolium pratense L.) and cowpea (Vigna unguiculata L.) derived from petroleum compounds. Experiments were conducted in laboratory and greenhouse, where the seeds of both species concentrations of 0.0 were exposed; 0.1; 0.2 and 0.3% (v/v) of diesel and then subject to feasibility analysis, strength and activity of hydrolytic enzymes. In a second step, the two species were submitted to contamination by 0.0; 0.5; 1.0 and 1.5 % (v/v) of diesel oil. Red clover was grown for 112 days and from periodic samples were taken analyzes of growth parameters, photosynthetic pigments content, leaf and root anatomy and analysis of antioxidant enzymes. Cowpea remained in a greenhouse for 60 days for regular reviews of the growth parameters, photosynthetic pigments content, photosynthesis and antioxidant enzymes. For both the beginning and end of the experiment was performed petroleum hydrocarbon analyzer in the cultivation substrate. The results showed higher sensitivity of both the dopant species under controlled conditions, however, the negative effect was observed only at higher concentrations of the toxic compound. The other parameters were influenced differently in the two species, standing out for both the negative effects occurring in the highest concentration of diesel (1.5 % (v/v)) and benefits incurred in lower concentration (0.5 % (v/v)). Therefore, the physiological effects caused allowed the determination of the tolerance limit for red clover plants and cowpea to diesel oil. The efficiency of removal of toxic compounds found in these species permitted confirmation both as phytoremediator of petroleum compounds.

Two conceptual approaches which offer promise for improved understanding of biological invasions are conceptualizing the invasion process as a series of distinct stages and explicitly incorporating human actions into analyses. This study explores the utility of these approaches for understanding the invasion of Trifolium (true clover) species in New Zealand. From the published literature, I collected a range of Trifolium species attributes, including aspects of global transport and use by humans, opportunistic association with humans in New Zealand, native range attributes, habitat characteristics, and biological traits. I also searched historical records to estimate the extent to which each species had been planted in New Zealand, a search facilitated by the enormous importance of Trifolium in New Zealand’s pastoral agriculture system. Regression analysis and structural equation modelling were then used to relate these variables to success at each invasion stage. Fifty-four of the 228 species in the genus Trifolium were intentionally introduced to New Zealand. Species introduced for commercial agriculture were characterised by a large number of economic uses and presence in Britain, while species introduced for horticulture or experimental agriculture were characterised by a large native range area. Nine of these 54 intentionally introduced species subsequently naturalised in New Zealand. The species that successfully naturalised were those that had been planted extensively by humans and that were well-matched to the New Zealand climate. A further 16 species (from the pool of 174 species that were never intentionally introduced) arrived and naturalised in New Zealand without any recorded intentional aid of humans. Several attributes appeared to assist species in unintentional introduction-naturalisation, including a good match to the New Zealand climate, a large native range area, presence in human-influenced habitats, a widespread distribution in Britain, and self-pollination capability. The 25 total naturalised species varied greatly in their current distributions and in the rates at which they had spread to achieve those distributions. Species that had spread quickly and are currently more widespread had been frequent contaminants in the pasture seed supply and have a long flowering period in New Zealand. Other biological traits and native range attributes played supporting roles in the spread process. Attributes facilitating success clearly varied among invasion stages. Humans played a dominant role at all stages of this invasion, although biological traits had increasing importance as a species moved through the invasion sequence. My findings suggest that incorporation of human actions and the stage-based framework provide valuable insight into the invasion process. I discuss potential avenues by which these approaches might be integrated into predictive invasion models.

Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants organiques persistants potentiellement mutagènes et cancérigènes. Leur transfert de l'atmosphère vers les écosystèmes, notamment vers les plantes, conditionne leur entrée dans les chaines alimentaires mais les modalités de ce transfert restent encore mal connues. L'objectif de ce travail était donc de caractériser le transfert et d'identifier les effets biologiques des HAP atmosphériques sur un système sol-plante-microorganismes symbiotiques.Un dispositif expérimental a été conçu afin de recréer en laboratoire une pollution atmosphérique par les HAP avec comme HAP modèle le phénanthrène (PHE). Le dispositif a fait l'objet d'une validation et d'une calibration élaborée de manière originale par une double approche mêlant l'expérimental à la simulation mathématique. Les niveaux d'exposition en polluant (150 µg m-3), contrôlés par des échantillonneurs passifs, se sont avérés pertinents par rapport aux conditions in situ. Ce dispositif a donc été utilisé pour exposer durant un mois des microsystèmes sol-plante-microorganismes au PHE par voie atmosphérique.Les différentes études ont mis en évidence un transfert du PHE depuis l'atmosphère vers tous les compartiments du microsystème, avec une accumulation majeure vers les feuilles de trèfle ou de ray-grass (respectivement 170 et 70 µg g־ ¹MS) et un transfert phloémien vers les racines est suggéré. Chez le trèfle, la mycorhization n'a pas été affectée, tandis que le nombre de nodules actifs a diminué de manière significative. Contrairement aux racines, la biomasse aérienne du trèfle a été significativement affectée (environ - 25%) par l'exposition au PHE atmosphérique, suggérant un impact sur le métabolisme carboné de la plante. Une expérience de marquage des trèfles au ¹³C-CO2 a effectivement montré un impact négatif du PHE atmosphérique sur la croissance, l'allocation de biomasse et l'allocation carbonée. Pour conclure, ces études ont permis non seulement de caractériser les effets biologiques et physiologiques des HAP atmosphériques sur les végétaux mais également de proposer l'utilisation du potentiel mycorhizien comme indicateur de pollution atmosphérique par les HAP.

The factors influencing senescence in white clover (Trifolium repens L.) are of considerable importance to the pastoral sector of New Zealand’s economy. The plant hormones, ethylene and the cytokinins, have been implicated as having opposing influences on senescence. This project focused on the cytokinins. The rate limiting step in cytokinin biosynthesis is catalysed by isopentenyl transferase (IPT) and the primary enzyme in the degradation of cytokinins is cytokinin oxidase/dehydrogenase (CKX). Both IPT and CKX genes are present as multi-gene families. A reduction in the level of active cytokinins either via a decrease in IPT expression, or an increase in CKX expression, or both, would implicate the cytokinins in developmental leaf senescence in white clover. White clover grows in a sequential pattern with leaves at all stages of development making it a good model for studying leaf development and senescence. A decrease in leaf chlorophyll is used as a marker for the onset of senescence. A micro-scale chlorophyll analysis was developed using the NanoDrop™ thus allowing tissue from the same leaflet to be used for gene expression and chlorophyll measurements. The pattern of chlorophyll changes was similar to that shown by Hunter et al.(1999) and Yoo et al.(2003) in white clover stolons used for ethylene research. Reverse transcriptase PCR (RT-PCR) and BLAST analysis was used to identify five putative IPT genes and seven putative CKX genes from white clover. RT-PCR demonstrated the expression of seven of these genes (TrIPT1. TrIPT13, TrIPT15 TrCKX1, TrCKX2, TrCKX6). Analysis with quantitative real-time PCR showed expression of TrCKX2 increased markedly during leaf expansion and was consistently high during senescence, suggesting a potential role for CKX in facilitating the progression of senescence.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Abstract The main objective of this thesis was to investigate tree - cover crop interactions and soil response in an intercropping system, in which leguminous and grass cover crops were used with birch (red-leaved Downy birch Betula pubescens L.). The investigation was conducted in two field experiments in a nursery and in a greenhouse experiment. In the latter the effect of the water supply in interspesific competition was also investigated. The cover crops in the field experiments were perennial clovers Trifolium pratense L., T. repens L. and T. hybridum L. and annual clovers T. incarnatum L., T. resupinatum L. and T. subterraneum L. and perennial Festuca rubra L. The height, stem diameter, leaf area and nutrient status of the birch were determined, as well as soil nutrient status and microbial characteristics. The cover crops in the greenhouse experiment were T. repens, T. subterraeum and F. rubra. The biomass, height, leaf area, leaf area index, specific leaf area and N concentration of the birch, the biomass and N concentration of the cover crops were measured, and soil N and microbial characteristics, as well. Bare ground was the control in all the experiments. The perennial clovers and Festuca strongly decreased the birch growth and nutrient status, but the annual clovers sown in midsummer in the field experiments provided about as good growth as bare ground. In the greenhouse experiment all cover crops were effective competitors with the birch. The soil NO3-N was, in general, the highest on bare ground and second highest in the annual clover plots. Though there were, in general, only minor differences in the soil nutrient concentrations between the treatments, there were significant differences in the tree growth and nutrient concentrations. The interspecific competition in this kind of intercropping system is mainly belowground. The growth reduction in the birch was mainly due to competition for nitrogen but water seems to play an important role in regulating the competitive interaction between the birch and cover crops. The competition for these resources seems to be most crucial at the beginning of the growing season. The microbial biomasses and soil respiration were greatest in the Festuca and perennial clover treatments, which may indicate that microorganisms together with these cover crops may seriously compete with birch for nutrients. Intercropping system is complex and comprises both negative and positive influences. In order to minimize negative competition effects, the cover crop should be non-competitive or the ground should be kept free of vegetation at the beginning of the growing season. By improving soil microbial characteristics, the vegetative ground covers make this cropping system one possiblity towards sustainability in the long-term.

Previous field research show, that late successional species correspond with soil development, especially with organomineral A horizon developing. Aim of my thesis was to compare plant growth on different types of soil from spoil heaps. They were taken from three chronosequencies of different age - nonrecultivated and soils recultivated with planting of alder (Alnus) and spruce (Picea). In my research were used 7 types of plants - Arrhenatherum elatius, Centaureae jacea, Festuca rubra, Lychnis flos-cuculi, Lotus corniculatus, Plantago major, Trifolium medium. Spontaneous sites support more species than reclaimed ones this difference increase with plot age without distinct difference between early and late succession species. Key words Succession, recultivation, germination alder (Alnus), spruce (Picea), Arrhenatherum, Centaureae, Festuca, Lychnis, Lotus, Plantago, Trifolium.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this research was to evaluate tree pasture-based systems (PS) with elephant grass (EG) + spontaneous growing species (SGS), ryegrass (RG), for PS1; EG + SGS + forage peanut, for PS2; and EG + SGS + RG + red clover, for PS3. EG was planted 4 m spaced rows. In the cool-season, ryegrass was sowed between rows of EG; red clover was sowed and the forage peanut was preserved in respectively PS. Experimental design was completely randomized with tree treatments (SF), two replicates (paddocks) in completely split-plot time (grazing cycles). Holstein cows receiving 5.5 kg-daily and a complementary concentrate feed were used in the evaluation. The herbage mass parameters, botanical composition, forage production and stocking rate were evaluated. Samples were collected by the hand-plucking method to analyze the organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and organic matter in situ digestibility (OMISD) of pasture; phenols and tannins on legumes. Nine grazing cycle were performed during the experimental period (341 days). The mean values of forage production, stocking rate, crude protein and digestibility were 17.14; 16.80; and 19.47 t/ha; 3.28; 3.34; and 3.60 UA/ha; 13.86; 15.39; and 14.78%; 78.33; 79.23; and 79.94% on the respective PS. SGS increased significantly (P≤0,05) relation to the PS without forage legume. Similar results were observed for forage production OM an NDF in comparison to PS. Nutritive value was similar between forage legumes. Differences (P≤0,05) on condensed tannin tenors were observed between forage legumes. Considering the forage production, stocking rate and nutritive value, the PS mixed to forage legumes showed better performance. / O objetivo desta pesquisa foi avaliar três sistemas forrageiros (SF) com capim elefante (CE), espécies de crescimento espontâneo (ECE), azevém anual (AZ), como SF1; CE + ECE + AZ + amendoim forrageiro (AF), como SF2; e CE + ECE + AZ + trevo vermelho (TV), como SF3. O capim elefante foi estabelecido em linhas afastadas a cada 4 m. No período hibernal fez-se o estabelecimento do AZ entre as linhas do capim elefante; o trevo vermelho foi semeado e o amendoim forrageiro foi preservado, considerando os respectivos tratamentos. O delineamento experimental foi o inteiramente casualizado, com três tratamentos (SF), duas repetições (piquetes) em parcelas subdivididas no tempo (pastejos). Para avaliação foram usadas vacas da raça Holandesa que receberam complementação alimentar com concentrado à razão de 5,5 kg/dia. Foram avaliados parâmetros da massa de forragem pré-pastejo, a composição botânica, a produção de forragem e a lotação. Para analisar a matéria orgânica (MO), a fibra em detergente neutro (FDN), proteína bruta (PB) e digestibilidade in situ da MO (DISMO) da pastagem e os teores de fenóis e taninos das leguminosas, foram coletadas amostras de pastejo simulado. Durante o período experimental (341 dias) foram efetuados nove ciclos de pastejo. Os valores médios de produção de forragem, lotação, PB e de DISMO foram 17,14; 16,80; e 19,47 t/ha; 3,28; 3,34; e 3,60 UA/ha; 13,86; 15,39; e 14,78%; 78,33; 79,23; e 79,94% nos respectivos SF. Houve aumento significativo (P≤0,05) para espécies de crescimento espontâneo na pastagem sem leguminosa. Resultados similares foram observados entre SF para MO e FDN. O valor nutritivo foi similar entre as leguminosas forrageiras. Foram observadas diferenças (P≤0,05) entre as leguminosas para os teores de taninos condensados. Considerando a massa de forragem, a lotação e o valor nutritivo, as pastagens consorciadas com leguminosas forrageiras apresentaram melhor desempenho.