Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Grape quality is linked to the organoleptic properties of grapes, raisins and wine. Many advances have been made in understanding the grape components that are important in the quality of wines and other grape products. A better understanding of the compositional content of grapes entails knowing when and how the various components accumulate in the berry. Therefore, an appreciation of grape berry development is vitally important towards the understanding of how vineyard practices can be used to improve the quality of grapes and eventually, wines. The more established methods for grape berry quality assessment are based on gravimetric methods such as colorimetry, fluorescence and chromatography. These conventional methods are accurate at targeting particular components, but are typically multi-step, destructive, expensive, polluting procedures that might be technically challenging. Very often grape berries are evaluated for quality (only) at harvest. This remains a necessary exercise as it helps viticulturists and oenologists to estimate some targeted metabolite profiles that are known to greatly influence chemical and sensory profiles of wines. However, a more objective measurement of predicting grape berry quality would involve evaluation of the grapes throughout the entire development and maturation cycle right from the early fruit to the ripe fruit. To achieve this objective, the modern grape and wine industry needs rapid, reliable, simpler and cost effective methods to profile berry development. By the turn of the last millennium, developments in infrared instrumentation such as Fourier-transform infrared (FT NIR) and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR) in combination with chemometrics resulted in the development of rapid methods for evaluating the internal and external characteristics of fresh fruit, including grapes. The advancement and application of these rapid techniques to fingerprint grape compositional traits would be useful in monitoring grape berry quality. In this project an evaluation of grape berry development was investigated in a South African vineyard setting. To achieve this goal, Sauvignon blanc grape berry samples were collected and characterised at five defined stages of development: green, pre-véraison, véraison, post-véraison and ripe. Metabolically inactivated (frozen in liquid nitrogen and stored at -80oC) and fresh berries were analysed with FT-IR spectroscopy in the near infrared (NIR) and mid-infrared (MIR) ranges to provide spectral data. The spectral data were used to provide qualitative (developmental stage) and quantitative (metabolite concentration of key primary metabolites) information of the berries. High performance liquid chromatography (HPLC) was used to separate and quantify glucose, fructose, tartaric acid, malic acid and succinic acid which provided the reference data needed for quantitative analysis of the spectra. Unsupervised and supervised multivariate analyses were sequentially performed on various data blocks obtained by spectroscopy to construct qualitative and quantitative models that were used to characterise the berries. Successful treatment of data by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) gave statistically significant chemometric models that discriminated the berries according to their stages of development. The loadings from MIR models highlighted the important discriminant variables responsible for the observed developmental stage classification. The best calibration models to predict metabolite concentrations were obtained from MIR spectra for glucose, fructose, tartaric acid and malic acid. The results showed that both NIR and MIR spectra in combination with multivariate analysis could be reliably used to evaluate Sauvignon blanc grape berry quality throughout the fruit’s development cycle. Moreover, the methods used were fast and required minimal sample processing and no metabolite extractions with organic solvent. In addition, the individual major sugar and organic acids were accurately predicted at the five stages under investigation. This study provides further proof that IR technologies are robust and suitable to explore high-throughput and in-field application of grape compound profiling. / AFRIKAANSE OPSOMMING: Druifkwaliteit word gekoppel aan die organoleptiese eienskappe van druiwe, rosyntjies en wyn. Baie vooruitgang is reeds gemaak in die begrip van druifkomponente wat belangrik is vir die kwaliteit van wyn en ander druifprodukte. ’n Beter begrip van die samestellende inhoud van druiwe behels om te weet wanneer en hoe die verskeie komponente in die korrel opgaar. ’n Evaluasie van druiwekorrel-ontwikkeling is dus uiters belangrik vir ’n begrip van hoe wingerdpraktyke gebruik kan word om die kwaliteit van druiwe, en uiteindelik van wyne, te verbeter. Die meer gevestigde maniere vir die assessering van druiwekorrelkwaliteit is gebaseer op gravimetriese metodes soos kolorimetrie, fluoressensie en chromatografie. Hierdie konvensionele metodes is akkuraat om spesifieke komponente te teiken, maar behels tipies veelvuldige stappe en is prosesse wat destruktief en duur is, besoedeling veroorsaak, asook moontlik tegnies uitdagend is. In baie gevalle word druiwekorrels (eers) tydens oes vir kwaliteit geëvalueer. Hierdie is steeds ’n noodsaaklike oefening omdat dit wingerdkundiges en wynkundiges help om die metabolietprofiele wat daarvoor bekend is om ’n groot invloed op die chemiese en sensoriese profiele van wyn te hê en dus geteiken word, te skat. ’n Meer objektiewe meting om druiwekorrelkwaliteit te voorspel, sou die evaluering van die druiwe dwarsdeur hulle ontwikkeling- en rypwordingsiklus behels, vanaf die vroeë vrugte tot die ryp vrugte. Om hierdie doelwit te behaal, benodig die moderne druiwe- en wynbedryf vinnige, betroubare, eenvoudiger en kostedoeltreffende metodes om ’n profiel saam te stel van korrelontwikkeling. Aan die einde van die vorige millennium het ontwikkelings in infrarooi instrumentering soos Fourier-transform infrarooi (FT NIR) en attenuated total reflectance Fourier-transform infrarooi spektroskopie (ATR FT-IR) in kombinasie met chemometrika gelei tot die ontwikkeling van vinnige metodes om die interne en eksterne kenmerke van vars vrugte, insluitend druiwe, te meet. Die vooruitgang en toepassing van hierdie vinnige tegnieke om ‘vingerafdrukke’ te bekom van die samestellende kenmerke sal nuttig wees vir die verbetering van druiwekorrelkwaliteit. In hierdie projek is ’n evaluering van druiwekorrelontwikkeling in ’n Suid-Afrikaanse wingerdligging ondersoek. Ten einde hierdie doel te bereik, is Sauvignon blanc druiwekorrelmonsters op vyf gedefinieerde stadiums van ontwikkeling versamel en gekarakteriseer: groen, voor deurslaan, deurslaan, ná deurslaan en ryp. Metabolies geïnaktiveerde (bevrore in vloeibare stikstof en gestoor teen -80oC) en vars korrels is met FT-IR spektroskopie in die naby infrarooi (NIR) and mid-infrarooi (MIR) grense geanaliseer om spektrale data te verskaf. Die spektrale data is gebruik om kwalitatiewe (ontwikkelingstadium) en kwantitatiewe (metabolietkonsentrasie van belangrikste primêre metaboliete) inligting van die korrels te verskaf. High performance liquid chromatography (HPLC) is gebruik om glukose, fruktose, wynsteensuur, appelsuur en suksiensuur te skei en te kwantifiseer, wat die verwysingsdata verskaf het wat vir die kwantitatiewe analise van die spektra benodig word. Ongekontroleerde en gekontroleerde meervariantanalises is opeenvolgend op verskeie datablokke uitgevoer wat met spektroskopie verkry is om kwalitatiewe en kwantitatiewe modelle te verkry wat gebruik is om die korrels te karakteriseer. Suksesvolle behandeling van die data deur hoofkomponent analise (principal component analysis (PCA)) en ortogonale parsiële kleinstekwadraat diskriminant analise (partial least squares discriminant analysis (OPLS-DA)) het statisties betekenisvolle chemometriese modelle verskaf wat die korrels op grond van hulle ontwikkelingstadia onderskei het. Die ladings vanaf die MIR-modelle het die belangrike diskriminantveranderlikes beklemtoon wat vir die klassifikasie van die waargenome ontwikkelingstadium verantwoordelik is. Die beste kalibrasiemodelle om metabolietkonsentrasies te verkry, is vanuit die MIR-spektra vir glukose, fruktose, wynsteensuur en appelsuur bekom. Die resultate toon dat beide die NIR- en MIR-spektra, in kombinasie met meervariantanalise, betroubaar gebruik kan word om Sauvignon blanc druiwekorrelkwaliteit dwarsdeur die vrug se ontwikkelingsiklus te evalueer. Verder is die metodes wat gebruik word, vinnig en het hulle minimale monsterprosessering en geen metabolietekstraksies met organiese oplosmiddel benodig nie. Daarbenewens is die vernaamste suiker en organiese sure individueel akkuraat voorspel op die vyf stadia wat ondersoek is. Hierdie studie verskaf verdere bewys dat IR-tegnologieë robuus en geskik is om hoë-deurset en in-veld toepassings van profielsamestelling van druiweverbindings te ondersoek.

Le déterminisme de la formation de la grappe reste parmi les phénomènes les moins bien précisés de la physiologie de la Vigne. La question a été abordée de plusieurs façons mais les éléments de réponse obtenus ne permettent pas encore de se faire une idée synthétique des mécanismes fondamentaux qui produisent l’apparition des primordia inflorescentiels (PI) en année N-1 et qui pourraient régir jusqu’à 65 à 70% du rendement final en année N. Notre étude s’est donc focalisée sur (i) la caractérisation du processus de formation des PI dans les bourgeons latents de vigne (Vitis vinifera L. Merlot) et la redéfinition de la constitution du rendement, (ii) la compréhension des mécanismes d’initiation et de différenciation des PI et (iii) l’évaluation des impacts de différents facteurs (ABA exogène, lumière et effeuillage) sur ces mécanismes.Cette étude intégrale combinant des approches multi-échelles et multi-disciplinaires a permis dans un premier temps de mettre en évidence le déterminisme de la phase d’induction inflorescentielle dans la construction du rendement en identifiant trois phases clés du processus de formation des PI et en y intégrant une nouvelle notion qu’est le « degré de ramification des PI » ; puis dans un second temps, de proposer certains modes de régulation des mécanismes d’initiation et de différenciation des PI en identifiant trois types de marqueurs précoces de la fertilité potentielle : des marqueurs moléculaires (VvCLE25-1, VvTFL1a et VvMFT1), biochimiques (équilibre CKs/AIA, D-glucose et amidon), et environnementaux (ensoleillement et température journaliers cumulés). L’ensemble des résultats pourra contribuer au développement d’un outil prédictif précoce de la « fertilité potentielle » (et donc du rendement probable maximum) afin de mieux guider et gérer la taille et les pratiques culturales. / The grape cluster formation determinism remains the one of the undefined phenomena in grapevine physiology process. The topic has been tackled in multiple ways. However, based on all the known information, we still are not allowed to get a synthetic idea of the fundamental mechanisms that produce the appearance of inflorescential primordia in year N-1 and which could govern up to 65 to 70 % of final yield in year N. Our study focuses thus on (i) the characterization of IP formation process in grapevine latent buds (Vitis vinifera L. Merlot) and the redefinition of yield constitution, (ii) understanding IP initiation and differentiation mechanisms, and (iii) evaluating the impacts of different factors (exogenous ABA, light and leaf removal) on these mechanisms.This comprehensive study, which combines multi-scale and multi-disciplinary approaches, firstly allowed us to highlight the determinism of inflorescence induction phase in yield construction by identifying three key phases in IP formation process and by incorporating a new notion which is "IP branching degree". Secondly, it proposed certain modes of regulation of IP initiation and differentiation mechanisms by identifying three types of early markers of bud fruitfulness: molecular markers (VvCLE25-1, VvTFL1a and VvMFT1), biochemical markers (CKs/IAA balance, D-glucose and starch), and environmental markers (cumulative daily sunshine and temperature).The all-inclusive results contribute to the development of an early predictive tool of "bud fruitfulness" (and thereby the probable maximum yield) to better guide and manage the grapevine training and other cultural practices.

O cultivo de plantas das espécies de Vitis (Vitaceae), conhecidas popularmente como videiras, representa uma das atividades econômicas mais proeminentes no Sul do Brasil. Figuram entre as espécies mais ricas em compostos polifenólicos, sendo os mesmos responsáveis por inúmeras atividades biológicas e farmacológicas importantes, dentre as quais, a antioxidante. Neste contexto, este trabalho objetivou analisar quali e quantitativamente os principais grupos polifenólicos encontrados em extratos de videiras, os antocianos e flavonóides, bem como realizar ensaio para avaliação da atividade antioxidante in vitro. Neste sentido foram desenvolvidos e validados dois métodos por cromatografia líquida de alta eficiência, com detector UV/VIS. A análise dos compostos fenólicos incluíram a utilização de duas colunas diferentes, sendo uma constituída por sílica C18 e outra RP-18 com partículas híbridas contendo ligações etano-silicone. Em ambos os métodos foram utilizados sistema de eluição em gradiente, cuja composição das fases móveis foram água e acetonitrila acificadas com ácido trifluoracético. Os métodos desenvolvidos foram validados segundo as normas vigentes e atenderam aos parâmetros de validação como especificidade, linearidade, precisão, sensibilidade, exatidão e robustez nas faixas de concentração avaliadas. O presente estudo também investigou a atividade antioxidante in vitro dos extratos de videira através do método potencial antioxidante reativo total (TRAP), o qual foi otimizado e validado segundo normas internacionais, utilizando Trolox como referência. A partir deste método também foi possível avaliar a reatividade total antioxidante (TAR). Todas as concentrações testadas apresentaram reatividade instantânea inferior ao composto de referência, entretanto, demonstraram atividade antioxidante superior ao Trolox 200 nM. / The cultivation of plants from Vitis species (Vitaceae), popularly known as grapevine, is one of the most prominent economic activities in southern Brazil. The Vitis species is one of the plants that is most rich in polyphenolic compounds, responsible for numerous important pharmacological and biological activities, such as antioxidant activity. In this context, this study aimed to analyze qualitatively and quantitatively the principal groups encountered in grapevine extracts, the anthocyans and flavonoids, and to assay their antioxidant activities in vitro. For this purpose, two methods were developed and validated using high-performance liquid chromatography, employing a UV/VIS detector. The analysis of phenolic compounds included the utilization of two different columns: a column constituted by silica C18 and other RP18 column with bridged ethane-silicon hybrid particles. In both methods, a gradient system was used, with water and acetonitrile acidified with trifluoroacetic acid as a mobile phase. The methods developed were validated according to ICH evaluating parameters such as specificity, linearity, precision, sensibility, accuracy and robustness in the concentration range evaluated. The present study also analyzed the antioxidant activity in vitro of grapevine extracts employing the Total Reactive Antioxidant Potencial (TRAP) method, which was optimized and validated according to international patterns, using Trolox as a reference substance. This method also allowed evaluation of the total instantaneous reactivity (TAR). In all concentrations, the samples presented lower instantaneous reactivity than that of the reference compound. In contrast, the samples presented higher antioxidant activity than Trolox 200 nM.

Traditional vineyard floor management in humid regions consists of mown perennial grass or mown resident vegetation in aisles. Many vineyard sites in the eastern USA have climate and soil that support excessive vine vigor and rapid growth of aisle vegetation. Frequent mowing or unmanaged aisles are not a practical option. To explore vineyard floor management options for vine vigor and weed management while maintaining soil cover, vine balance, and fruit quality in the eastern USA, seven cover crop treatments: 1) grower control mown tall fescue (Festuca arundinacea L.), 2) chemically mown tall fescue (Festuca arundinacea), 3) little barley (Hordeum pusillum Nutt.), 4) downy brome (Bromus tectorum L.), 5) oilseed radish (Raphanus sativus L.), 6) spring oats (Avena sativa L.), 7) chemically mown sorghum-sudangrass (Sorghum bicolor L. Moench sp.) were established for the 2011 and 2012 growing seasons in a commercial Cabernet franc vineyard, planted in 2000, in southern Illinois, on an Menfro silt loam soil. In fall 2011, oilseed radish reduced the fresh weight of grapevine shoots removed with summer hedging 46% compared to the grower control. In 2012, spring oats increased the weight of grapevine shoots removed with summer hedging 160% compared to the grower control. In 2012, spring oats, and chemically mown sorghum-sudangrass produced 82% and 73%, respectively, greater pruning weights compared to grower control mown fescue, also, spring oats, downy brome, and chemically mown sorghum-sudangrass produced 54%, 48%, and 50%, respectively, greater yields compared to the grower control in 2012. Cover crop did not affect Ravaz index in 2011 or 2012. Chemically mown sorghum-sudangrass reduced total soluble solids in grape must 7% compared to the grower control in 2012. Downy brome produced the most ground cover and greatest weed control at bloom time in 2011 and 2012, and harvest time in 2011. In 2012, oilseed radish at veraison and harvest time produced 97% and 177%, respectively, more ground cover than grower control. The persistent mulch produced by little barley and downy brome followed by burndown herbicide, Rely ® (glufosinate 1 lb ai/gal) 76 fl oz/acre in August reduced their average weed cover by a range of 99% to 89% compared to all other treatments except grower control at harvest 2012. Downy brome established in vineyard aisles had the greatest potential for maintaining weed control at bloom and harvest time, while increasing yield without decreasing vine size. However, more research is needed to develop a residue management program which encourages self-reseeding of downy brome and little barley. In a season with above average rainfall, oilseed radish reduced excessively vigorous vine growth. While all treatments studied had the potential for vineyard use, downy brome and oilseed radish had the most potential to be readily incorporated into practical vineyard aisle management systems provided they are managed to produce moderate vine size, without adverse effects to yield or fruit quality, while still maintaining effective weed control.

Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-10-05Bitstream added on 2014-06-13T19:43:10Z : No. of bitstreams: 1 menezes_acp_dr_botfca.pdf: 701350 bytes, checksum: 6123fc27fa833d40b071d8d498164c0c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho foi conduzido na Fazenda Cooperyama – Juazeiro- BA, com o objetivo de estudar a eficiência de reguladores vegetais na brotação e características dos cachos da uva ‘Itália’. Para avaliação da brotação das gemas foram efetuadas observações em dias alternados determinando-se o número de brotos. Os tratamentos considerados foram: T1: Testemunha; T2: 2,45 g L-1 de cianamida hidrogenada; T3: 0,045 mg L-1 de cinetina, 0,025mg L-1 de ácido giberélico e 0,025 mg L-1 de ácido indolilbutírico; T4: 0,09 mg L-1 de cinetina, 0,05 mg L-1 de ácido giberélico e 0,05 mg L-1 de ácido indolilbutírico; T5: 0,045 mg L-1 de cinetina, 0,025mg L-1 de ácido giberélico e 0,025 mg L-1 de ácido indolilbutírico + 10 kg de nitrogênio e 9 kg de Ca ha-1; T6: 0,09 mg L-1 de cinetina, 0,05mg L-1 de ácido giberélico e 0,05 mg L-1 de ácido indolilbutírico + 10 kg de nitrogênio e 9 kg de cálcio ha-1; T7: 0,1 mg L-1 de cinetina + 10 kg de nitrogênio e 9 kg de cálcio ha-1; T8: 0,2 mg L-1 de cinetina + 10 kg de nitrogênio e 9 kg de cálcio ha-1 e T9: 0,045 mg L-1 de cinetina, 0,025mg L-1 de ácido giberélico e 0,025 mg L-1 de ácido indolilbutírico + 2,45 g L-1 de cianamida hidrogenada + 10 kg de nitrogênio e 9 kg de cálcio ha-1. Para caracterização dos cachos foram avaliados a massa, comprimento e largura média dos cachos; massa, comprimento e diâmetro médio das bagas; massa seca dos engaços; número médio de bagas/cacho; número médio de cachos/planta; produtividade média/planta; sólidos solúveis, acidez titulável e ratio. Os tratamentos considerados foram 2,5; 20 e 20 mg L-1 de ácido giberélico em pó; 0,019; 0,25; 0,038; 0,5; 0,076; 1,0 mL L-1 de ácido giberélico líquido; 0,01; 0,05, 0,075; 0,1, 0,5% de cinetina, ácido giberélico e ácido indolilbutírico, respectivamente e 1,5; 3,0; 6,0; 20,0; 40,0; 80,0 mL L-1 de... / The trial was carried out in the farm Cooperyama – Juazeiro-BA, with the objective to study the efficiency of plant growth regulators on sprouting and on the cluster characteristics of ‘Itália’ grapes. To evaluate the bud sprouting, observations were done on alternate days and the number of sprouts were registered. The treatments considered were: T1: Control; T2: 2,45 g L-1of the hydrogen cyanamide ; T3: 0,045 mg L-1of kinetin, 0,025 mg L-1 of gibberellic acid the 0,025 mg L-1of indolilbutiric acid; T4: 0,09 mg L-1 of kinetin, 0,05 mg L-1 of gibberellic acid the 0,05 mg L-1 of indolilbutiric acid; T5: 0,045 mg L-1 of kinetin, 0,025 mg L-1 of gibberellic acid the 0,025 mg L-1 of indolilbutiric acid 0,045 mg L-1 of kinetin, 0,025 mg L-1 of gibberellic acid the 0,025 mg L-1 of indolilbutiric acid + 10 kg the nitrogen e 9 kg the calcium ha-1; T6: 0,09 mg L-1 of kinetin, 0,05 mg L-1 of gibberellic acid the 0,05 mg L-1 of indolilbutiric acid + 10 kg the nitrogen e 9 kg the calcium ha-1; T7: 0,1 mg L-1 of kinetin + 10 kg the nitrogen e 9 kg the calcium ha-1; T8: 0,2 mg L-1 of kinetin + 10 kg the nitrogen e 9 kg the calcium ha-1 e T9: 0,045 mg L-1of kinetin, 0,025 mg L-1 of gibberellic acid the 0,025 mg L-1 of indolbutiric acid + 2,45 g L-1of the hydrogen cyanamide + 10 kg the nitrogen e 9 kg the calcium ha-1. For cluster characterization, weight, length and average width of clusters; weight, length and average diameter of berries; dry weight of rachis; average number of berries/cluster; average number of clusters/plant; average productivity/plant; soluble solids content; acidity and ratio were evaluated. The treatments considered were 2.5; 20 and 20 mg L -1 of gibberellic acid; 0.019; 0.25; 0.038; 0.5; 0.076; 1.0 mL L-1 of gibberellic acid liquid of 0.01; 0.05, 0.075; 0.1, 0.5 % of kinetin, gibberellic acid the indolilbutiric acid, respectivemant and 1.5; 3.0; 6.0; 20.0; ...(Complete abstract click electronic access below)

La protection des vignes contre les maladies cryptogamiques telles que le mildiou est assurée majoritairement par des fongicides de synthèse dont certains posent des problèmes environnementaux et sanitaires. L’induction de résistance de la vigne par des éliciteurs des réactions de défenses pourrait permettre de réduire leur utilisation. Toutefois, l’efficacité de cette stratégie est avérée en conditions de serres, mais reste plus variable au vignoble. L’efficacité des éliciteurs est conditionnée par le niveau de réponse défensif de la plante, et plus globalement, par son état physiologique. Dans ce contexte et dans le cadre de ce travail intégré au projet FUI IRIS+, l’objectif était de vérifier si des biostimulants, via leurs effets sur la physiologie de la plante, étaient susceptibles d’augmenter son niveau de réponse aux éliciteurs. Ce projet impliquait en amont le criblage d’éliciteurs et de biostimulants efficaces sur vigne. L’activation des défenses par des éliciteurs a un coût métabolique et énergétique que la plante doit assumer. Dans un premier temps, nous avons utilisé le modèle « suspensions cellulaires » afin de comparer l’impact de deux éliciteurs oligosaccharidiques sur le métabolisme primaire de la vigne. Des analyses enzymatiques et métaboliques ont permis de montrer que l’oligogalacturonide, qui a eu la plus forte capacité à activer le métabolisme secondaire associé à la défense, comparé à la laminarine, est également celui qui a eu l’impact le plus marqué sur le métabolisme primaire ; notamment sur certains glucides et acides aminés. Ainsi, l’élicitation mobilise des ressources, impacte le métabolisme primaire de la vigne et son efficacité pourrait être conditionnée par l’état physiologique global de la plante. Dans un second temps, un criblage a été réalisé afin d’identifier de nouveaux éliciteurs potentiels parmi sept fournis par le partenaire industriel. Des tests de protection contre Plasmopara viticola (agent du mildiou) réalisés sur boutures herbacées en conditions de serres, ont permis de retenir un extrait de plante codé SDN3. Les autres ont été écartés car déjà utilisés en laboratoire (l’un d’entre eux), insuffisants en terme d’efficacité, instables ou phytotoxiques. Des études in vitro et in planta ont révélé que l’activité biologique de SDN3 est liée à deux modes d’action : par activation des défenses et par effet direct contre l’agent pathogène. Dans un troisième temps, un criblage de cinq biostimulants potentiellement efficaces sur vigne était à réaliser mais aucune méthodologie de test n’était disponible au laboratoire. Ainsi, quatre dispositifs de complexités différentes ont dû être mis au point, permettant le suivi phénotypique des parties aériennes et/ou racinaires (et dans certains cas physiologique) : systèmes « godets », « rhizotron plan », « tubes » et un autre système appelé « X » (non décrit car lié à une protection industrielle). Seuls deux modèles ont montré un intérêt. En effet, le modèle « tube » a permis de montrer une augmentation du poids frais moyen par racine primaire en réponse à un apport par la voie racinaire de l’un des produits testés, codé BS3. Le modèle « X » a également mis en évidence une accélération de l’ouverture du bourgeon, et une augmentation du nombre de racines primaires en réponse à BS3 appliqué par voie racinaire. La mise au point d’applications d’éliciteurs et d’infection par P. viticola est en cours de finalisation afin de vérifier l’hypothèse de départ à l’aide de la combinaison de BS3 avec SDN3. / The protection of vineyards against cryptogamic diseases such as downy mildew is mainly ensured by synthetic fungicides, which cause serious environmental and health problems. The induction of resistance by elicitors could allow to reduce their use. However, even if their efficacy is demonstrated in greenhouse conditions, it remains quite variable in field conditions. Indeed, the efficacy of an elicitor depends on the plant’s ability to respond, or more generally, on the latter’s physiological status. In this context, part of the FUI project IRIS+, the aim of this present work is to evaluate whether biostimulants, through their effect on the plant’s physiology, would be able to increase their responsiveness to elicitors. The activation of defenses implies a metabolic and energetic cost that the plant must get in charge. First of all, we used a cell suspension model in order to compare two oligosaccharidic elicitors on the primary metabolism of grapevine. Enzymatic and metabolic analyses showed that the oligogalacturonide, which had a stronger impact on secondary metabolism related to defense, compared to laminarin, also showed a more notable impact on primary metabolism, particularly on some sugars and amino acids. The elicitation of grapevine defenses effectively turned out to require resources. Secondly, a screening was carried out to select the most effective elicitor among seven products that were provided by the company. Protection assays against Plasmopara viticola on herbaceous cuttings allowed us to identity SDN3 as the most interesting candidate. In vitro and in planta studies revealed that the mode of action of SDN3 relied on both the activation of defenses and a direct effect against the pathogen. Lastly, as no protocol, nor methodology were available in our laboratory to screen biostimulants, four systems were developed, in order to monitor phenotypic traits of aerial and/or root system: the “pot” model, the “rhizotron” model, the “tubes”, and another termed “X” (no description allowed because of an industrial protection). Only the “X” model showed potential interests, since it allowed to display biostimulating effects such as the acceleration of the bud opening, and the increase of the mean number of primary roots, in response to BS3, applied to the roots. The development of the protocol to apply the elicitor and to infect with P. viticola spores are currently in progress, in order to assess the initial hypothesis by using the combination of BS3 and SDN3.

O cultivo de plantas das espécies de Vitis (Vitaceae), conhecidas popularmente como videiras, representa uma das atividades econômicas mais proeminentes no Sul do Brasil. Figuram entre as espécies mais ricas em compostos polifenólicos, sendo os mesmos responsáveis por inúmeras atividades biológicas e farmacológicas importantes, dentre as quais, a antioxidante. Neste contexto, este trabalho objetivou analisar quali e quantitativamente os principais grupos polifenólicos encontrados em extratos de videiras, os antocianos e flavonóides, bem como realizar ensaio para avaliação da atividade antioxidante in vitro. Neste sentido foram desenvolvidos e validados dois métodos por cromatografia líquida de alta eficiência, com detector UV/VIS. A análise dos compostos fenólicos incluíram a utilização de duas colunas diferentes, sendo uma constituída por sílica C18 e outra RP-18 com partículas híbridas contendo ligações etano-silicone. Em ambos os métodos foram utilizados sistema de eluição em gradiente, cuja composição das fases móveis foram água e acetonitrila acificadas com ácido trifluoracético. Os métodos desenvolvidos foram validados segundo as normas vigentes e atenderam aos parâmetros de validação como especificidade, linearidade, precisão, sensibilidade, exatidão e robustez nas faixas de concentração avaliadas. O presente estudo também investigou a atividade antioxidante in vitro dos extratos de videira através do método potencial antioxidante reativo total (TRAP), o qual foi otimizado e validado segundo normas internacionais, utilizando Trolox como referência. A partir deste método também foi possível avaliar a reatividade total antioxidante (TAR). Todas as concentrações testadas apresentaram reatividade instantânea inferior ao composto de referência, entretanto, demonstraram atividade antioxidante superior ao Trolox 200 nM. / The cultivation of plants from Vitis species (Vitaceae), popularly known as grapevine, is one of the most prominent economic activities in southern Brazil. The Vitis species is one of the plants that is most rich in polyphenolic compounds, responsible for numerous important pharmacological and biological activities, such as antioxidant activity. In this context, this study aimed to analyze qualitatively and quantitatively the principal groups encountered in grapevine extracts, the anthocyans and flavonoids, and to assay their antioxidant activities in vitro. For this purpose, two methods were developed and validated using high-performance liquid chromatography, employing a UV/VIS detector. The analysis of phenolic compounds included the utilization of two different columns: a column constituted by silica C18 and other RP18 column with bridged ethane-silicon hybrid particles. In both methods, a gradient system was used, with water and acetonitrile acidified with trifluoroacetic acid as a mobile phase. The methods developed were validated according to ICH evaluating parameters such as specificity, linearity, precision, sensibility, accuracy and robustness in the concentration range evaluated. The present study also analyzed the antioxidant activity in vitro of grapevine extracts employing the Total Reactive Antioxidant Potencial (TRAP) method, which was optimized and validated according to international patterns, using Trolox as a reference substance. This method also allowed evaluation of the total instantaneous reactivity (TAR). In all concentrations, the samples presented lower instantaneous reactivity than that of the reference compound. In contrast, the samples presented higher antioxidant activity than Trolox 200 nM.

La modélisation dynamique du développement de la vigne offre de nombreuses possibilités pour évaluer la pertinence des pratiques culturales pour répondre à des objectifs de production. Le développement de la vigne résulte de l’effet de différents facteurs, environnementaux, génotypiques et techniques lorsqu’elle est cultivée. Une des principales variables endogènes, résultant des effets combinés de ces trois facteurs et qui détermine en grande partie la plasticité phénotypique est la compétition trophique entre les organes. Le développement des organes peut-être décomposé en trois processus, l’initiation (organogenèse), l’expansion (morphogenèse), et la croissance en biomasse. Pour la vigne, l’organogenèse des axes est le processus de développement présentant la plus grande plasticité. Ce travail établit les bases pour la construction d’un modèle prédictif, permettant de simuler le développement de plantes de vignes soumises à une gamme de pratiques culturales et dans des environnements contrastés. Notre travail combine deux approches de modélisation, écophysiologique et mathématique. L’originalité de ce travail a été d’utiliser les deux approches de façon conjointe pour tirer parti des outils et des concepts de chacune et pour combler leurs lacunes respectives dans un objectif de modélisation des interactions plante-environnement. Le modèle GreenLab et les outils d’optimisation qui lui sont associés ont permis de quantifier précisément les relations sources-puits entre les organes et le niveau de compétition trophique qui en résulte à l’échelle de la plante. L’approche écophysiologique a permis d’établir de nouveaux formalismes de la réponse des processus d’organogénèse aux contraintes environnementales, et de les implémenter dans le modèle GreenLab. Un simulateur stochastique du développement de la vigne dans des environnements variés (thermiques, hydriques, lumineux) a ainsi pu être développé. / Dynamic models of grapevine development appear as promising tools to evaluate the relevance of training systems in order to improve both quality and quantity of production. Grapevine development is driven by different factors such as environment, genotype, and agronomic practices. The phenotypic plasticity is mainly controlled by an endogenous trait, the trophic competition between organs, which is determined by the other different factors. The development of the organs can be decomposed in three processes, the iniation (organogenesis), the expansion (morphogenesis) and the biomass growth. For grapevine, axis organogenesis was observed appear as the most plastic process. This study is a first step towards a predictive model, allowing to simulate the effects of different training systems and of contrasted environmental conditions on grapevine development. This work combines approaches based on ecophysiology and on mathematical modelling. The originality of this work was to use these two approaches together to take advantage of tools and concepts of both, and to fill in their respective deficiencies in order to model plant-environment interactions. GreenLab model and its associated optimization tools allowed to quantify precisely the source-sink relationships between organs and the trophic competition at the plant scale. The ecophysiological approach aims to input in GreenLab model new formalisms of grapevine organogenesis response to environmental constraints. In this way, a stochastic simulator of grapevine development in contrasted environments (temperature, water deficit, irradiance level) was built.

O cultivo de plantas das espécies de Vitis (Vitaceae), conhecidas popularmente como videiras, representa uma das atividades econômicas mais proeminentes no Sul do Brasil. Figuram entre as espécies mais ricas em compostos polifenólicos, sendo os mesmos responsáveis por inúmeras atividades biológicas e farmacológicas importantes, dentre as quais, a antioxidante. Neste contexto, este trabalho objetivou analisar quali e quantitativamente os principais grupos polifenólicos encontrados em extratos de videiras, os antocianos e flavonóides, bem como realizar ensaio para avaliação da atividade antioxidante in vitro. Neste sentido foram desenvolvidos e validados dois métodos por cromatografia líquida de alta eficiência, com detector UV/VIS. A análise dos compostos fenólicos incluíram a utilização de duas colunas diferentes, sendo uma constituída por sílica C18 e outra RP-18 com partículas híbridas contendo ligações etano-silicone. Em ambos os métodos foram utilizados sistema de eluição em gradiente, cuja composição das fases móveis foram água e acetonitrila acificadas com ácido trifluoracético. Os métodos desenvolvidos foram validados segundo as normas vigentes e atenderam aos parâmetros de validação como especificidade, linearidade, precisão, sensibilidade, exatidão e robustez nas faixas de concentração avaliadas. O presente estudo também investigou a atividade antioxidante in vitro dos extratos de videira através do método potencial antioxidante reativo total (TRAP), o qual foi otimizado e validado segundo normas internacionais, utilizando Trolox como referência. A partir deste método também foi possível avaliar a reatividade total antioxidante (TAR). Todas as concentrações testadas apresentaram reatividade instantânea inferior ao composto de referência, entretanto, demonstraram atividade antioxidante superior ao Trolox 200 nM. / The cultivation of plants from Vitis species (Vitaceae), popularly known as grapevine, is one of the most prominent economic activities in southern Brazil. The Vitis species is one of the plants that is most rich in polyphenolic compounds, responsible for numerous important pharmacological and biological activities, such as antioxidant activity. In this context, this study aimed to analyze qualitatively and quantitatively the principal groups encountered in grapevine extracts, the anthocyans and flavonoids, and to assay their antioxidant activities in vitro. For this purpose, two methods were developed and validated using high-performance liquid chromatography, employing a UV/VIS detector. The analysis of phenolic compounds included the utilization of two different columns: a column constituted by silica C18 and other RP18 column with bridged ethane-silicon hybrid particles. In both methods, a gradient system was used, with water and acetonitrile acidified with trifluoroacetic acid as a mobile phase. The methods developed were validated according to ICH evaluating parameters such as specificity, linearity, precision, sensibility, accuracy and robustness in the concentration range evaluated. The present study also analyzed the antioxidant activity in vitro of grapevine extracts employing the Total Reactive Antioxidant Potencial (TRAP) method, which was optimized and validated according to international patterns, using Trolox as a reference substance. This method also allowed evaluation of the total instantaneous reactivity (TAR). In all concentrations, the samples presented lower instantaneous reactivity than that of the reference compound. In contrast, the samples presented higher antioxidant activity than Trolox 200 nM.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-11-28T13:39:39Z No. of bitstreams: 1 Monique Bezerra Nascimento.pdf: 1822147 bytes, checksum: 8f2d6b8a88935d10d34decf26f6730b3 (MD5) / Made available in DSpace on 2016-11-28T13:39:39Z (GMT). No. of bitstreams: 1 Monique Bezerra Nascimento.pdf: 1822147 bytes, checksum: 8f2d6b8a88935d10d34decf26f6730b3 (MD5) Previous issue date: 2015-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The grapevine (Vitis spp.) virus diseases affect severely the production, the quality of the grape and reduce the life of the vineyards. In Brazil, among them, the complexes of rugose wood caused by Grapevine virus A (GVA), Grapevine virus B (GVB) and Grapevine virus D (GVD) and the leafroll, caused by Grapevine rupestris stem pitting-associated virus (GRSPaV) and Grapevine leafroll-associated virus -1 to -4, -4 strain 5 (GLRaV-1 to -4, -4 strain 5) are very important. The first part of the present work had the objectives of evaluating the effects of these viruses on agronomic traits, such as, fresh weight of the bunch, °Brix, weight of pruned branches, stem diameters of rootstock and canopy, in symptomatic and asymptomatic plants in Niagara Rosada and Merlot vineyards, and to survey commercial nurseries for GRSPaV, GVA, GVB, Grapevine fleck virus (GFkV) and GLRaV-3. All plants were indexed by real-time RT-PCR. Asymptomatic infected grapevines, however, were affected negatively by the viral infection, but to a lesser intensity in comparison with the symptomatic ones. The nurseries presented a high incidence of GRSPaV and GVA, being characterized as sources of inoculum for vineyards formed with these materials. The second part of the work aimed the molecular characterization of isolates of the following viruses: Prunus necrotic ringspot virus (PNRSV), agent of rose mosaic (Rosa sp.), obtained from rose; GRSPaV, GVA and GLRaV-2, from symptomatic and asymptomatic grapevine plants. Despite the economic importance of PNRSV for stone fruit trees in Brazil, only peach isolates have been molecular characterized in Brazil, it was observed high percentages of identity, among the isolates GRSPaV, GVA and GLRaV-2, which made it difficult to explain the variation in symptom expression or their absence, based on the sequence differences. In this study, it was conducted, for the first time, the molecular characterization of the complete genes to the coat protein (CP) and movement protein (MP) of a Brazilian PNRSV isolate obtained from rose. The obtained results demonstrated the high importance of using virus-free propagative materials to achieve the highest agronomic potential of the grapevine cultivars and to reduce losses caused by these pathogens. / As viroses da videira (Vitis spp.) afetam severamente a produção, a qualidade da uva e diminuem a vida útil dos vinhedos. No Brasil, destacam-se, o complexo do lenho rugoso, causados por Grapevine virus A (GVA), Grapevine virus B (GVB) e Grapevine virus D (GVD), e o enrolamento das folhas, causado por Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine leafroll-associated virus -1 ao -4, -4 estirpe 5 (GLRaV-1 ao -4, -4 estirpe 5). A primeira parte do presente trabalho teve como objetivos avaliar os efeitos destes vírus sobre as variáveis agronômicas relacionadas ao vigor da planta, tais como, peso fresco do cacho, °Brix, peso de ramos podados, diâmetros do tronco do porta-enxerto e da copa, em plantas sintomáticas e assintomáticas em vinhedos das cultivares Niágara Rosada e Merlot, além do levantamento de vírus em matrizeiros comerciais para GRSPaV, GVA, GVB, Grapevine fleck virus (GFkV) e GLRaV-3. Todas as plantas foram indexadas por RT-PCR em tempo real. Videiras assintomáticas, porém infectadas, foram afetadas negativamente pela infecção viral, porém em menor intensidade, quando comparadas com as sintomáticas. Os matrizeiros testados apresentaram alta incidência de GRSPaV e GVA, ficando caracterizados como fontes de inóculo destes patógenos para vinhedos formados com esses materiais. Na segunda parte do trabalho, visou-se a caracterização molecular de isolados dos seguintes vírus: Prunus necrotic ringspot virus (PNRSV), agente do mosaico da roseira (Rosa sp.), obtido da roseira; GRSPaV, GVA e GLRaV-2, de videiras sintomáticas e assintomáticas. Apesar da importância econômica do PNRSV para as fruteiras de caroço no Brasil, apenas isolados brasileiros, obtidos de pessegueiro, tinham sido caracterizados molecularmente. Dentro de cada espécie, os isolados de GRSPaV, GVA e GLRaV-2 demonstraram altas porcentagens de identidade, de modo que, as diferenças entre eles, dificilmente, explicariam as variações na expressão e ausência de sintomas. Neste estudo, foi realizada pela primeira vez a caracterização molecular dos genes completos da capa proteica (CP) e da proteína de movimento (MP) de um isolado brasileiro do PNRSV, obtido em roseira no Brasil. Os resultados obtidos demonstraram a utilização de material propagativo livre de vírus como opção para atingir o melhor potencial agronômico das cultivares de videira e reduzir perdas ocasionadas por estes patógenos.