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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Evaluation of Nitrogen Management Schemes in Cover Cropped Vineyards

Moss, James Russell 06 June 2016 (has links)
Vineyards in the Eastern United States are often prone to excessive vegetative growth. In order to suppress excessive vine vigor, many viticulturists have employed cover cropping strategies. Cover crops provide a myriad of agronomic benefits, however they are known to compete with the vine for water and nutrients. Due to the widespread use of cover crops in Eastern vineyards, many vineyards experience nitrogen (N) deficiencies in both the vegetative vine tissue and yeast assimilable nitrogen (YAN) in the juice. Soil applications of calcium nitrate and foliar applications of urea were assessed as a means of vineyard N amelioration at cover cropped sites comprised of Petit Manseng and Sauvignon blanc (Vitis vinifera L.). Perennial White and Crimson clover cover crops and foliar urea applications were also used in a Vidal blanc (Vitis spp.) vineyard. Treatments were imposed in the Sauvignon blanc vineyard for five years. The Petit Manseng and Vidal blanc vineyards were subjected to treatments for two years. Soil-applied N at bloom was most effective at increasing leaf petiole N at véraison, season-long chlorophyll content index (CCI), vine capacity and fruit yield. Fruit yield was increased due to more berries per cluster and greater berry weights. Increased rates of soil-applied N decreased the fruit weight:pruning weight ratio. Foliar-applied N after fruit set was most effective at increasing berry YAN. While most of the measured amino acids in fruit increased in concentration with the application of either soil or foliar N, foliar applications were more effective at increasing fruit amino acids. Clover cover crops offered little to no benefit as a N source in the two-year period of evaluation. None of the N management schemes negatively impacted canopy density, fruit zone light interception, or botrytis bunch rot incidence. The combination of both a soil-applied and foliar-applied N fertilizer may be the most effective means to increase both vine capacity and YAN in vineyards where vineyard floor cover crops are compromising vine N status. / Master of Science
172

Evaluation of Peanut Skin Extract, Grape Seed Extract, and Grape Seed Extract Fractions to Reduce Populations of Select Foodborne Pathogens

Levy, Jason M. 10 June 2014 (has links)
Grape seed extract (GSE) and peanut skin extract (PSE) are waste products in the wine and peanut industries. Both extracts have high concentrations of polyphenols, known to possess antioxidant and antimicrobial properties. A subcategory of polyphenol is procyanidin, which can be divided into two types, type A and type B. Type A (PSE), contains two single bonds connecting the phenolic groups while type B (GSE), contains one single bond connecting the phenolic groups. The minimum inhibitory concentration (MIC) of the two extracts was evaluated for their antimicrobial effect on Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella Typhimurium using the pour plate method. GSE was found to have a significantly lower MIC (p ≤ 0.05) than PSE for L. monocytogenes (GSE=60.60ppm, PSE=not found), S. aureus (GSE=38.63ppm, PSE=51.36ppm), and S. Typhimurium (GSE=45.73ppm, PSE=60.60ppm). There was no significant difference in inhibition of E. coli O157:H7 (GSE=47.44ppm, PSE=51.13ppm). Since GSE, contributed to greater pathogen inhibition, its extract was fractionated into monomer and oligomers components. Growth curves of all four pathogens inoculated in the monomer and oligomer fractions were compared using the BioScreen method. Oligomers inhibited growth of L. monocytogenes, S. aureus, and E. coli O157:H7 while monomers inhibited growth of S. Typhimurium. These results indicate that an extract with type B procyanidins that are high in oligomers may be more effective as antimicrobials. Type B procyanidins have also been shown to prevent bacterial adhesion, as is the case with urinary tract infections, and may aid in the prevention of biofilms. / Master of Science in Life Sciences
173

Optimizing nitrogen fertilization practices under intensive vineyard cover cropping floor management systems

D'Attilio, DeAnna Rae 28 March 2014 (has links)
Under-trellis cover crops have become more prevalent in East Coast grape growing regions through either intentional planting or adoption of native vegetation, to minimize the potential for erosion and to help regulate grapevine size and vigor. These companion crops, however, have sometimes resulted in increased competition for soil nitrogen, leading to decreased vine nitrogen status and berry yeast assimilable nitrogen (YAN). The aim of this study was to determine the effects of different nitrogen fertilization methods applied at varying doses and different times, on vine and berry nitrogen parameters of cover cropped grapevines. The research described herein involved Sauvignon blanc, Merlot, and Petit Manseng grapevines (Vitis vinifera L.) subjected to different sets of nitrogen treatments, and was primarily conducted over two years. There were very few differences in pruning weights, canopy architecture, components of yield, and primary fruit chemistry amongst nitrogen treatments. Sauvignon blanc petiole nitrogen concentration, season-long chlorophyll content index (CCI) values, and berry YAN were most affected by the highest rate of soil nitrogen treatment (60 kg N/ha total split between two calcium nitrate applications at bloom and six weeks post bloom) and foliar fertilization (40 kg N/ha split over seven to nine urea applications); however, the foliar fertilization was most effective at increasing the concentration of certain individual amino acids. Petit Manseng berry YAN at harvest was increased in response to post-véraison foliar applications (10 kg N/ha split between two urea applications), corresponding to an increased concentration of nine amino acids. Merlot berry YAN, petiole nitrogen concentration, and season-long CCI values were most affected by a high rate of soil nitrogen treatment (60 kg N/ha total split between two calcium nitrate applications at bloom and six weeks post bloom) and establishing clover as the under-trellis cover crop. This study identified nitrogen treatments that improved berry nitrogen concentration and content in cover cropped sites. / Master of Science
174

Isolation and characterization of antifungal peptides from plants

De Beer, Abre 03 1900 (has links)
Thesis (PhD (Viticulture and Oenlogy))--University of Stellenbosch, 2008. / Includes bibliography and list of tables and figures. / ENGLISH ABSTRACT: Over the last decade research has shown the importance of small antimicrobial peptides in the innate immunity of plants. These peptides do not only play a critical role in the multilayered defense systems of plants, but have proven valuable in the engineering of disease resistant food crops towards the ultimate aim of reducing the dependency on chemical fungicides. As the lists of isolated and characterized peptides grew, it became clear that other biological activities, in addition to the antimicrobial capacity, could be linked to some of these peptides; these alternative activities could have important applications in the field of medicine. This has made the defensin encoding genes prime targets for the agricultural and medical biotechnology sectors. To this end we set out to evaluate South African flora for the presence of plant defensin sequences and to isolate plant defensin genes that might be useful in biotechnology applications. Moreover, by isolating and characterizing these novel peptides, also in an in planta environment and in interaction with fungal pathogens, important knowledge will be gained of the biological role and importance of the peptides in the plant body. The plant host targets were South Africa Brassicaceae species including indigenous species, as well as Vitis vinifera, as the most important fruit crop in the world and since no defensins have been isolated from this economically important crop plant. The Brassicaceae family has been shown to be abundant in defensin peptides and several of the best characterized peptides with potent activity have been isolated from this family. Based on initial activity screens conducted on selected South African Brassicaceae spp. we concluded that these spp. contain promising antifungal peptide activities, warranting further efforts to isolate the genes and encoding peptides and to characterize them further. The preliminary activity screens used a peptide-enrichment isolation strategy that favored the isolation of basic, heat-stable peptides; these properties are characteristic features of plant antimicrobial peptides. These peptide fractions showed strong antifungal activities against the test organisms. A PCR-amplification strategy was subsequently designed and implemented, leading to the isolation of 14 novel defensin peptide encoding genes from four South African Brassicaceae spp., including the indigenous South African species Heliophila coronopifolia. Amino acid sequence analysis of these peptides revealed that they are diverse in amino acid composition and share only 42% homology at amino acid level. This divergence in amino acid composition is important for the identification of new biological activities within closely related plant defensins. Single amino acid changes have been contributed with the divergent biological activities observed in closely related plant defensin peptides. Phylogenetic analysis conducted on the deduced amino acid sequences revealed that all the new defensins share a close relationship to other Brassicaceae members of the plant defensin superfamily and was furthest removed from the defensins isolated from the families Solanaceae and Poaceae. Classification analysis of these peptides showed that they belong to subgroup A3 of the defensin superfamily. A putative defensin sequence was also isolated from V. vinifera cultivar, Pinotage, and termed Vv-AMP1. Genetic characterization showed that only a single gene copy of this peptide is present within the V. vinifera genome, situated on chromosome 1. Genetic characterization of this peptide encoding gene within the Vitis genus showed that this gene has stayed conserved throughout the divergent evolution of the Vitis genus. Expression studies of Vv-AMP1 revealed that this gene is expressed in a tissue specific and developmentally regulated manner, being only expressed in grape berries and only at the onset of vèraison. Induction of Vv-AMP1 in grapevine leaf material could never be achieved through the external application of hormones, osmotic stress, wounding, or pathogen infection by Botrytis cinerea. Deduced amino acid analysis showed that Vv-AMP1 encoded for a 77 amino acid peptide consisting of a 30 amino acid signal peptide and a 47 amino acid mature peptide, with putative antifungal activity. The Vv-AMP1 peptide grouped with the subclass B type defensins, which have been documented to have both antifungal and antibacterial activities. The Vv-AMP1 signal peptide directed the green fluorescent protein (GFP) reporter gene to the apoplastic regions in cells with high levels of accumulation in the vascular tissue and the guard cells of the stomata. Recombinant Vv-AMP1 peptide was successfully purified from a bacterial host and shown to have a size of 5.495 kDa. Recombinant Vv-AMP1 showed strong antifungal activity at low concentrations against a broad spectrum of fungal pathogens, which included Verticillium dahliae (IC50 of 1.8 μg mL-1) and the necrotrophic pathogen Botrytis cinerea (IC50 of 12-13 μg mL-1). Antifungal activity of Vv-AMP1 did not induce morphological changes in fungal hyphae, but its activity was associated with induced membrane permeabilization in treated hyphae. Vv-AMP1 was successfully introduced into Nicotiana tabacum as confirmed by Southern blot analysis and 20 individual lines were generated. Genetic characterization confirmed the integration and expression of the gene in the heterologous tobacco environment. The peptide was under control of its native signal sequence which has been shown to direct its product to the apoplastic regions of cells. The transgenic lines were analyzed to determine the presence and activity of the grapevine defensin peptide. Western blot analyses of partially purified plant extracts detected a signal of the expected size in both the untransformed control and the transgenic lines. Comprehensive analysis of EST databases identified three highly homologous sequences from tobacco that probably caused the background signal in the control. These crude protein extracts were able to inhibit the growth of V. dahliae in vitro when tested in a microtiter plate assay, but the inhibition could not be conclusively linked to the presence of the transgenic peptide, since non-expressing transgenic lines, included as controls, also showed inhibition. Similar results were obtained with infection studies, clearly showing that despite successful integration and expression of the transgene, the peptides was either not functional in the heterologous environment, or perhaps unstable under the particular regulatory conditions. This peptide belongs to a subclass of peptides known for associated activities that might activate tight control by plant hosts if threshold levels are reached. These aspects need further investigation, specifically since it is in stark contrast to previous results obtained with defensins from a different subclass. This study has also yielded significant other related resources that would be instrumental for further possible biotechnology exploitation of some of the novel peptides, but also to provide genetic constructs and plant material that would be invaluable to address fundamentally important questions such as the regulation and mode of action of defensin peptides, specifically in interaction with pathogen hosts. The novel peptides have been transformed to various hosts, including grapevine and these transgenic populations are available to facilitate the next rounds of research into this extremely promising group of antifungal peptides. / AFRIKAANSE OPSOMMING: In die laaste dekade het navorsing die belangrike rol van klein antimikrobiese peptiede in plantweerstandsmeganismes beklemtoon. Hierdie peptiede speel nie alleenlik 'n belangrike rol in die komplekse lae van plantweerstandstelsels nie, maar het ook hulle ekonomiese potensiaal getoon in die manipulering van siekteweerstandbiedendheid in voedselgewasse met die oorkoepelende doel om landbougewasse minder afhanklik van chemiese spuitstowwe te maak. Soos wat die hoeveelheid geïsoleerde en gekarakteriseerde peptiede toeneem, het dit duidelik geword dat ander biologiese aktiwiteite, bykomend tot die antimikrobiese kapasiteit, met sommige van dié peptiede verbind kan word; hierdie alternatiewe aktiwiteite het belangrike toepassing in veral die mediese veld. Dit het die defensin-koderende gene kernteikens vir die landbou- en mediese biotegnologiesektore gemaak. In die studie is daar begin om die Suid-Afrikaanse blommeryk te evalueer vir die teenwoordigheid van plantdefensingene en om dié gene te isoleer wat van ekonomiese belang vir die biotegnologiebedryf kan wees. Deur die in vitro- én in planta karakterisering van die unieke plantdefensinpeptiede word daar gemik daarna om belangrike inligting in te win oor die biologiese rol van die peptiede binne die plantligggaam. Die plantgashere wat geteiken is sluit in die Suid-Afrikaanse Brassicaceae-spesies, insluitende inheemse spesies, asook Vitis vinifera, wat as die belangrikste vrugtegewas ter wêreld beskou word. Die Brassicaceae-familie is welbekend daarvoor dat dit 'n ryk bron van plantdefensinpeptiede is en verskeie van die bes gekarakteriseerde antifungiese defensinpeptiede is van dié familie afkomstig. Aanvanklike aktiwiteitstoetse het getoon dat die Suid-Afrikaanse Brassicaceae-spesies belowende antifungiese aktiwiteit toon, wat die verdere isolering en karakterisering van dié gene en hul peptiedprodukte regverdig. Die aanvanklike aktiwiteitstoetse het 'n selektiewe peptiedverrykingstrategie gevolg wat die isolering van basiese, hittestabiele peptiede bevoordeel het; hierdie eienskappe is baie kenmerkend van plant-antimikrobiese peptiede. Die peptiedfraksies wat met hierdie metode geïsoleer is, het sterk antifungiese aktiwiteit teen die toetsorganismes getoon. Die resultate het gelei tot die ontwikkeling en toepassing van 'n polimerasekettingreaksie-strategie, wat daartoe gelei het dat 14 nuwe defensingene van vier Suid-Afrikaanse Brassicaceae-genera, insluitend die inheemse spesie Heliophila coronopifolia, geïsoleer kon word. Afgeleide aminosuurvolgorde-analises van die nuwe defensinpeptiede het gewys dat hulle slegs 42% homologie het. Hierdie diversiteit in aminosuurvolgorde is belangrik vir die identifisering van nuwe biologiese aktiwitiete binne die groep van verwante peptiede. Navorsing het verder getoon dat enkel-aminosuurverskille bydra tot die diverse spektrum van biologiese aktiwiteite binne 'n groep van verwante defensinpeptiede. Filogenetiese analise van die aminosuurvolgordes het getoon dat al die nuwe defensinpeptiede 'n sterk verwantskap met plantdefensinpeptiede, wat van ander Brassicaceae-spesies geïsoleer is, toon. Daarteenoor het dit die kleinste verwantskap getoon met plantdefensinpeptiede wat van die Solanaceae- en Poaceae-families geïsoleer is. Klassifikasiestudies het bewys dat die nuwe peptiede saam met subgroep A3 van die plantdefensin-superfamilie groepeer. 'n Moontlike plantdefensingeen, genaamd Vv-AMP1, is ook van die V vinifera-kultivar, Pinotage, geïsoleer. Genetiese karakterisering het aangedui dat slegs 'n enkele kopie van die geen in die V. vinifera-genoom teenwoordig en op chromosoom 1 geleë is. Genetiese karakterisering van Vv-AMP1 binne die Vitus-genus het gewys dat die geen binne die genus evolusionêr gekonserveerd is. Uitdrukkingstudies van Vv-AMP1 het verder bewys dat die geen uitgedruk word op 'n weefselspesifieke, ontwikkelingsgekoppelde wyse, naamlik slegs in druiwekorrels en slegs tydens rypwording. Vv-AMP1-uitdrukking kon nooit geïnduseer word in wingerdblare deur die uitwendige toediening van hormone, osmotiese stres, wonding of patogeeninfeksie deur Botrtys cinerea nie. Ontleding van die afgeleide aminosuurvolgorde het gewys dat Vv-AMP1 kodeer vir 'n 77-aminosuurpeptied, wat uit 'n 30-aminosuurseinpeptied en 'n 47-aminosuur-aktiewe peptied met voorspelde antifungiese aktiwiteit bestaan. Die Vv-AMP1-peptied is gegroepeer met subgroep B van die plantdefensin-superfamilie, 'n subgroep wat vir beide antifungiese en antibakteriese aktiwiteit gedokumenteer is. Die Vv-AMP1-seinpeptied het die groen fluoressensie-indikatorproteïen (GFP) na die apoplastiese areas van die plantselle gelei, met hoë vlakke van lokalisering in die vaatbundelweefsel en sluitselle van die huidmondjies. Die rekombinante Vv-AMP1-peptied is suksesvol geproduseer en uit 'n bakteriese produksieras gesuiwer, en het 'n molekulêre massa van 5.495 kDa gehad. Die gesuiwerde peptide het by lae konsentrasies 'n sterk aktiwiteit getoon teen 'n breë spektrum van fungiese patogene, wat Verticllium dahliae (IC50 van 1.8 μg mL-1) en die nekrotrofiese patogeen, B. cinerea (IC50 van 12-13 μg mL-1), ingesluit het. Vv-AMP1-aktiwiteit het geen ooglopende morfologiese veranderinge in die fungi-hifes veroorsaak nie, maar hulle aktiwiteit is verbind met 'n verhoogde membraandeurdringbaarheid in behandelde fungi-hifes. Suksesvolle intergrasie van Vv-AMP1 in die Nicotiana tabacum-genoom is deur Southern-kladontledings bevestig en 20 individuele transgeniese lyne is ontwikkel. Genetiese karakterisering van die transgeniese lyne het gewys dat Vv-AMP1 suksesvol geïntegreer is en ook in die transgeniese tabakomgewing uitgedruk word. Die peptied is uitgedruk onder beheer van sy eie seinpeptied, wat die aktiewe produk na die apoplastiese areas van die plantselle teiken. Die transgeniese tabaklyne is ook ontleed om te bepaal of die wingerdpeptied suksesvol geproduseer word en sy aktiwiteit in die transgeniese omgewing behou. Western-kladanalise van semi-gesuiwerde plantproteïenekstrakte het 'n positiewe sein gelewer in beide die kontroleplante en die transgeniese plantlyne. Bestudering van tabakgeenuitdrukkings-databasisse het drie nukleotiedvolgordes opgelewer wat homologie met Vv-AMP1 toon en moontlik verantwoordelik kan wees vir die positiewe sein in die ongetransformeerde kontroleplante. Kru proteïenekstrakte van die transgeniese tabaklyne het in vitro-aktiwiteit teen V. dahliae getoon. Geen oortuigende ooreenkoms kon egter gevind word tussen V. dahliae-inhibisie en die teenwoordigheid van die transgeniese Vv-AMP1-peptied nie, aangesien kontroleplante wat Southern-klad-positief is, maar nie geenuitdrukking toon nie, ook inhibisie van V. dahliae veroorsaak het. Soortgelyke resultate is met infeksiestudies verkry. Alle resultate dui daarop dat, al is daar suksesvolle integrasie en uitdrukking van die geen in tabak verkry, dat die Vv-AMP1 peptied óf onaktief óf onstabiel in die transgeniese tabakomgewing is. Die peptied behoort aan 'n subgroep peptiede met aktiwiteite wat, sodra sekere vlakke van peptied oorskry word, die moontlik streng kontrole op proteïenvlak in die gasheerplant kan uitlok. Sekere aspekte van die studie sal verder bestudeer moet word, aangesien die data teenstrydig is met data wat verkry is met soortgelyke plantdefensinpeptiede wat aan 'n ander subgroep behoort. Die studie het baie hulpbronne gegenereer wat vir die biotegnologiesektor belangrik kan wees, veral op ekonomiese gebied. Verder is die geenkonstrukte en plantlyne wat ontwikkel is waardevol om fundamentele vrae rondom die regulering en meganisme van aksie van defensinpeptiede, spesifiek plantpatogeeninteraksie, te beantwoord. Die nuwe plantdefensingene is na verskeie gasheerplante, insluitende wingerd, getransformeer waar die transgeniese lyne die volgende rondte van navorsing oor die bestudering oor die belangrike groep van antifungiese peptiede, sal aanvul.
175

The effect of within-vineyard variability in vigour and water status on carbon discrimination in Vitis vinifera L. cv Merlot

Rossouw, Gerhard C. 03 1900 (has links)
Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Within-vineyard variability in vigour and water status commonly occurs in South African vineyards. Different soil types found over short distances are probably the main cause of vigour variability, while differences in grapevine water status are commonly induced by lateral water flow in the vineyard, blocked irrigation emitters and differences in soil water-holding capacity. These factors can cause heterogeneous ripening and differences in fruit quality between different parts of the vineyard, an aspect that needs to be avoided as far as possible in order to produce quality wines. Measurements of carbon isotope discrimination (CID) have proved to be a tool to assess grapevine physiology in order to study the effects of environmental parameters on leaf carbon dioxide (CO2) gas exchange and stomatal conductance (gs). Grapevine water deficit stress/strain in reaction to these environmental conditions can then be determined by observing the amount of 13C absorbed by plant material after discrimination of 13C has taken place, and this is influenced by the grapevine stress condition and can indicate water-use efficiency. In this study, the variability of grapevine water status and vigour was determined in order to quantify these parameters in different parts of the vineyard. Two separate trials were conducted, the first at Wellington, South Africa, where different irrigation regimes resulted in variability in grapevine water status between plots. The second trial was at Stellenbosch, South Africa, where plots were divided among different vigour classes and irrigation was applied in different quantities for different irrigation treatments. Within-vineyard variability in water status (Wellington and Stellenbosch) and vigour (Stellenbosch) were then quantified and the effects on some grapevine physiological parameters and berry composition were measured. The treatments in the Wellington trial led to differences in grapevine water status, which could be quantified by measurements of stem water potential (SWP) and leaf water potential (LWP). Soil variability also led to differences in grapevine vigour, which were quantified by measurements of pruning mass, leaf area and shoot length. The effect of the variability in grapevine water status on grapevine physiology was assessed by measuring CID, which was the main focus of the study. Other physiological measurements, such as gs and leaf and canopy temperature, were also conducted. The effect of these conditions on grape berry composition was also studied. In the Stellenbosch trial, soil water content, plant water status measurements (SWP, predawn LWP and LWP), physiological measurements (CID and gs) and berry size measurements were used to classify plots into water status treatments (“wet” and “dry” treatments). The effect of vigour differences was analysed separately from these treatments by using pruning mass as a covariate in the statistical analyses. The effect of vigour variability on the measurements was studied by looking at the effect of the covariate on the measurements, while shoot growth rate, shoot length and leaf area measurements were conducted as vegetative growth measurements. Differences in measurements were then studied between the treatments and between the vigour levels of the different plots. In the Wellington trial, plant water status was determined by irrigation, showing increased stress for treatments that received less irrigation. The differences in plant water status then caused differences in grapevine physiology between the treatments, leading to increased gs for increased irrigation. This of course influenced leaf internal CO2 and therefore CID, although CID was also clearly influenced by berry development. Berry size was influenced by irrigation, with larger berries found in wetter treatments, while berry chemical composition was influenced by the irrigation regime, with increased irrigation leading to increased pH and leading to trends showing increased total soluble solids and malic acid, and reduced total and tartaric acid and colour intensity. In the Stellenbosch trial, plots with higher vigour had increased shoot growth rate, longer shoots and increased leaf area, although topping influenced this. Wet treatment vines also showed slightly longer shoots and larger leaf areas. There were differences in soil water content between the wet and dry treatments, and this led to differences in plant water status. Vigour also influenced pre-dawn LWP, especially in the 2007 season, as higher-vigour vines struggled more to rehydrate through the night. Differences in plant water potential led to differences in grapevine physiology, with increased gs for vines from the wet treatment, while higher-vigour vines had slightly increased gs. The differences in gs led to gas exchange differences and therefore differences in CID, meaning that water status and vigour influenced CID. CID measurements illustrated the long term effect of water status on plant physiology, while measurements such as SWP illustrated the short term effects. CID measurements therefore proved to be accumulative over the season, in contrast to SWP measurements that were much more dependent on the current state of grapevine water status. Other physiological measurements showed that wet-treatment vines had higher photosynthetic rates and evapotranspiration and lower leaf temperatures, while higher-vigour vines had slightly increased evapotranspiration and decreased leaf temperatures. Wet-treatment vines had larger berries, while a higher vigour also led to slightly larger berries. Berry composition was influenced by treatment, where wet-treatment vines had increased pH and total soluble solids, while higher-vigour vines had increased juice pH and, in the 2008 season, decreased total soluble solids. Extremely stressed conditions did not show significant effects on plant water potential, but SWP measurements indicated slightly higher stress for the extremely stressed vines and LWP showed slightly less stressed conditions for these vines. Measurements of gs showed slightly lower values for the extremely stressed vines, while measurements of CID showed large significant differences, with the extremely stressed vines having measurements showing high stress. The measurement therefore indicated highly stressed conditions accurately, while other physiological measurements, such as photosynthetic rate, evapotranspiration and leaf temperatures, only showed trends and no significant differences. Measurements of stomatal conductance reacted to plant water status measurements throughout the diurnal measurement days, while CID only reacted slightly with gs changes during these days and was perhaps influenced more by berry chemical composition and development at this early stage of the season. Vigour and water status therefore influenced grapevine physiology, with a more direct effect by water status and an indirect effect by vigour due to microclimatic differences. This also influenced berry composition and therefore quality. In future studies, CID measurements should be done on juice from which organic acids have been removed in order to eliminate the effect of seasonal berry composition on the measurement. Measurements of CID proved to be an integrative, but sensitive, indicator of grapevine stress, especially at the end of the season. It might at best be useful as a post-harvest management tool for producers or grape buyers, especially for irrigation control, as has also been stated by Van Leeuwen et al. (2007). / AFRIKAANSE OPSOMMING: Binne-wingerd variasie in groeikrag en waterstatus is algemeen in Suid-Afrikaanse wingerde. Verskillende grondsoorte wat na aan mekaar voorkom, is seker een van die vernaamste oorsake van variasie in groeikrag, terwyl verskille in wingerdwaterstatus algemeen deur laterale watervloei in die wingerd, verstopte besproeiingspuite en verskille in grond waterhouvermoë geïnduseer word. Hierdie faktore kan aanleiding gee tot heterogene rypwording en verskille in vrugkwaliteit tussen verskillende dele van die wingerd, ‘n aspek wat so ver moontlik vermy moet word om kwaliteitwyne te kan produseer. Die meting van koolstof-isotoopdiskriminasie (KID) is bewys om as gereedskap te kan dien vir die assessering van wingerdfisiologie om die effekte van omgewingsparameters op blaar koolstofdioksied (CO2) - gasuitruiling en stomatale geleiding (gs) te bestudeer. Die stres/stremming as gevolg van ‘n watertekort in die wingerd in reaksie op hierdie omgewingstoestande kan dan bepaal word deur te kyk na hoeveel 13C deur die plantmateriaal geabsorbeer word ná 13C-diskriminasie plaasgevind het, en dít word deur die wingerdstrestoestande beïnvloed en kan ‘n aanduiding verskaf van die doeltreffendheid van waterverbruik. In hierdie studie is die variasie in wingerdwaterstatus en groeikrag bepaal om hierdie parameters in verskillende dele van die wingerd te kwantifiseer. Twee afsonderlike proewe is uitgevoer, die eerste by Wellington, Suid-Afrika, waar verskillende besproeiingsregimes gelei het tot verskille in die wingerdwaterstatus tussen persele. Die tweede proef was by Stellenbosch, Suid-Afrika, waar persele tussen verskillende groeikragklasse verdeel is en besproeiing in verskillende hoeveelhede vir verskillende besproeiingsbehandelings toegepas is. Binne-wingerd variasie in waterstatus (Wellington en Stellenbosch) en groeikrag (Stellenbosch) is toe gekwantifiseer en die effekte op sekere wingerd-fisiologiese parameters en korrelsamestelling is gemeet. Die behandelings in die Wellington-proef het gelei tot verskille in wingerdwaterstatus, wat deur metings van stamwaterpotensiaal (SWP) en blaarwaterpotensiaal (BWP) gekwantifiseer kon word. Grondverskille het ook gelei tot verskille in wingerdgroeikrag, wat deur metings van snoeimassa, blaaroppervlak en lootlengte gekwantifiseer is. Die effek van die variasie in wingerdwaterstatus op wingerdfisiologie is deur metings van KID bepaal wat die hooffokus van hierdie studie was. Ander fisiologiese metings, soos gs en blaar- en lowertemperatuur, is ook gedoen. Die effekte van hierdie toestande op die samestelling van die druiwekorrels is ook bestudeer. In die Stellenbosch-proef is grondwaterinhoud, metings van plantwaterstatus (SWP, voorsonopgang SWP en BWP), fisiologiese metings (KID en gs) en metings van korrelgrootte gebruik om die persele in waterstatusbehandelings (“nat” en “droë” behandelings) te verdeel. Die effek van verskille in groeikrag is apart van hierdie behandelings geanaliseer deur snoeimassa as ‘n kovariaat in die statistiese analises te gebruik. Die effek van groeikragvariasie op die metings is bestudeer deur ondersoek in te stel na die effek van die kovariaat op die metings, terwyl lootgroeitempo-, lootlengte- en blaaroppervlakmetings as metings van vegetatiewe groei uitgevoer is. Verskille in metings tussen die behandelings en tussen die groeikragvlakke van die verskillende persele is toe bestudeer. In die Wellington-proef is plantwaterstatus deur besproeiing bepaal, met verhoogde stres in behandelings waar daar minder besproeiing toegedien is. Die verskille in plantwaterstatus het dan verskille in wingerdfisiologie tussen die behandelings veroorsaak, wat gelei het tot ‘n verhoogde gs in die geval van verhoogde besproeiing. Dit het natuurlik ‘n effek op die interne CO2 van die blaar en dus op KID gehad, hoewel KID ook duidelik deur korrelontwikkeling beïnvloed is. Korrelgrootte is deur besproeiing beïnvloed, met groter korrels in die natter behandelings, terwyl die chemiese samestelling van die korrel deur besproeiingsregime beïnvloed is. Verhoogde besproeiing het pH verhoog en gelei na tendense wat verhoogde totale oplosbare vaste stowwe en appelsuur, en verminderde totale suur, wynsteensuur en kleurintensiteit getoon het. In die Stellenbosch-proef het persele met hoër groeikrag ook verhoogde lootgroeitempo, langer lote en verhoogde blaaroppervlak getoon, hoewel dit deur top beïnvloed is. Wingerdstokke van die nat behandeling het ook effe langer lote en groter blaaroppervlakke getoon. Daar was verskille in grondwaterinhoud tussen die nat en droë behandelings en dit het verskille in plantwaterstatus veroorsaak. Groeikrag is ook deur voor-sonopgang BWP beïnvloed, veral in die 2007-seisoen, aangesien stokke met hoër groeikrag meer gesukkel het om in die nag te rehidreer. Verskille in plantwaterpotensiaal het gelei tot verskille in wingerdfisiologie, met ‘n verhoogde gs vir stokke in die nat behandeling, terwyl stokke met hoër groeikrag ‘n effens verhoogde gs getoon het. Die verskille in gs het gelei tot verskille in gasuitruiling en dus verskille in KID, wat beteken dat waterstatus en groeikrag ‘n invloed op KID het. KID was meer verteenwoordigend van die langtermyneffekte van water status op plantfisiologie, terwyl metings soos SWP die korttermyneffekte weerspieël het. KID metings was dus akkumalatief oor die seisoen, terwyl SWP metings meer ‘n weerspieëling was van die huidige toestand van plantwaterpotensiaal. Ander fisiologiese metings het getoon dat stokke in die nat behandeling ‘n hoër fotosintesetempo en evapotranspirasie sowel as laer blaartemperature ondervind het, terwyl die stokke met hoër groeikrag effe verhoogde evapotranspirasie en verminderde blaartemperature getoon het. Stokke in die nat behandeling het groter korrels gehad, terwyl hoër groeikrag ook effens groter korrels veroorsaak het. Korrelsamestelling is deur die behandelings beïnvloed, met stokke in die nat behandeling wat verhoogde pH en totale oplosbare vaste stowwe getoon het, terwyl stokke met hoër groeikrag verhoogde pH van die sap en verminderde totale oplosbare vaste stowwe (laasgenoemde in die 2008-seisoen) gehad het. Uitermate toestande van stres het geen beduidende effekte op plantwaterpotensiaal getoon nie, hoewel SWP-metings effens hoër stres vir die uitermate gestresde wingerde getoon het en BWP effens minder gestresde toestande vir hierdie stokke getoon het. Metings van gs het effens laer waardes vir die uitermate gestresde stokke getoon, terwyl metings van KID groot noemenswaardige verskille getoon het, met die metings vir die uitermate gestresde wingerde wat hoër stres aangedui het. Dié meting het dus hoogs gestresde toestande akkuraat aangedui, terwyl ander fisiologiese metings, soos tempo van fotosintese, evapotranspirasie en blaartemperature net tendense en nie beduidende verskille aangedui het nie. Metings van stomatale geleiding het dwarsdeur die dae waarop daaglikse metings gedoen is op plantwaterstatusmetings gereageer, terwyl KID net effens met gs-veranderinge op hierdie dae gereageer het en moontlik meer deur die chemiese samestelling en ontwikkeling van die korrel in hierdie vroeë stadium van die seisoen beïnvloed is. Groeikrag en waterstatus het dus wingerdfisiologie beïnvloed, met ‘n meer direkte effek deur waterstatus en ‘n indirekte effek deur groeikrag as gevolg van mikroklimaatsverskille. Dit het ook korrelsamestelling en dus kwaliteit beïnvloed. In toekomstige studies moet KID-metings gedoen word op sap waarvan die organiese sure verwyder is om die effek van seisoenale korrelsamestelling op die meting uit te sluit. Metings van KID is getoon om ‘n integrerende, maar gevoelige, aanduider van wingerdstres te wees, veral aan die einde van die seisoen. Dit is ten beste miskien bruikbaar as naoesbestuursgereedskap vir produsente of druiwekopers, veral vir besproeiingsbeheer, soos ook reeds deur Van Leeuwen et al. (2007) aangedui is.
176

Limpeza clonal de videira com cancro-bacteriano e sobrevivência de Xanthomonas campestris pv. viticola em tecidos infectados

SILVA, Adriano Márcio Freire 26 February 2009 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-20T14:28:26Z No. of bitstreams: 1 Adriano Marcio Freire da Silva.pdf: 233973 bytes, checksum: 8365664074820b5955fb940c37b47616 (MD5) / Made available in DSpace on 2017-02-20T14:28:26Z (GMT). No. of bitstreams: 1 Adriano Marcio Freire da Silva.pdf: 233973 bytes, checksum: 8365664074820b5955fb940c37b47616 (MD5) Previous issue date: 2009-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Bacterial canker (Xanthomonas campestris pv. viticola) (Xcv) caused great damage to the grapevine cultivation in the Vale do Submédio São Francisco. In the first paper techniques of in vitro tissue culture in modified Galzy medium (MGM) were studied in order to eliminate Xcv from ‘Red Globe’ grapevine plants. The first experiment aimed to select the ideal length of apex and axillary’s buds for cultivation in MGM; the second to verify the effect of the thermotherapy (38ºC/four weeks) associated to the MGM cultivation; and the third intended to test antibiotics to eliminate Xcv from explants taken from infected grapevines. All plants obtained without contamination in vitro and culture media contaminated were indexed by using the semi-selective culture media nutrient agar-dextrose-yeast extract-ampicilin (NYDAM) followed by a pathogenicity test. The cultivation of 3 mm explants permitted to obtain plants free of bacteria with regeneration 14.3 times higher than 1 mm explants. The thermotherapy of infected plants associated to the in vitro culture did not eliminate the pathogen. The cultivationof 10 mm explants for 40 days in MGM+cefotaxime (300 mg L-1) eliminated Xcv from grapevine plants. The indexation in NYDAM permitted the visualization of specific Xcv growing. The indexation of in vitro regenerated grapevine plants for Xcv infection by using NYDAM medium is an economic and efficient alternative for production of selected plants. It is known that pruning residues of infected plants abandoned in the grapevine plantations are important source of disease primary inoculum and that burning is recommended as control measure. Thus the second paper investigated the survival of Xcv in infected tissues and the use of composting to eradicate Xcv associated with crop residues. Plants of grapevine “Festival’ were inoculated with a mutant resistant to rifampicin Xcv2Rif and at the time they presented high disease severity, fragmented shoots and entire leaves were placed in mesh bags. These bagswere placed on the surface of microplots in experimental area (experiment 1) and inside compost piles of grapevine pruning residues (experiment 2). The survival of Xcv2Rif in grapevine infected tissue was monitored in the culture medium NYDAM + rifampicin (0,1g L-1) + azoxystrobim (0,16 g L-1), at 8 and 10 days intervals from 1 and 2 experiment setting, respectively. In the experiment 1 tissue decomposition was also evaluated and in the experiment 2, pile temperature curves, phenolyc content, and fungi and bacteria antagonistic to Xcv2Rif were analyzed. The pathogen survived in high densities (104 a 106 CFU g-1) for at least 80 days in grapevine-infected tissues on soil surface. Then grapevine-pruning residues are important inoculum source for other plants in the vineyard. The composting process eliminated Xcv2Rif from crop residues in 10 days due to high temperatures in piles, liberation of phenolyc compounds during the process and microbial antagonism. Therefore the composting is a viable and safemethod to manage pruning residues in grapevine plantations without problems of Xcv survival and without losing of an important source of organic matter for the culture. / O cancro-bacteriano causado por Xanthomonas campestris pv. viticola (Xcv) é responsável por grandes prejuízos ao cultivo de videira no Vale do Submédio São Francisco. No primeiro trabalho, técnicas de cultura de tecidos em meio de Galzy modificado (MGM) foram estudadas visando eliminar Xcv de mudas de videira ‘Red Globe’. O primeiro experimento visou selecionar o tamanho ideal de ápices e gemas axilares para o cultivo em MGM; o segundo, verificar o efeito da termoterapia de mudas (38ºC/quatro semanas) associada ao cultivo em MGM; e o terceiro, testar antibióticos para eliminação de Xcv em explantes oriundos de videiras infectadas. Todas as plantas obtidas sem contaminação in vitro e meios de cultivo contaminados foram indexados utilizando o meio ágar nutritivo-dextrose-extrato de leveduraampicilina (NYDAM) seguindo-se teste de patogenicidade. O cultivo de explantes com 3 mm possibilitou a obtenção de plantas livres da bactéria, com regeneração 14,3 vezes maior que explantes de 1 mm de comprimento. A termoterapia de mudas infectadas associada ao cultivo in vitro não eliminou o patógeno. O cultivo de explantes com 10 mm durante 40 dias em MGM+cefotaxima (300 mg L-1) proporcionou limpeza clonal das mudas. A indexação em NYDAM permitiu a visualização do crescimento de Xcv. A indexação de plantas de videira regeneradas in vitro quanto à infecção por Xcv utilizando NYDAM é uma alternativa econômica e eficiente para produção de plantas selecionadas. Sabe-se que restos de poda de plantas infectadas deixados no parreiral são importante fonte de inóculo primário da doença, recomendando-se a queima como medida de controle. No segundo trabalho, investigou-se a sobrevivência de Xcv em tecidos de videira infectados e o uso da compostagem para erradicação de Xcv em associação com restos culturais. Mudas de videira ‘Festival’ foram inoculadas com omutante resistente a rifampicina Xcv2Rif e quando apresentavam alta severidade da doença, ramos fragmentados e folhas inteiras foram acondicionados em bolsas de malha plástica. Estas foram alocadas na superfície de microparcelas em área experimental (experimento 1) e no interior de pilhas de compostagem de restos de poda de videira (experimento 2). A sobrevivência de Xcv2Rif em tecidos infectados de videira foi monitorada em meio NYDAM + rifampicina (0,1g L-1) + azoxystrobim (0,16 g L-1), a intervalos de 8 e 10 dias a partir do início do experimento, respectivamente nos experimentos 1 e 2. No experimento 1, foi também avaliada a decomposição de tecidos e no experimento 2, as curvas de temperatura das pilhas, conteúdo de fenóis, e presença de microbiota fúngica e bacteriana antagonista a Xcv2Rif. O patógeno sobreviveu em altas densidades (104 a 106 UFC g-1) por pelo menos 80 dias em tecidos infectados de videira na superfície do solo. Portanto, restos de poda de videira constituem importante fonte de inóculo primário para infecção de outras plantas no parreiral. O processo de compostagem eliminou Xcv2Rif de restos culturais em 10 dias, devido às altas temperaturas alcançadas pelas pilhas, liberação de compostos fenólicos durante o processo e antagonismo microbiano. Desta forma, a compostagem constitui uma maneira viável e segura de manejar os restos de poda em parreirais, sem perigo de sobrevivência de Xcv e sem que haja a perda de uma importante fonte de matéria orgânica para a cultura.
177

Evaluation de l'effet du terroir sur la teneur en stilbènes du vin

Gatti, Matteo 28 September 2012 (has links) (PDF)
Le constat que la qualité du vin prend ses origines dans le vignoble est bien enraciné dans la culture européenne. De cette façon, le zonage viticole est à la base de la caractérisation et de la valorisation des produits de terroir tenant compte de l'attention croissante des consommateurs envers les aliments fonctionnels (avec des propriétés nutritionnelles et des bienfaits sur la santé due à leur richesse en molécules comme vitamines et polyphénols). L'enjeu général s'inscrit dans une meilleure compréhension des mécanismes qui sont à la base du fonctionnement de la vigne et de la qualité du vin ainsi que cette étude vise la recherche des terroirs où le taux des stilbènes des vins est le plus élevé. Nous avons considéré deux réseaux de parcelles, l'un de Cabernet franc dans le Saumurois-Touraine (France) et l'autre de Sangiovese di Romagna (Italie). La caractérisation des terroirs et l'analyse des stilbènes des vins issus de chaque parcelle ont été étudiées sur de plusieurs années (de 2003 à 2005 en France, en 2008 et 2009 en Italie) Nous avons identifié cinq UTB dans le Saumurois-Touraine et trois UTB dans le Sangiovese di Romagna. Nos résultats montrent bien que le terroir affecte le métabolisme des stilbènes d'une façon importante et en particulier la teneur en transresvératrol dans le Saumurois-Touraine dépend pour le 58% du terroir. L'effet du millésime (climat) est dominant tandis que l'effet du sol et du sous-sol est secondaire au climat. L'altitude de la parcelle et la teneur en calcaire actif du sol favorisent l'augmentation du resvératrol des vins. La texture du sol affecte le métabolisme des stilbènes ainsi que la teneur en argile augmente la concentration du vin en ces molécules.
178

BIOLOGY, EPIDEMIOLOGY AND MODELLING OF BOTRYTIS CINEREA PERS.:FR., THE CAUSAL AGENT OF GREY MOULD IN GRAPEVINE

CILIBERTI, NICOLA 28 January 2015 (has links)
Gli obbiettivi di questa tesi di dottorato erano: i) valutare l’effetto di differenti condizioni ambientali sulla biologia ed epidemiologia di isolati di B. cinerea appartenenti alle sub-popolazioni transposa e vacuma, e ii) sviluppare un nuovo modello previsionale per predire il rischio di muffa grigia nei vigneti tra le fasi fenologiche di sviluppo delle infiorescenze e maturazione dei grappoli. Gli effetti della temperatura, durata di bagnatura e umidità relativa sulle infezioni di infiorescenze e bacche di Vitis vinifera sono stati valutati con inoculazioni artificiali di isolati di B. cinerea. Gli effetti della temperatura, attività dell’acqua, umidità relativa e composizione delle bacche di uva sulla germinazione dei conidi, crescita miceliale e produzione di conidi sono stati valutati su substrati artificiali. I risultati evidenziano che la capacità di causare infezioni varia con gli isolati indipendentemente dall’appartenenza alle sub-popolazioni transposa o vacuma. Inoltre, le risposte dei differenti isolati al variare delle condizioni ambientali risultano essere simili. Basandosi sui risultati ottenuti sono state sviluppate equazioni matematiche per spiegare l’effetto dei fattori ambientali sull’incidenza delle infezioni di infiorescenze e bacche, germinazione dei conidi, crescita miceliale e produzione di conidi. Un nuovo modello previsionale è stato sviluppato per predire le infezioni di Botrytis cinerea nei vigneti utilizzando le equazioni sviluppate e seguendo un approccio meccanicistico. Il modello è stato validato per 6 anni (2009-2014) in 13 vigneti localizzati in Italia e Francia. Il nuovo modello risulta essere più completo di quelli proposti finora in letteratura e può essere utilizzato per migliorare le strategie di controllo della muffa grigia nei vigneti. / The aims of this Doctoral work were: i) to investigate the effect of different environmental conditions on biology and epidemiology of B. cinerea strains belonging the two transposon types vacuma and transposa, and ii) develop a new weather-driven mechanistic model in order to predict risk of grey mould in vineyards from early growth of inflorescences to berry ripening. The effect of temperature, wetness duration and relative humidity on infection of Vitis vinifera inflorescences and berries was investigated by artificial inoculation of B. cinerea strains. The effect of temperature, water activity, relative humidity and grape berry composition on conidia germination, colony growth and conidial production was investigated in agar-medium. The results showed that the ability to cause infection was a strain rather than a transposon genotype attribute. Moreover, the general response to different environmental conditions is similar among different B. cinerea strains. Based on these data, equations were developed to account the combined effects of environmental factors on infection incidence, conidia germination, colony growth and conidial production. A new previsional model for Botrytis cinerea infections on grapevine was elaborated using the equations developed and following a mechanistic approach. The model was validated over a 6-year period (2009 to 2014) in 13 vineyards located in different grape-growing areas of Italy and France. The model is more complete than the others proposed in literature and represents an improvement to control grey mould in vineyards.
179

Cianamida hidrogenada e fenologia de produ??o em cultivares Pinot Meunier e Pinot Noir no munic?pio de Diamantina/MG. / Hydrogenated cyanamide and phenology of the production in Pinot Meunier and Pinot Noir cultivars in the city of Diamantina/MG.

Moreira, Caio de Oliveira 26 February 2010 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:30Z No. of bitstreams: 5 11.pdf: 692915 bytes, checksum: 5a72c30d2db22b8d986fa5ff6134c4b8 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T14:36:27Z (GMT) No. of bitstreams: 5 11.pdf: 692915 bytes, checksum: 5a72c30d2db22b8d986fa5ff6134c4b8 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T14:36:27Z (GMT). No. of bitstreams: 5 11.pdf: 692915 bytes, checksum: 5a72c30d2db22b8d986fa5ff6134c4b8 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2010 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / O presente estudo teve como objetivo avaliar o efeito da cianamida hidrogenada e a fenologia de produ??o em cultivares Pinot Meunier e Pinot Noir no munic?pio de Diamantina/MG. Os experimentos foram conduzidos em propriedade comercial localizada em Diamantina/MG. O vinhedo foi instalado em 2005 com as cultivares Pinot Meunier e Pinot Noir, enxertadas sobre o porta-enxerto 1103 Pausen, implantado com espa?amento de 1 m entre plantas x 2,5 m entre fileiras. As plantas foram conduzidas com 2 hastes em esquema de espaldeira vertical e tr?s fios de arame. A poda foi realizada em 4 de setembro de 2008, deixando uma haste curta com duas gemas por espor?o. Para a caracteriza??o fenol?gica foram feitas observa??es visuais a cada dois dias da poda at? a colheita. As demandas t?rmicas foram calculadas a partir de temperaturas observadas na Esta??o Meteorol?gica de Diamantina/MG. Para as curvas de matura??o foi utilizado suco para avalia??o qu?mica dos teores de s?lidos sol?veis totais (SST), acidez total titul?vel (ATT) e rela??o SST/ATT. Para avaliar o efeito da aplica??o de cianamida hidrogenada na brota??o, in?cio de matura??o e nas caracter?sticas f?sico-qu?micas das cultivares Pinot Meunier e Pinot Noir cultivadas em Diamantina/MG, foram realizadas avalia??es das plantas a cada dois dias, quando foram aferidas as porcentagens de brota??o e porcentagens de bagas em in?cio de matura??o. Na colheita foi realizada a contagem do n?mero de cachos por planta e foram amostradas 15 bagas por parcela para as seguintes avalia??es f?sico-qu?micas das bagas: umidade, massa, di?metros longitudinal (DL) e transversal (DT), rela??o DL/DT, teor de s?lidos sol?veis totais (SST), acidez total titul?vel (ATT), rela??o STT/ATT, a??cares redutores, antocianinas, flavon?ides, compostos fen?licos e pH. Os resultados obtidos demonstram dura??o do per?odo fenol?gico para as cultivares Pinot Meunier e Pinot Noir de 145 e 155 dias, respectivamente, para a produ??o da safra de ver?o em Diamantina/MG, podendo considerar a variedade Pinot Meunier de ciclo precoce. A exig?ncia t?rmica necess?ria para a produ??o da Pinot Meunier da poda ? colheita foi de 1340,67 GD e da Pinot Noir de 1446,95 GD. A cultivar Pinot Noir apresentou maior teor de s?lidos sol?veis totais e acidez, sendo a maior rela??o SST/ATT da Pinot Meunier nas condi??es de Diamantina/MG. Foram evidenciados para o efeito da aplica??o da cianamida hidrogenada a antecipa??o do in?cio da matura??o em 17 dias para a Pinot Meunier, a maior porcentagem de cachos em in?cio de matura??o em 45,84% e 28,23% para ?Pinot Meunier? e ?Pinot Noir?, respectivamente, e o incremento de algumas caracter?sticas f?sico-qu?micas avaliadas, como acidez total titul?vel, rela??o SST/ATT, flavon?ides e taninos para a cultivar Pinot Meunier e s?lidos sol?veis totais, a??cares redutores e umidade das bagas para a cultivar Pinot Noir. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2010. / ABSTRACT This study aimed to evaluate the effect of hydrogenated cyanamide and phenology of production in Pinot Meunier and Pinot Noir cultivars in Diamantina/MG.?The experiments were conducted in commercial property located at Diamantina/MG.?The vineyard was established in 2005 with the Pinot Meunier and Pinot Noir cultivars, grafted on rootstock Pausen 1103, deployed with a spacement of 1 m between plants and 2.5 m between rows.?The plants were conducted with 2 rods in an arrangement of vertical cordon and three wires.?The pruning was performed on September 4, 2008 leaving a short stem with two buds per spur.?To characterize the phenology were made visually observations every two days from pruning to harvest.?The thermal demands were calculated from the observed temperatures at the meteorological station of Diamantina/MG.?For the maturation curves was used a juice to make chemical evaluation of total soluble solids (TSS), total titratable acidity (TTA) and the TSS/TTA ratio.?To evaluate the effect of hydrogenated cyanamide on sprouting, early maturation and the physicochemical characteristics of the Pinot Meunier and Pinot Noir cultivars grown in Diamantina/MG where the assessments of plants were made every two days, then there were measured the percentage of budding?and the percentage of berries in early maturation.?At harvest it was counted the number of clusters per plant and there were sampled 15 berries per plot for the following physicochemical evaluations of berries: humidity, mass, longitudinal diameter (DL) and transversal diameter (TD), LD/TD ratio content of?total soluble solids (TSS), total titratable acidity (TTA), TSS/ATT ratio, reducing sugars, anthocyanins, flavonoids, phenolic compounds and pH.?The results show that the duration of phenological period for the Pinot Noir and Pinot Meunier cultivars are from 145 to 155 days, respectively, for the production of summer crops in Diamantina/MG, which may consider the Pinot Meunier variety in early maturity.?The thermal requirement needed for the production of Pinot Meunier from pruning to harvest was 1340.67 GD and Pinot Noir presented 1446.95 GD.?Pinot Noir cultivar showed the highest content of total soluble solids and acidic, and also the highest TSS/TTA ratio of Pinot Meunier in the Diamantina/MG environment.?For the purpose of applying hydrogenated cyanamide there were evidenced the anticipation of early maturation in 17 days for Pinot Meunier, the highest percentage of early-ripening in 45.84% and 28.23% for Pinot Meunier and Pinot Noir, respectively and the increment of some physicochemical characteristics evaluated as total titratable acidity, TSS/TTA ratio, flavonoids and tannins for the Pinot Meunier cultivar and total soluble solid, reducing sugars and humidity from the berries to the Pinot Noir cultivar.
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Qualidade da uva e do vinho da Sangiovese submetida ao raleio de cachos em região de altitude / Qiality of grapes and wine from "Sangiovese" subjected to thinning in the region of height

Schlemper, Caroline 06 April 2010 (has links)
Made available in DSpace on 2016-12-08T16:44:35Z (GMT). No. of bitstreams: 1 PGPV10MA052.pdf: 406980 bytes, checksum: 529cbe2c06ed0aa66736487fd0596ce1 (MD5) Previous issue date: 2010-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Viticulture highlands isexpanding in the state of Santa Catarina, but lack of knowledge on the use of cultivars grapes, which need to expand the research to contribute to the development of production systems that improve the quality of grapes for wine production. The aim of this study was to evalate the influence of grapes for wine production. The aim of this study was to evaluate the influence of diferente intensities of thinning, the evolution of physical and chemical characteristics of grape Sangiovese and chemical characteristics of the wine produced from these grapes on Paulsen 1103 rootstock, grown in espalier system. The research was conductedat the company Villa Francioni Ltda., São Joaquim-SDC at na altitude of 1415 meters, in 2007/08 and 2008/09 seasons. The treatment were performed when 50% of the berries had changed color, making the teatments: T1 without ralear T2 15% reduction of the total load of the plant; T3 30% of the total load of the plant, T4 reduction 45% of the total load of the plant. The harvest occurred in April in both seasons, being held on April 16 in 2007/08 and 23 in 2008/09. The practice of thinning influence on the evolution of the chemical characteristics of grapes and wine from the Sangiovese cultivar in the hills of Santa Catarina. For the harvest of 2007/2008, a production with a 30% charge to higher vakues for polyphenols and anthocyanins, the desirable features fine wines. As for the 2008/2009 harvest, showed that treatment without ralear showed the highest results. Given this, it is extremely importante to continue this work to better understand the data, due offer conflicting results compared bibliographies / A viticultura em regiões de altitude está em expansão no estado de Santa Catarina, porém a falta de conhecimento sobre a utilização das cultivares viníferas, necessita que se ampliem as pesquisas para contribuir com o desenvolvimento de sistemas de produção que melhorem a qualidade das uvas destinadas a produção de vinhos. O objetivo deste trabalho consistiu em avaliar a influência de diferentes intensidades de raleio, na evolução das características físicas e químicas da uva Sangiovese e das características químicas do vinho produzido a partir destas uvas, sobre porta enxerto Paulsen 1103, cultivada em sistema espaldeira. A pesquisa foi desenvolvida na empresa Villa Francioni Ltda, município de São Joaquim-SC a uma altitude de 1.415 metros, nas safras 2007/08 e 2008/09. Os tratamentos foram efetuados quando 50% das bagas haviam mudado de cor, compondo os tratamentos: T1 testemunha sem ralear; T2 redução de 15% da carga total da planta; T3 redução de 30% da carga total da planta; T4 redução de 45% da carga total da planta. As colheitas ocorreram no mês de abril em ambas as safras, sendo realizadas no dia 16, na safra 2007/08 e no dia 23 em 2008/09. A prática do raleio influenciou na evolução das características químicas das uvas e do vinho da cultivar Sangiovese na serra catarinense. Para a safra de 2007/2008, uma produção com uma redução de 30% da carga proporcionou maiores valores para polifenóis e antocianinas, características desejáveis a vinhos finos. Já para a safra 2008/2009, demonstrou que o tratamento sem ralear apresentou os maiores resultados. Diante disto, é de suma importância a continuação deste trabalho para melhor compreensão dos dados, devido apresentarem resultados contraditórios comparados as bibliografias

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