Orientador: Marco Antonio Tecchio / Banca: Sarita Leonel / Banca: Giuseppina Pace Pereira Lima / Banca: Mara Fernandes Moura / Banca: Sergio Ruffo Roberto / Resumo: O objetivo desse trabalho foi avaliar a duração dos estádios fenológicos, as demandas térmicas (graus-dia) e o potencial produtivo das videiras, além de determinar o conteúdo de ácidos orgânicos, açúcares, compostos bioativos e a atividade antioxidante em uvas e sucos de uva de cultivares Vitis labrusca e híbridas cultivadas sobre diferentes porta-enxertos sob condições tropicais na região Sudeste do Brasil. O experimento foi realizado em vinhedo experimental do Instituto Agronômico, em Votuporanga, região Noroeste do estado de São Paulo. Foram avaliadas as cultivares Isabel Precoce, BRS Carmem, BRS Cora e IAC 138-22 Máximo enxertadas nos porta-enxertos 'IAC 766' e 'IAC 572'. As características fenológicas e produtivas das videiras foram avaliadas em três ciclos produtivos (2015/2016), dos quais, em um ciclo foram analisados os compostos bioativos (antocianinas, flavonóis, estilbenos, ácidos fenólicos e flavanóis) nas películas e polpas das uvas e nos sucos integrais de uva. Além das cultivares citadas anteriormente, os compostos bioativos das uvas foram analisados também na uva 'BRS Violeta'. Os resultados mostraram que a duração do ciclo produtivo das videiras 'Isabel Precoce', IAC 138-22 'Máximo', 'BRS Cora' e 'BRS Carmem' foi de, aproximadamente, 115, 117, 119 e 138 dias, respectivamente, variando em função das condições climáticas ocorridas durante o ciclo. O acúmulo de graus-dia foi proporcional ao número de dias necessários para as videiras atingirem cada estádio fenol... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this work was to evaluate the duration of the phenological stages, the thermal demands (degree-days) and the yield potential of the vines, besides determining the content of organic acids, sugars, bioactive compounds and the antioxidant activity in grapes and grape juices of Vitis labrusca and hybrids cultivars grown onto different rootstocks under tropical conditions in the Southeast region of Brazil. The experiment was conducted in an experimental vineyard of the Instituto Agronômico (IAC), in Votuporanga, Northwest region of the São Paulo state. The cultivars Isabel Precoce, BRS Carmem, BRS Cora and IAC 138-22 Máximo grafted onto 'IAC 766' and 'IAC 572' rootstocks were evaluated. The phenological and productive characteristics were evaluated in three seasons (2015/2016), of which in the second season the bioactive compounds (anthocyanins, flavonols, stilbenes, phenolic acids and flavanols) were assessed in pulps and skins of the grapes and in the whole grapes juices. Additionally to the cultivars above mentioned, the bioactive compounds of the grapes were also assessed in the 'BRS Violeta' grape. The results showed that the duration of the productive cycle of Isabel Precoce, IAC 138-22 Máximo, BRS Cora and BRS Carmem cultivars was approximately 115, 117, 119 and 138 days, respectively, which might change according to the climatic conditions during the growing season. The summation of degree-days was proportional to the number of days demanded for the vines to reach each phenological stage. The cultivars Isabel Precoce, IAC 138-22 Máximo and BRS Cora were the most productive. The 'BRS Carmem' and 'Isabel Precoce' grapes presented balanced levels of soluble solids and acidity. By contrast, IAC 138-22 'Máximo' grapes presented limited potential in the accumulation of sugars. The rootstocks did not influence the phenology and summation of degree-days of the vines ... / Doutor

Este estudo teve como objetivo central identificar quais fatores locacionais influenciaram a tomada de decisão de expandir os investimentos da atividade vitivinícola por parte dos empresários atuantes na Serra Gaúcha - principal pólo vitivinícola do país. Observou-se um movimento de expansão territorial da atividade vitivinícola para novas regiões do Rio Grande do Sul (Serra do Sudeste e Campanha) e para o Vale do São Francisco (Bahia e Pernambuco), regiões em que, anteriormente, não havia a prática de tal cultura. As informações da presente pesquisa foram obtidas através de entrevista direta, orientada por um questionário, com representantes das vinícolas. A abrangência da pesquisa foi de 73,3% da população alvo e foi realizada nos meses de dezembro/2005 no Rio Grande do Sul e janeiro/2006 no Vale do São Francisco. Os dados das entrevistas foram tratados com aplicação da estatística descritiva, pois grande parte das perguntas foi de ordem qualitativa. A hipótese que circunda este estudo é de que na agroindústria, as variáveis que envolvem a matéria-prima (qualidade, local de fornecimento) são os principais fatores que influenciam a tomada de decisão do sítio de produção. Como referencial teórico, associou-se as teorias relacionadas aos fatores locacionais com a teoria de Bowersox (1978). Através da pesquisa, pode-se verificar que a atividade vitivinícola brasileira mostrou estar condicionada à distribuição espacial dos recursos produtivos, destacando-se os fatores edafoclimáticos, qualidade da matéria-prima, fator comportamental do empresário e disponibilidade de terras. A pesquisa revelou que as empresas estão preocupadas com a qualidade final do produto (vinho), a qual é otimizada pela qualidade da matéria-prima (uva) que, por sua vez, depende das condições edafoclimáticas da região produtiva. Tal preocupação e/ou necessidade provocou esta expansão geográfica da atividade para a Serra do Sudeste e Campanha (no estado do Rio Grande do Sul) e no Vale do São Francisco. Esta última região também se mostrou alvo de investimentos estrangeiros e tornou-se (e ainda se torna) atrativa por apresentar excelentes condições edafoclimáticas, capacidade de duas safras por ano e produção constante no decorrer do ano, além de instalações processadoras de menor porte. / The purpose of this work is to identify which locational variables influenced the decision made by producers from the state of Rio Grande do Sul (RS), main viticulturist state in Brasil, to expand investments on the wine industry. There was a movement of territorial expansion of wine production to new regions in RS (Serra do Sudeste and Campanha) and to Vale do São Francisco, in the states of Bahia and Pernambuco, regions in which he grape agriculture hadrit started yet. The direct-interview with viticulturists was the main source of information used by this work. This research embraced 73,3% of the producers investing in those new regions, and it was conducted during December/2005, in the State of Rio Grande do Sul, and January/2006, in Vale do São Francisco. Descriptive statistic has been applied to summarize the data obtained with the interviews, due to qualitative variables representing most of the questions. The main hypothesis of this work suggests that in the agroindustry, variables involving raw material (quality, supplier) are the main factors in making the decision as to production area. A review of Bowersox Theory (1978) associated with the theory of locational factors was employed as theoretical referential. As for results, it was possible to validate that Brazilian viticulture was conditioned to the place distribution of productive resources, standing out the following factors: edaphoclimatics, raw material quality, manager behavior and land availability. Thus, the research revealed that companies have been concerned regarding the quality of the final product (wine), which is optimized through raw material quality (grape) that depends on edaphoclimatic conditions of the productive area. Indeed, the need to achieve a higher level of quality forced the viticulture to expand its production area to Serra do Sudeste and Campanha (RS) and Vale do São Francisco, which has recently turned into an attractive area to foreign investment, because of its excellent edaphoclimatic conditions, two harvests a year, continuous output year round and a small agroindustry.

O setor agrícola brasileiro gera saldos positivos à balança comercial do Brasil, e a fruticultura segue no mesmo ritmo. Dentre as frutas produzidas no Brasil, a uva é uma das que mais impactam na balança comercial, tendo em vista que é amplamente exportada e importada. Este cenário só se tornou possível com a abertura de mercado na década de 90, e, assim, o Brasil pôde se tornar mais competitivo no mercado nacional e internacional. A competitividade é importante para a economia, seja de um país, de um setor ou de uma empresa. No presente trabalho, então, foi realizada uma análise setorial da competitividade da viticultura, fundamentada na produtividade, nos aspectos tecnológicos e no ambiente institucional. Para a análise regional brasileira foi utilizada a técnica de triangulação na metodologia deste trabalho: pesquisa qualitativa (entrevista com produtores das principais regiões produtoras de uva de mesa do Brasil); análise estatística por meio de Modelos Lineares Generalizados de dados secundários (preço nas regiões produtoras de uva de mesa) obtidos no banco de dados do Cepea; e análise documental (com base nas legislações, regras e outros documentos disponíveis). A partir disso foi constatado que o Vale do São Francisco (BA/PE) é a região brasileira mais competitiva, visto que investe mais em tecnologia, tem gestão empresarial (enquanto as outras são marcadas pela agricultura familiar) e consegue se sobressair nas questões de comercialização. Além disso, no Brasil, o ambiente institucional, de um modo geral, não gera grandes vantagens competitivas para nenhum produtor de uva - a exceção são as fortes cooperativas do Nordeste. Para a análise da competitividade internacional, além da análise documental com vistas ao comércio internacional, foram feitas estatísticas descritivas com dados de preço, produção, produtividade, exportação, importação e consumo aparente de uva de mesa do Brasil, Chile e Itália. Os dados foram obtidos nos bancos de dados do IBGE, MDIC, Odepa, Eurostat e USDA. No geral, Chile e Itália têm ambiente institucional mais forte que o Brasil para o comércio internacional de uva de mesa. Mesmo assim, a competitividade internacional brasileira cresceu nos últimos anos frente a Chile e Itália. Assim, pode-se concluir que mesmo com ambiente institucional desfavorável, tanto no mercado interno quanto no externo, o Brasil conseguiu avançar na competitividade entre os anos analisados neste trabalho. Isso se deve, sobretudo, aos investimentos ocorridos na principal região brasileira - o Vale do São Francisco. / The Brazilian agribusiness generates profits to the trade balance of Brazil, and the fruit sector follows the same rhythm. The table grape is one of the fruits that impact the trade balance, because it is widely exported and imported. This scenario was only possible to the market opening in the 90s, and thus Brazil was able to become more competitive in domestic and international markets. Competitiveness is important to the economy, whether of a country, of a sector or a company. Thus, a sectorial analysis of the viticulture competitiveness was conducted, based on productivity, technological and institutional environment. In this research, it was used triangulation technique in the methodology to conduct the Brazilian regional analysis: qualitative research (interview with producers of the main producing regions of table grape of Brazil); statistical analysis using Generalized Linear Models of secondary data (price of table grape) obtained in Cepea database; and documental analysis (based on the laws, rules and other documents available). Based on this, it was found that the São Francisco Valley (BA/PE) is the most competitive region in Brazil. This region invests more in technology, has business management (while the others regions are tagged by family farmers) and stands out in the marketing. In addition, in Brazil, the institutional environment, in general, does not generate competitive advantages for grape growers - the exception is the strong cooperatives located in Northeast. The international competitiveness was conducted by descriptive analysis of statistics - price, production, productivity, export, import and apparent consumption of table grape in Brazil, Chile and Italy. Also, a documental analysis of international trade was conducted. Data were obtained from the IBGE, MDIC, Odepa, Eurostat and USDA databases. Overall, Chile and Italy have a stronger institutional environment to international trade of table grapes than Brazil. Anyway, the Brazilian international competitiveness has increased in recent years compared to Chile and Italy. Thus, it can be concluded that even with unfavorable institutional environment, both domestically and external, Brazil was able to advance in competitiveness during the years analyzed in this work. This is mainly attributed to the investments occurred in the main Brazilian table grape region - São Francisco Valley.

A three-year study was conducted at a commercial vineyard site in California’s Edna Valley AVA to evaluate the physiological and agronomical effects of the timing of cluster thinning on Pinot noir (clone 115) grapevines. Vines were thinned to one cluster per shoot at three selected time-points during the growing season (bloom, bloom + 4 weeks, bloom + 8 weeks), and fruit from each treatment was harvested and made into wine. Across all growing seasons, yield decreased 43% in thinned vines relative to un-thinned control vines. No effect of cluster thinning or interaction with growing season was found in vine shoot diameter, internode length, fruit zone light level, or cluster weight. Growing season significantly affected more fruit and wine parameters than did cluster thinning treatment, with interactions between treatment and growing season found in fruit Brix, titratable acidity, and anthocyanins, as well as wine anthocyanins and wine b* (yellow component). For example, bloom + 8 and bloom + 12 thinning treatments advanced Brix in 2017 but had no effect in 2018. Cluster thinning treatments increased berry anthocyanins by 43% in 2017 and by 103% in 2018 relative to the control. Similarly, cluster thinning increased berry total phenolics by 87% in 2017 and by 140% in 2018 relative to the control, with no significant differences found between the different thinning treatments. However, the levels of anthocyanins and total phenolics were generally not affected by cluster thinning treatment in the resulting wines. The fact that different cluster thinning treatments resulted in nil or minor effects on fruit and wine suggests that the vines tested were at or below a balanced crop load prior to the application of cluster thinning. Edna Valley AVA could likely support higher crop loads than 3.2 on the Ravaz index without negatively impacting fruit or wine composition and reducing crop load below that level is unlikely to increase fruit or wine quality.

The building, combining the production of wine, accommodation and restaurant is surrounded by vineyards overlooking the Novomlýnské reservoir and Palava Hills. Part of the proposal are too small constructions in the landscape, which offers its users an added value in the perception of the cultural landscape. The basic idea itself winery is an intersection that connects the four routes, each of which is determined by another user.

Viniculture and wine-making from a legal viewpoint Abstract This thesis is primarily a theoretical treatise on the legal regulation of viticulture and wine-making in the Czech Republic. It aims to provide an overview of the current legal regulation of the most important institutes of both aforementioned fields, focusing on the Act No. 321/2004 Coll. on viniculture and winemaking, but also other laws and sources of law with regard to EU legislation. Emphasis is placed on the individual aspects of viticultural activity and the subsequent manufacturing of wine products and the conditions for their marketing. This thesis is divided into 8 chapters, including an introduction and a conclusion. The introductory chapters are focused on defining the position of the wine law in the legal system of the Czech Republic and clarifying the relations between the sources of law of viticulture and wine-making in the context of EU legislation. The main body of this thesis is included in chapters No. 3 and No. 4. These chapters are devoted to the current legislation in the field of viticulture and wine-making. The viticultural part of the work is focused mainly on the regulation of vine planting and some aspects which are closely related to viticultural activity, such as phytosanitary care and fertilization. In the wine-making...

Wine vineyards in humid environments like the mid-Atlantic United States are characterized by vines that develop too much vegetative growth for optimum quality wine production. Cover crops, rootstocks and rootzone restriction were evaluated for their effect on vegetative and reproductive growth on Cabernet Sauvignon. Treatments were arranged in a strip-split-split plot arrangement with under-trellis cover crops (UTCC) compared to row-middle only cover crop combined with 1-m weed-free strips in the vine row as main plots. Rootstocks riparia Gloire, 420-A, and 101-14 were sub-plots, while sub-sub-plots comprised two treatments: vines were either planted in root-restrictive (RR), fabric bags (0.016 m3) at vineyard establishment (2006), or were planted without root restriction. All three factors were effective in suppressing vegetative development as measured by rate and extent of shoot growth, lateral shoot development, trunk circumference, and dormant pruning weights. Canopies of vines with UTCC and RR had reduced leaf layer values by approximately 21% and 23% compared to conventional controls. The principal effect of the UTCC and the RR treatments was a sustained reduction in stem (xylem) water potential. UTCC and RR caused significant 7 and 10% reductions in berry weight, compared to their conventional controls. Berry weights of vines grafted to riparia were greater than those of vines grafted to other rootstocks. Wine made from UTCC and RR treatments increased red wine color compared to herbicide UTGC and NRR, respectively. This study identified treatments that improve vine balance while simultaneously improving grape composition and potential wine quality. / Master of Science

The state of Virginia was analyzed to establish its suitability for grape culture. This investigation occurred in two phases: a small scale analysis that encompassed the entire state, and a large scale analysis which focused on site selection at the local level. After identifying regions across the state in terms of their viticulture potential, a study area was chosen from within the highest ranking region. This study area was the focus for the local-scale site potential analysis. First, to delineate regions across Virginia that had greater or lesser viticulture potential from a physical and climatological basis, weather station data were collected for minimum winter temperatures, maximum summer temperatures, precipitation, length of growing season, and day versus night temperature differentials. In addition, elevation and slope models were constructed to complement the climatic variables in identifying areas that contained factors most conducive to grape production. To validate this regional assessment, the history of fruit industries within the state are outlined geographically to display the evolution of the fruit industries, and to establish the factors which have shaped the current fruit landscape. Secondly, at the local scale, a Geographic Information System (GIS) approach was used to identify sites at the county scale that had greater or lesser viticulture potential from a physical basis. Composite maps, constructed by individual counties in the state, were produced from a series of physical databases. The individual databases (sources and resolution in parentheses) included land-use (Virginia Gap Analysis; 30meter² resolution), slope, aspect, and elevation (USGS 1:24,000 Digital Elevation Model; 30meter²), and soils data (USGS Digital Line Graph (DLG-3)). Each physical feature layer was given a numerical classification, then all layers were combined to produce a 0 to 100 scale in the final, composite image. Given this model of potential vineyard suitability, existing fruit operations in select counties were geo-located on each feature layer using a Global Positioning System (GPS: 1-2meter accuracy). Actual data on occurrences of frosts, minimum winter temperatures, and other site variables were collected from these fruit operations and surrounding weather stations as a sample to validate the model. A strong correlation between areas containing characteristics of current fruit acreage--namely apple--and sites high in potential for viticulture according to the model. Studying the history of geographic distribution of apple and grape industries across the state reinforces the regional assessment of viticulture potential, formulated by the climatic and topographic analysis. Employment of GIS approach at the local site scale was shown to be an effective tool for site selection at the local scale with certain caveats. In addition, the evaluation procedure integrating GIS and GPS technologies allows us to visually assess the distribution pattern of each of the factors employed individually; and, in turn, physically identify and locate areas of viticulture potential created from the combination of those factors. / Master of Science

Thesis (PhD(Agric))--Stellenbosch University, 2012 / ENGLISH ABSTRACT: Field spectroscopy was used to study leaf composition and selected factors (including canopy growth manipulation and water status changes) that may impact on it in a Vitis vinifera cv. Shiraz vineyard, showing considerable variability in vigour. Temporal and spatial variability in leaf composition were incorporated into measurements by analysing leaves in different shoot positions and at different developmental stages during three different growing seasons. Irrigation and canopy manipulation treatments were also imposed in order to provide new insights into assessing the grapevine leaf and possibly also the canopy growth and ageing dynamics as well as pigment content, as a basis of executing a generally non-destructive measurement approach. Despite large climatic differences between the seasons, canopy size seemed of crucial importance in determining grapevine water relations in the grapevines from the different canopy manipulation treatments. Drastic compensation effects in terms of secondary shoot growth also followed the canopy reduction treatment. Despite this, canopy microclimate was apparently improved, considering the results from light measurements as well as the ripening dynamics in the reduced canopies. Reduced canopies also seemed to display a different canopy composition, in favour of secondary growth. This could have impacted positively on water use efficiency as well as ripening, due to higher photosynthetic efficiency of these leaves during the ripening stages. The reduced canopy treatments offered the possibility of attaining technological ripeness at an earlier stage and at comparatively lower potential alcohol levels. This study illustrated the relevance of considering the vegetative development of the grapevine, along with leaf ageing in the canopy, when conducting calibrated non-destructive measurements of leaf pigments, structure and water content. The relevance of using multivariate techniques in leaf spectroscopy was shown. This can be applied and simplified to aid in non-destructive leaf pigment, structure and water content estimation in future studies. Even with the general variation encountered in this vineyard, predictions of the major pigments in grapevine leaves were within acceptable error margins. Further work is required to improve the modelling of xanthophylls, which may require non-linear multivariate techniques. Logistical shoot growth modelling was used in leaf age estimation and classification, which made it possible to simplify statistical analysis of the leaf parameters mentioned. Practical application of the modelled and predicted parameters was shown for a specific period in season two by comparing the reaction of different treatments to developing water deficits. The results indicated that several parameters, with special mention of the carotenoid:chlorophyll ratio and chlorophyll a:b ratio, can be monitored on young and old leaves in the canopy in order to monitor developing water deficit stress. The modelled parameters, however, did not seem to be sensitive enough to allow specific prediction of predawn leaf water potential values. Specific leaf mass, equivalent water thickness, total specific leaf mass as well as leaf chronological age were successfully predicted from leaf spectral absorbance data, and this may be useful in future work on quantifying leaf adaptation to the micro-environment within the canopy. / AFRIKAANSE OPSOMMING: Veldspektroskopie is gebruik om blaarsamestelling en spesifieke faktore (insluitend lowergroei manipulasie en waterstatus veranderinge) wat ‘n impak kan hê in ‘n Vitis vinifera cv. Shiraz wingerd, met beduidende variasie in groeikrag, te ondersoek. Ruimtelike, asook tydsgebonde, variasie in blaarsamestelling is geïnkorporeer in die metings deur blare van verskillende lootposisies en vir verskillende ontwikkelingstadia gedurende drie verskillende groeiseisoene te meet. Besproeiings- en lowermanipulasie behandelings is ook uitgevoer om die dinamiek van blaar- en lowergroei, veroudering, asook pigmentinhoud te bestudeer binne die konteks van die uitvoering van ‘n nie-destruktiewe meetstrategie. Ondanks groot klimaatsverskille tussen die seisoene, blyk lowergrootteverskille belangrik te wees in die bepaling van wingerdstok-waterverhoudings in die verskillende lowermanipulasie behandelings. Drastiese kompensasiereaksies ten opsigte van sylootgroei is waargeneem in reaksie op die gereduseerde lowerbehandeling. Indien die resultate van ligmetings en druifrypwording in die gereduseerde lowerbehandeling in ag geneem word, is lowermikroklimaat egter steeds verbeter. Hierdie behandeling het oënskynlik ook veranderde lowersamestelling gehad, tot voordeel van sylootgroei. Dit kon moontlik ‘n positiewe invloed gehad het op waterverbruikseffektiwiteit asook druifrypwording, as gevolg van moontlike hoër fotosintetiese effektiwiteit van die blare gedurende die rypwordingstadia. Die gereduseerde lowerbehandeling het die moontlikheid gebied om tegnologiese rypheid by ‘n vroeër datum te bereik, met moontlike laer alkoholvlakke in die wyn. Hierdie studie het die belangrikheid beklemtoon om die vegetatiewe ontwikkeling van die wingerdstok in ag te neem wanneer gekalibreerde nie-destruktiewe metings van blaarpigmente, blaarstruktuur asook waterinhoud onderneem word. Die belang van multi-variant meettegnieke in blaarspektroskopie is aangetoon. Dit kan verder vereenvoudig word ter ondersteuning van niedestruktiewe meting van blaarpigment, -struktuur en -waterinhoudsbepaling in toekomstige studies. Selfs met die variasie wat in die wingerd voorgekom het, was die voorspellings van die vlakke van die belangrikste pigmente wat in wingerdblare aangetref word binne aanvaanbare foutgrense. Opvolgwerk is nodig om die modellering van xanthofil te verbeter, aangesien dit moontlik nielineêre multi-variant analise mag benodig. Logistiese groeimodellering is gebruik om blaarouderdom te bepaal en te klassifiseer, wat dit moontlik gemaak het om statistiese analise te vereenvoudig vir die genoemde blaarparameters. Die praktiese toepassing van die gemodelleerde en voorspelde parameters is aangetoon vir ‘n spesifieke gedeelte in seisoen twee, deur die reaksie van verskillende behandelings op toenemende watertekorte te bestudeer. Resultate het aangetoon dat verskeie parameters, met spesifieke klem op die karotenoïed:chlorofil verhouding, asook die chlorofil a:b verhouding, gemoniteer kan word op jong en ouer blare in die lower ten einde ontwikkelende waterstrestoestande te identifiseer. Die gemodelleerde parameters was egter klaarblyklik nie sensitief genoeg vir akkurate voorspelling van voorsonsopkoms-waterpotensiaalvlakke nie. Spesifieke blaarmassa, ekwivalente waterdikte, totale spesifieke blaarmassa, sowel as blaarouderdom kon suksesvol voorspel word deur gebruik te maak van absorpsieblaarspektroskopie, wat nuttig kan wees in toekomstige studies wat handel oor die kwantifisering van blaaraanpassing by die mikro-omgewing binne ‘n wingerdlower.

Thesis (PhD(Agric))--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A lack of defects is required for successful table grape marketing, which pre-suppose optimal vine performance, berry development and post-harvest quality. The supply of mineral nutrients affects vine development, physiology and berry quality. Despite a vast amount of research conducted over decades, there remain many unresolved issues regarding table grape vine nutrition to ensure optimal table grape quality and shelve-life. Unjustified fertilisation practices often include excessive applications of nitrogen (N), potassium (K) and calcium (Ca). A four-year field trial was therefore conducted on a sandy soil in the Paarl district of South Africa, using grafted on Ramsey, and trained to a gable trellis system. Nitrogen, potassium and calcium were applied, singular or in combination, at rates up to 300% the calculated annual nutritional requirement. The effect of these excessive applications on table grape performance under typical South African cultivation conditions was investigated for Vitis vinifera L. cv. Prime Seedless, a very early seedless table cultivar that is produced with minimum berry diameter of 18mm, with special reference to 1) vegetative growth, 2) expression of grapevine nutrient availability through foliar analyses, 3) berry nutrient accumulation patterns of this early cultivar, 4) manipulation of berry nutrient content through soil and bunch directed applications and 5) the effect of berry nutrient content on its quality. No definite vegetative growth responses (expressed as shoot length, leaf surface area and shoot mass) and leaf chlorophyll content differences were obtained for all the treatments. These results were obtained in a vineyard on a sandy soil where excessive N fertilisation caused a reduction of soil pH to detrimentally low levels and where the excessive N, K and Ca applications reduced mutual concentrations and that of Mg, in the soil. A lack of stimulation in vegetative growth may therefore be ascribed to the combined negative effect of these excessive applications on soil pH and vine nutrition. Although the N content of petioles was higher for treatments where N was applied, consistent significant increases in petiole N with N fertilisation were not observed. Petiole N concentration showed a decreasing trend throughout the season. Petiole K concentrations were significantly increased by the K fertilisation at all phenological stages. None of the K fertilisation treatments, however, succeeded to raise petiole K concentrations above the accepted maximum norms and petiole K concentration at a specific sampling stage varied significantly between the four seasons. A general decrease in petiole K concentration was found for all seasons. Calcium fertilisation did not increase soil Ca content, resulting in a lack of differences in petiole Ca concentrations between treatments. An increase in petiole Ca concentration towards harvest was obtained. Correlations between petiole nutrient concentration and berry mineral content at harvest were poor. The only way of knowing the mineral content of berries would seem to be by measuring it directly instead of deducing it from the results of leaf or petiole analyses. The dynamics of berry growth impacted on berry nutrient concentration. Early rapid berry growth, predominantly due to cell division and cell growth, was associated with the most rapid decreases in N, P and Ca concentration. Due to mobility of K and Mg in the plant, that exceeds other nutrients, the decrease in concentration of these two mineral elements was not as pronounced as that of the others. Nutrient accumulation was most rapid during the pre-véraison period, but only Ca showed a definite termination during the early ripening period. The continued inflow of N, P, K and Mg, albeit at slower rates immediately after véraison, should be taken into consideration when fertilisation is applied. As a table grape, total accumulation of each nutrient in Prime Seedless berries also far exceeded that of other cultivars studied thus far. A particular difference is that the berry flesh:skin ratio is much higher than that of previously studied cultivars, leading to higher levels of nutrient accumulation in the flesh. Slightly larger berry size was obtained for N applications and is ascribed to slight increases in early vegetative growth, allowing a better response to GA3 treatments. The use of GA3 for berry enlargement is also considered the reason why K fertilisation, resulting in increased berry K levels, did not affect berry size, as is often found for wine grapes. Higher available NO3 - in the soil on account of excessive N applications resulted in higher levels of berry N, despite sub-optimal soil pH regimes that were created by these treatments. Berry K concentration and content were increased by K fertilisation. Rapid vine K uptake and translocation to the berries seem to negate the reduced vine nutritional status as observed in petioles for situations of over-fertilisation with N. Berry Ca levels were not increased by Ca fertilisation or by bunch applied Ca. The rapid rates of berry growth, together with low rates of berry Ca uptake and Ca uptake that terminates at the onset of ripening, are assumed to be the main reasons for this result. Low levels of decay as well as a lack of consistently increased decay were obtained for N containing treatments. Nitrogen levels in the berries above which their susceptibility to fungal infection is increased, should be established. Information on specific N compounds that may lead to more susceptibility is required. Potentially increased berry browning on account of high rates of K fertilisation needs to be further investigated; indications that this may occur were observed. Neither soil applied Ca nor bunch applied Ca improved berry quality, although Ca treatments seemed to reduce decay during the only season that significant differences were obtained. The negative effect of excessive fertilisation on soil chemistry of sandy soils has again been highlighted by this study. This annuls the fertilisation, leading to inefficient fertilisation and a lack of the desired responses. As indicator of vine nutrient availability, petiole analysis, was proven unreliable and should be evaluated in parallel with soil analyses, taking seasonal variation into consideration. The danger of being only guided by published norms for leaf nutrient concentrations when establishing fertilisation practices has again been highlighted by this study. This research indicated that for a very early cultivar like Prime Seedless, nutrient accumulation dynamics can already start to change during the pre-véraison period in some seasons. This is due to different edaphic and climatic conditions as well as berry size, which leads to much higher flesh:skin ratios. Future research on table grapes would need to develop an understanding of the various factors and dynamics that determine berry nutrient concentration and accumulation of early ripening, large berry sized, seedless table grape cultivars. / AFRIKAANSE OPSOMMING: Suksesvolle bemarking van tafeldruiwe is ten nouste afhanklik van die beskikbaarheid van druiwe sonder defekte, wat ‘n direkte verband met optimale wingerdprestasie, korrelontwikkeling en na-oes kwaliteit inhou. Voorsiening van minerale voedingstowwe beïnvloed die stok se groei, fisiologie en korrelgehalte. Ten spyte van ‘n oorweldigende hoeveelheid navorsing wat oor dekades reeds gedoen is, is daar steeds onopgeloste kwessies aangaande bemesting van tafeldruiwe vir optimale druifgehalte en houvermoë. Die gevolg is onoordeelkundige bemestingspraktyke wat o.a. aanleiding gee tot oorbemesting met stikstof (N), kalium (K) en kalsium (Ca). ‘n Vier-jaar-lange veldproef is gevolglik op ‘n sandgrond in die Paarl distrik (Suid-Afrika) onderneem deur gebruik te maak van Vitis vinifera L. cv. Prime Seedless geënt op Ramsey en op ‘n dubbel-gewel prieelstelsel opgelei is. Stikstof, K en Ca is alleen, of in kombinasie, toegedien teen hoeveelhede gelykstaande aan 300% van die wingerd se jaarlikse behoefte. Die effek van hierdie oormatige toedienings op tafeldruif prestasie onder Suid-Afrikaanse verbouingstoestande is ondersoek, met spesiale verwysing na 1) vegetatiewe groei, 2) uitdrukking van voedingstofbeskikbaarheid deur blaarontledings, 3) die voedingstof akkumulasie patrone van korrels van hierdie vroeë kultivar, 4) manipulasie van korrel voedingstofinhoud deur grond en trosgerigte toedienings en 5) die effek van korrel voedingstofinhoud op kwaliteit. Die doel van die proef was om bemestinspraktyke van Prime Seedless, ‘n baie vroeë pitlose tafeldruifkultivar met ‘n minimum korrelgrootte van 18 mm, te verfyn. Deur die akkumulasie patrone van die druiwe uit te klaar is daar ook ondersoek ingestel of oestyd en na-oes gehalte deur oormatige toediening van voedingstowwe affekteer word. Geen duidelike verskille betreffende vegetatiewe groeireaksies (uitgedruk as lootlengte, blaaroppervlaktes en lootmassas) asook verskille in blaar chlorofilinhoud is vir die behandelings verkry nie. Hierdie resultate is verkry in ‘n wingerd op ‘n sandgrond, waar oormatige N-bemesting aanleiding gegee het tot grond pH verlagings tot die peil van nadelige vlakke. Verder het die oormatige N, K en Ca toedienings wederkerige verlagings in konsentrasies, asook op dié van Mg, in die grond teweeggebring. Die tekort aan vegetatiewe groeiresponse op die behandelings kon dus toegeskryf word aan ‘n gekombineerde effek van die oormatige toedienings op grond pH en voedingstofbalanse. Hoewel die N-inhoud van bladstele hoër was vir behandelings wat N toediening ingesluit het, was daar nie konstante toenames in die vlakke verkry nie. Bladskyf N-konsentrasie het afgeneem deur die loop van die groeiseisoen. Vir alle fenologiese stadiums was bladskyf Kkonsentrasies betekenisvol verhoog deur K-bemesting. Nie een van die Kbemestingsbehandelings het egter daarin geslaag om bladskyf K inhoud vir enige monstertyd bo die algemeen aanvaarde maksimum norms te lig nie. Verder het bladskyf K inhoud by ‘n spesifieke fenologiese stadium ook betekenisvol tussen seisoene verskil. Die K-inhoud van bladskywe het afgeneem met verloop van die seisoen. Kalsiumbemesting het nie die grond se Ca inhoud deurgans verhoog nie, wat dus die tekort aan verskille in Ca konsentrasies tussen die behandelings verklaar. ‘n Toename in Ca konsentrasie en korrel Ca inhoud is vanaf set tot oes waargeneem. Swak korrelasies tussen bladskywe se voedingstofinhoude en korrels se voedingstofinhoude is verkry. Die enigste manier waarop korrels se voedingstofinhoude dus afgelei kan word, blyk te wees deur direkte bepaling daarvan. Voedingstofinhoude van korrels is deur groeipatrone daarvan beïnvloed. Vroeë korrelgroei, hoofsaaklik a.g.v. seldeling en selgroei, het met die vinnigste afnametempo van N, P en Ca gepaard gegaan. As gevolg van die hoër beweeglikheid van K en Mg in die plant in vergelyking met ander voedingstowwe, was die afname in konsentrasie van hierdie twee elemente nie so groot soos vir die ander nie. Voedingstofakkumulasie was die vinnigste in die periode voor deurslaan. Slegs Ca het ‘n beeïndiging van opname aan die einde van hierdie periode getoon. Die voortgesette opname van N, P, K en Mg, alhoewel stadiger kort na deurslaan, moet in ag geneem word wanneer bemesting toegedien word. Vir hierdie kultivar het die totale opname van elke bemestingstof dié van die ander kultivars wat tot hede bestudeer is, ver oorskry. ‘n Spesifieke verskil is ‘n baie hoër vleis:dop verhouding as wat vir ander kultivars verkry is. Dit gee aanleiding tot baie hoër vlakke van voedingstofakkumulasie in die vleis. Effens groter korrelgroottes is verkry waar N toedienings gemaak is. Dit word toegeskryf aan klein toenames in vroeë vegetatiewe groei, wat dus beter reaksie op GA3 behandelings tot gevolg gehad het. Die gebruik van GA3 vir korrelvergroting word ook beskou as die rede waarom K-bemesting, wat tot hoër vlakke van K in die korrels aanleiding gegee het, nie korrelgrootte, soos by wyndruiwe, bevorder het nie. Hoër NO3 - in die grond (water), na aanleiding van N toedienings, het aanleiding gegee tot hoer vlakke van N in die korrels. Dit het plaasgevind ten spyte van sub-optimale grond pH wat deur die oormatige N toedienings veroorsaak is. Korrel K konsentrasie en -inhoud is deur K-bemesting verhoog. Vinnige opname en translokasie van K na die korrels het ook geblyk die rede te wees waarom die verlaagde voedingstatus van die stokke a.g.v. oorbemesting met N nie die korrels se K inhoud geaffekteer het nie. Die vinnige groeitempo van die korrels, tesame met lae vlakke van Ca opname, asook korrels se Ca opname wat tydens rypwording ophou, word as die redes vir die tekorte aan behandelingseffekte beskou. Lae vlakke van bederf, asook ‘n tekort aan betroubare tendense dat bederf deur Nbemesting verhoog word, is verkry. Daar moet vasgestel word of daar N vlakke in die korrels is waarbo hul vatbaarheid vir swaminfeksies verhoog word, en of daar spesifieke N verbindings is wat die korrels meer vatbaar maak vir bederf. Indikasies dat K-bemesting interne verbruiningsvlakke verhoog het, regverdig verdere ondersoek. Korrelkwaliteit is nie deur grond- of trosgerigte toedienings bevoordeel nie. Die negatiewe effek van oormatige bemesting op die chemiese samestelling van sandgronde is weer deur hierdie navorsing uitgelig. Dit lei tot oneffektiewe bemesting en ‘n tekort aan die verlangde effekte. Blaarontledings blyk onbetroubaar te wees as aanduiding van voedingstof beskikbaarheid. Dit moet evalueer word saam met grondontledings en ook seisoenale variasie in ag neem. Die gevaar om slegs deur gepubliseerde norme gelei te word wanneer bemestingspraktyke bepaal word, is weer deur hierdie navorsing uitgelig. Voorst is daar in hierdie navorsing gevind dat voedingstof akkumulasiepatrone van ‘n baie vroeë kultivar soos Prime Seedless alreeds voor deurslaan begin verander a.g.v. omgewingstoestande en korrelgroei wat tot ‘n veel hoër vleis:dop verhouding aanleiding gee. Toekomstige navorsing op tafeldruiwe behoort die faktore en dinamika wat voedingstofkonsentrasie en -akkumulasie in korrels van vroeë, groot korrel, pitlose tafeldruifkultivars beïnvloed verder te ondersoek.