Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The effect of partial rootzone drying (PRD) on the composition of grape and wine secondary metabolites was investigated. At harvest, total anthocyanin and phenolic concentration in fruit of Vitis vinifera L. cvs Shiraz and Cabernet Sauvignon was either unaltered or increased in response to PRD over two seasons. Where an increase in anthocyanin concentration was found with PRD, this was found to be independent of berry size. Rather, increases in anthocyanin concentration were most likely due to an increase in anthocyanin production in the berry skins. In Cabemet Sauvignon wine made from one vintage, total colour was enhanced by 10% in response to the PRD treatment, although in that season total anthocyanin concentration was unaltered in the fruit or wine. This colour enhancement was due to an increase in coloured pigments in copigmented or polymeric form, that is in association with other anthocyanins or phenolic compounds. This is a significant finding, as it shows that the colour of wine is not dependent upon anthocyanin concentration alone, but rather on reactions taking place during winemaking and wine-ageing. The colour enhancement was found to be maintained after a year's ageing in the bottle. A key question which arises from this work is which component(s) of total phenolics in PRD-treated wines is responsible for this effect. Preliminary investigation of seed proanthocyanidins and flavan-3-ols showed that their content per berry was unaltered by the PRD treatment. However, where berry weight was decreased due to PRD, the concentration of these seed tannins was increased on a per gram basis. This could potentially lead to an increased contribution of seed tannins to total wine phenolics in PRD wines. The effect of this is two-fold. Firstly, seed tannins are known to be weak copigments and could in part account for the increased copigmentation and polymerisation of anthocyanins observed with PRD. Secondly, an increased concentration of seed tannins in PRD wines could alter wine astringency and mouth feel properties. In both fruit and wine samples, PRD was found to cause a decrease in the contribution malvidin-glucosides to total anthocyanins. Thus, levels of non-malvidin glucosides, namely delphinidin and cyanidin, were increased by PRD. This effect was investigated as fruit matured post-veraison, and was evident from early in berry development. Preliminary results indicate that this response requires the presence of high incident light levels to the fruit during development, but is not mediated by increased bunch exposure alone. Shading of fruit led to a significant decrease in all anthocyanin types, and caused a shift in the ratio of acetyl- and 3p-coumary1-glucosides to mono-glucosides. The PRD treatment, however, did not cause changes in the proportions of acetyl-, 3p-coumary1-and mono-glucoside anthocyanins. These results show that the response of the anthocyanin pathway to the PRD treatment is most likely mediated by physiological signals within the fruit and vine, rather than due to a change in bunch zone microclimate. An important class of potential flavour and aroma compounds in grapes are the C₁₃-norisoprcnoids. As the precursors to these compounds are fruit-derived, rather than by-products of fermentation, the potential exists for their manipulation using viticultural practices. Previously, bunch exposure has been thought to be the primary factor mediating the final levels of C₁₃-norisoprenoids in fruit. The current study has shown that total shading of developing bunches using artificial means led to a significant decrease in the levels of these compounds in both fruit and wine samples of Shiraz. However, when fruit of this variety was subjected to natural changes in bunch exposure, resulting from alterations in canopy structure, the response of the C₁₃-norisoprenoids to these conditions was either small or insignificant. Of the three C₁₃-norisoprenoids studied, namely ß -damascenone, ß -ionone and TDN, only TDN showed a significant response to bunch exposure under these conditions. Preliminary results of this study on Shiraz indicated that the concentration of the C₁₃-norisoprenoids ß -damascenone and TDN can potentially be influenced by changes in vine shoot vigour and canopy architecture, induced by a water-deficit. This finding was validated by a study on Cabernet Sauvignon, where the effect of PRD on fruit C₁₃-norisoprenoids was investigated. The concentrations of the C₁₃-norisoprenoids ß -damascenone, ß -ionone and TDN were shown to be increased by up to 30% in response to PRD in Cabernet Sauvignon fruit over two vintages. The changes in these compounds in the fruit were associated with increased levels of the carotenoids lutein and ß -carotene, which are potential precursors to the C₁₃-norisoprenoids. The results of the current study have shown that the regulation of C₁₃- norisoprenoid concentration in grapes and wine may not be primarily due to the level of incident light on developing bunches, although the presence of light is necessary for their production. Rather, the effect of deficit irrigation practices on whole-vine physiology and vine shoot vigour holds stronger potential as a tool for the viticultural manipulation of these compounds in fruit and wine. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1129092 / Thesis (Ph.D.) -- University of Adelaide, School of Wine and Agriculture, 2004

Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The effect of partial rootzone drying (PRD) on the composition of grape and wine secondary metabolites was investigated. At harvest, total anthocyanin and phenolic concentration in fruit of Vitis vinifera L. cvs Shiraz and Cabernet Sauvignon was either unaltered or increased in response to PRD over two seasons. Where an increase in anthocyanin concentration was found with PRD, this was found to be independent of berry size. Rather, increases in anthocyanin concentration were most likely due to an increase in anthocyanin production in the berry skins. In Cabemet Sauvignon wine made from one vintage, total colour was enhanced by 10% in response to the PRD treatment, although in that season total anthocyanin concentration was unaltered in the fruit or wine. This colour enhancement was due to an increase in coloured pigments in copigmented or polymeric form, that is in association with other anthocyanins or phenolic compounds. This is a significant finding, as it shows that the colour of wine is not dependent upon anthocyanin concentration alone, but rather on reactions taking place during winemaking and wine-ageing. The colour enhancement was found to be maintained after a year's ageing in the bottle. A key question which arises from this work is which component(s) of total phenolics in PRD-treated wines is responsible for this effect. Preliminary investigation of seed proanthocyanidins and flavan-3-ols showed that their content per berry was unaltered by the PRD treatment. However, where berry weight was decreased due to PRD, the concentration of these seed tannins was increased on a per gram basis. This could potentially lead to an increased contribution of seed tannins to total wine phenolics in PRD wines. The effect of this is two-fold. Firstly, seed tannins are known to be weak copigments and could in part account for the increased copigmentation and polymerisation of anthocyanins observed with PRD. Secondly, an increased concentration of seed tannins in PRD wines could alter wine astringency and mouth feel properties. In both fruit and wine samples, PRD was found to cause a decrease in the contribution malvidin-glucosides to total anthocyanins. Thus, levels of non-malvidin glucosides, namely delphinidin and cyanidin, were increased by PRD. This effect was investigated as fruit matured post-veraison, and was evident from early in berry development. Preliminary results indicate that this response requires the presence of high incident light levels to the fruit during development, but is not mediated by increased bunch exposure alone. Shading of fruit led to a significant decrease in all anthocyanin types, and caused a shift in the ratio of acetyl- and 3p-coumary1-glucosides to mono-glucosides. The PRD treatment, however, did not cause changes in the proportions of acetyl-, 3p-coumary1-and mono-glucoside anthocyanins. These results show that the response of the anthocyanin pathway to the PRD treatment is most likely mediated by physiological signals within the fruit and vine, rather than due to a change in bunch zone microclimate. An important class of potential flavour and aroma compounds in grapes are the C₁₃-norisoprcnoids. As the precursors to these compounds are fruit-derived, rather than by-products of fermentation, the potential exists for their manipulation using viticultural practices. Previously, bunch exposure has been thought to be the primary factor mediating the final levels of C₁₃-norisoprenoids in fruit. The current study has shown that total shading of developing bunches using artificial means led to a significant decrease in the levels of these compounds in both fruit and wine samples of Shiraz. However, when fruit of this variety was subjected to natural changes in bunch exposure, resulting from alterations in canopy structure, the response of the C₁₃-norisoprenoids to these conditions was either small or insignificant. Of the three C₁₃-norisoprenoids studied, namely ß -damascenone, ß -ionone and TDN, only TDN showed a significant response to bunch exposure under these conditions. Preliminary results of this study on Shiraz indicated that the concentration of the C₁₃-norisoprenoids ß -damascenone and TDN can potentially be influenced by changes in vine shoot vigour and canopy architecture, induced by a water-deficit. This finding was validated by a study on Cabernet Sauvignon, where the effect of PRD on fruit C₁₃-norisoprenoids was investigated. The concentrations of the C₁₃-norisoprenoids ß -damascenone, ß -ionone and TDN were shown to be increased by up to 30% in response to PRD in Cabernet Sauvignon fruit over two vintages. The changes in these compounds in the fruit were associated with increased levels of the carotenoids lutein and ß -carotene, which are potential precursors to the C₁₃-norisoprenoids. The results of the current study have shown that the regulation of C₁₃- norisoprenoid concentration in grapes and wine may not be primarily due to the level of incident light on developing bunches, although the presence of light is necessary for their production. Rather, the effect of deficit irrigation practices on whole-vine physiology and vine shoot vigour holds stronger potential as a tool for the viticultural manipulation of these compounds in fruit and wine. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1129092 / Thesis (Ph.D.) -- University of Adelaide, School of Wine and Agriculture, 2004

Landscape characteristics affect vineyard microclimates and influence the quality of grapes produced. There is currently a lack of research examining the microclimatological conditions of vineyards and how they affect grape quality. This study utilizes qualitative methods to explore the relationship between vineyard microclimates and grape quality in Madeira, Portugal. Semi-structured interviews have been conducted with local participants involved in the production of wine grapes and are used to reveal the factors affecting grape quality. Interviews accompany a physical inventory of landscape characteristics in the vineyards, and are guided by where interviewees observe changes in grape quality. The findings suggest there is a strong relationship between microclimates and grape quality. These results are utilized to make recommendations for methods of site selection and the microclimatic design of vineyards.

Orientador: Antonio Carlos de Oliveira Ferraz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-21T13:30:46Z (GMT). No. of bitstreams: 1 Gomes_Daniel_D.pdf: 16813107 bytes, checksum: fa39cbbc8ab31a99a84b439cf1130d71 (MD5) Previous issue date: 2012 / Resumo: A cultivar de uva Niagara Rosada é a principal uva de mesa brasileira e o Estado de São Paulo é seu maior produtor com cerca de 2000 propriedades vitícolas (OLIVEIRA et al. 2008). O seu cultivo está se expandindo, dentre os fatores responsáveis destacam-se: o menor custo de produção em relação ao cultivo de uvas finas; maior rusticidade e menor necessidade de defensivos agrícolas. Apesar dos 79 anos de existência desde sua identificação e das inúmeras vantagens no cultivo, a uva 'Niagara Rosada' possui pouquíssimos estudos sobre sua pós-colheita, maturação ideal na vindima e suas consequências na vida útil dos frutos, e de sua aceitação pelo consumidor. A uva é comercializada freqüentemente abaixo do índice de maturação de 14o Brix indo contra a legislação brasileira. É comercializada imatura, ou seja, pouco doce, ácida e verde, causando malefícios a toda cadeia. Os produtores costumam comercializá-la mesmo fora da legislação vigente argumentando que não suportariam o manuseio, acondicionamento e transporte caso fossem colhidas no estádio recomendado. Diante do exposto o objetivo desse trabalho foi investigar a variação da qualidade e da vida útil da uva 'Niagara Rosada' quando colhida em diferentes estádios de maturação. Estabelecer faixas de maturação que proporcionem maior vida útil e aceitação dos consumidores e questionar a validade do parâmetro de colheita 14o Brix da legislação brasileira com outro parâmetro a razão sólidos solúveis / acidez titulável, que leva em conta a palatabilidade humana. Para tais avaliações a principio foi realizada uma coleta de cachos de uva cobrindo amplo espectro de estádios de maturações, observando a data da poda, os estádios fenológicos de 33 a 38 (EICHORN e LORENZ, 1984) e classificando-os cachos em faixas de maturação de sólidos solúveis de 1%, resultando em nove faixas de maturação de 8 a 17o Brix. Dentro deste amplo espectro de maturações os cachos foram analisadas utilizando-se a razão sólidos solúveis / acidez titulável, o que resultou na escolha três faixas de maturações 12, 14 e 16o Brix que posteriormente foram utilizadas para investigar a variação nos principais atributos qualitativos da uva 'Niagara Rosada' e em sua aceitação pelo consumidor. Para avaliação da qualidade e vida útil foi utilizado a, incidência de doenças, perda de massa, aparência do engaço, degrana, avaliação manual da rigidez dos cachos, vitamina C, taxa respiratória, firmeza e força de destacamento das bagas. Nas avaliações de aceitação e intenção de compra pelos consumidores incluíram-se também cachos na faixa de 10o Brix considerados imaturos neste trabalho, mas presentes na comercio, com intenção de avaliar a percepção do consumidor sobre esta faixa de maturação. A análise sensorial incluiu a faixa etária dos consumidores, aceitabilidade quanto à aparência, sabor, intensidade ideal do gosto doce e ácido e intenção de compra dos frutos nos diversos estádios de maturação. Não houve diferença nas faixas de maturação consideradas quanto aos indicadores temporais de qualidade, perda de massa, aparência do engaço, degrana, teor vitamina C e a taxa respiratória, porem influenciaram na incidência de doença e rigidez dos cachos, firmeza e força de destacamento das bagas. Durante o armazenamento todos os indicadores temporais de qualidade apresentaram variações, mas nem todos foram capazes de oferecer limites que pudessem ser utilizados como parâmetro de vida útil dos frutos. A vida útil foi avaliada sendo utilizada a perda de massa, aparência do engaço, degrana e rigidez do cacho; parâmetros que possibilitaram estabelecer limites claros de qualidade admissível a um cacho de uva e sua vida útil avaliada em 6,5, 6,75 e 8,5 dias para cachos com 16, 14 e 12o Brix. A cor da fruta foi seu principal atrativo aos consumidores, seguido de preço e tamanho do cacho. Em relação à aparência e a coloração dos cachos, os mais maduros foram os preferidos, porém, os consumidores não conseguiram discriminar ou simplesmente aceitaram a aparência e cor de cachos verdes com 10º Brix da mesma forma que os de 12º Brix, verificaram-se que a degrana de 5% é admitida pelos provados corroborando com determinações da Lei de padronização vigente, já a presença de bagas rompidas não foi admitida. Em relação ao sabor, cachos com 10º Brix (verdes) foram rejeitados quanto mais madura a uva, maior sua aceitação. A uva Niagara Rosada foi considerada pouco doce pelo consumidor e bem aceitas relação à acidez Quanto à avaliação de intenção de compra todas as maturações menos a de 10º Brix foram bem aceitas. Conclui-se que a uva 'Niagara Rosada' é adequada ao consumo nas faixas de 12, 14 e 16o Brix, contemplando a faixa de 12o Brix banida pela legislação brasileira. Conclui-se que acima de 16 Brix encontram-se em sobrematuração e impróprias para consumo 'in natura'. Conclui-se também que o parâmetro sólidos solúveis é inadequado para determinação da maturação. Uvas com 12o Brix obtiveram vida útil 22% maior que as faixas de 14 e 16o Brix que foram estatisticamente semelhantes. Conclui-se nas avaliações sensoriais que cachos na faixa dos 12 o Brix possuem poça rejeição pelo consumidor corroborando com as praticas comerciais correntes e que cachos com 14 e 16o Brix foram muito bem aceitos / Abstract: 'Niagara Rosada' is the main Brazilian table grape. The state of Sao Paulo is its largest producer with about 2000 vineyards (Oliveira et al. 2008). The cultivation of 'Niagara Rosada' is expanding because the low cost of production as compared to fine grapes, rusticity and less demands for agrochemicals. Despite 79 years of existence and those many cultivating advantages, 'Niagara Rosada' has very few post-harvest investigations in topics such as harvest time and its effect on shelf life, and consumer acceptance. The grape is often traded below the rate of maturation of the 14o Brix established by Brazilian legislation, and often, also sold immature, with little sugar content, high acidity, causing harm to all elements of the productivity chain. Producers are used to commercialize them even against legislation arguing the produce would not resist handling, packaging and transport if harvested in the recommended harvested stage. Given the above and to respond to qualitative variation of the main attributes of 'Niagara Rosada' in different degrees of maturation, this study aimed to investigate the variation in quality and service life of 'Niagara Rosada' when harvested in different stages f maturity. From these considerations the objectives of this work was to investigate the quality variation of 'Niagara Rosada' grapes harvested in different maturity, to establish the maturity stage with longer shelf life and consumer acceptance, and to contrast the current legislation that uses soluble solids to define a harvest stage against sugar acid rate, wich includes human perception. Initially, for those evaluations, clusters were harvested covering a wide maturity range, taking into consideration pruning date, phenological stage between 33 and 38, and classifying them according to soluble solids values ,within 1% variation, resulting in 9 maturity classes ranging from 8 to 17o Brix. Within this wide range, clusters were analyzed using sugar acid rate resulting in 3 maturation classes, 12, 14 and 16o Brix that further were used for quality and sensorial evaluation. Disease occurrence, mass loss, stem appearance, berry drop, cluster stiffness, vitamin C content, respiration rate, berry firmness and detachment force. For acceptance and consumer perception evaluation clusters having soluble solids values as low as 10o Brix were used. These analyses also included age group, appearance, flavor, acceptance, acidity and sugar taste intensity and buying intention of the 'Niagara Rosada' grape at different maturity stages. No difference was observed in the quality parameters such as mass loss, stem appearance, berry drop, vitamin C content and respiration rate among the considered maturity stages. However, maturity stages did influence disease occurrence, cluster stiffness, berry firmness and detachment force. During storage all temporal quality indicators showed variation, but not all of them could be used to determine shelf life. The ones used, then, were mass loss, stem appearance, berry drop and cluster stiffness that showed clear limits for admissible quality. Shelf life was identified as 6.5, 6.75, and 8.5 days corresponding to soluble solids values of 16, 14 and 12o Brix, respectively. Fruit color was the main acceptance criteria for consumers, followed by price and cluster size. As far as cluster appearance and color are concerned, the ripest ones were preferred. The sensorial panel was not able to differentiate maturity at 10 and 12o Brix maturity stages; berry drop up to 5% was accepted, supporting current legislation, but busted berries were not. Riper clusters were preferred. 'Niagara Rosada' was considered of little sugar content by the consumer and ideal concerning acidity. Buying intention included all maturity stages except the 10o Brix one. It was concluded that 'Niagara Rosada' grape is adequate for consumption when in the 12, 14 and 16o Brix maturity stages, which includes the 12o Brix stage, not accepted by current Brazilian legislation. It was concluded that above 16o Brix clusters are overripe and , therefore, not suitable for consumption. It was also concluded that soluble solids values are not suitable for maturity stage determination. Grapes with 12o B showed a 22 % greater shelf live than the other two considered maturity stages. Finally, it was concluded that 12o Brix cluster showed little rejection, supporting usual commercial practices. Clusters with 14 and 16o Brix were the most accepted / Doutorado / Tecnologia Pós-Colheita / Doutor em Engenharia Agrícola

Thesis (MScAgric)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The two white seedless table grape cultivars, Regal Seedless and Thompson Seedless fulfil a very important role in securing foreign income not only for the South African table grape industry, but the South African economy as a whole. These two cultivars, however, are like so many other white table grape cultivars, also prone to browning, especially netlike browning on Regal Seedless and internal browning on Thompson Seedless grapes. This leads to huge financial losses every year, since there is no established way to assess at harvest, during storage or during packaging, whether the grapes will eventually turn brown. In other words, there is no well-known protocol of assessing the browning risk of a particular batch of grapes prior to export. Numerous studies have been undertaken to determine the exact cause of browning and how it should be managed, but to date, no chemical or physical parameter has been firmly associated with the phenomenon. The overall aim of this study was thus to find an alternative way to deal with the problem by investigating the potential of near infrared (NIR) spectroscopy as a fast, non-destructive measurement technique to determine the browning potential of whole white seedless table grapes. A secondary aim was the determination of optimal ripeness of table grapes. In this way harvest maturity and quality indicative parameters namely total soluble solids (TSS), titratable acidity (TA), pH, glucose and fructose, also associated with the browning phenomenon, was quantified using models based on infrared spectra. Three different techniques (a) Fourier transform Near Infrared (FT-NIR), (b) Fourier transform – Mid Infrared (FT-MIR) and (c) Fourier transform – Mid Infrared Attenuated Total Reflectance (FT-MIR ATR) spectroscopy were investigated to determine these parameters. This was done so that a platform of different technologies would be available to the table grape industry. The grapes used in this study were harvested over two years (2008 and 2009) and were sourced from two different commercial vineyards in the Hex River valley, Western Cape, South Africa. Different crop loads (the total amount of bunches on the vines per hectare) were left for Regal Seedless (75 000, 50 000 and 35 000) and for Thompson Seedless (75 000 and 50 000). Three rows were used for Regal Seedless and two rows for Thompson Seedless. Each row had six sections which each represented a repetition for each crop load. In 2008 these cultivars were harvested early at 16°Brix, at optimum ripeness (18°Brix) and late at 20°Brix. In 2009 they were harvested twice at the optimum ripeness level. Berries from harvested bunches were crushed and the juice was used to determine the reference values for the different parameters in the laboratory according to their specific methods. The obtained juice was also scanned on the three different instruments. Different software (OPUS 6.5 for the FT-NIR and FT-MIR ATR instruments and Unscrambler version 9.2 for the FT-MIR instrument) as well as different spectral pre-processing techniques were also evaluated before construction of the models for all the instruments. Partial least squares (PLS) regression was used for the construction of the different calibration models. Different regression statistics, that included the root mean square error for prediction (RMSEP); the coefficient of determination (R2); the residual prediction deviation (RPD) and the bias were used to evaluate the performance of the developed calibration models. Calibration models which are fit for screening purposes were obtained on the FT-NIR and FTMIR ATR instruments for TSS (11.40 - 21.80°Brix) (R2 = 85.92%, RMSEP = 0.71 °Brix RPD = 2.67 and bias = 0.03°Brix), pH (2.94 - 3.9) (R2 = 85.00%, RMSEP = 0.08 RPD = 2.59 and bias = -0.01) and TA (4.3 - 13.1 g/L), (R2 = 90.77%, RMSEP = 0.48 g/L RPD = 3.30 and bias = -0.03 g/L). Models for fructose (46.70 – 176.82 g/L) (R2 = 74.66%, RMSEP = 9.28 g/L RPD = 2.00 and bias = 1.10 g/L) and glucose (20.36 – 386.67 g/L) (R2 = 70.71%, RMSEP = 11.10 g/L RPD = 1.87 and bias = 1.64 g/L) were obtained with the FT-NIR and FT-MIR ATR instruments that were in some instances fit for screening purposes and in some instances unsuitable for quantification purposes. The FT-MIR instrument gave models for all the parameters that were not yet suitable for quantification purposes. Combined spectral ranges used for calibration were often similar for some parameters, namely 12 493 - 5 446.2 for TSS and pH, 6 101.9 - 5 446.2 for TSS, TA and fructose and 4 601.5 - 4 246.7 for pH and fructose on the FT-NIR instrument, 2 993.2 - 2 322.3 for pH, TA and glucose and 1 654.3 - 649.4 for pH and glucose on the FT-MIR ATR instrument and sometimes they were adjacent (3 996.6 - 3 661.2, 3 663.5 - 3 327.7 and 3 327.2 - 2 322.3 for TSS and glucose, 1 988.3 - 1 652.8 and 1 654.3 - 649.4 for TSS, pH and TA. Other times they were overlapping (1 654.3 - 649.4 and 1 318.8 - 649.4) for pH, TA and fructose on the FT-MIR ATR instrument. This is a very good sign for transfer of this technology to a handheld device, where adjacent and/ or overlapping wavenumbers are crucial. Instruments which have to determine different parameters over large spectral ranges are not only impractical, because the instrument has to be big, but because it is also very expensive. Another advantage of implementing especially FT-NIR spectroscopy as a fast, accurate and inexpensive technique for determining harvest maturity and quality parameters is because no sample preparation is necessary and very little waste (few single berries tested) is produced. This is a pre-requisite which is highly recommended in the green era that we are currently living in and will do so for aeons to come. A platform of technologies has now been made available through this study for the determination of the respective parameters in future table grape samples by just taking their spectra on one of the instruments. Indeed something that has not been possible or available for the South African table grape industry before. Berries for the browning experiments were scanned on a FT-NIR instrument immediately after harvest (before cold storage) and again after cold storage. Before cold storage they were scanned on each side of the berry and after cold storage they were scanned twice on a brown spot if browning was present and twice on a clear spot, irrespective of whether browning was present or not. Inspection of the berries for the incidence of browning after cold storage revealed that Regal Seedless had a higher incidence of browning (68% in 2008 and 66% in 2009) than Thompson Seedless (21% in 2008 and 25% in 2009). Regal Seedless was also more prone to external browning, specifically netlike browning, whereas Thompson Seedless was more prone to internal browning, despite the different phenotypes of browning that were present on both. Principal component analysis (PCA) done on the spectra obtained before and after cold storage revealed that NIR can capture the changes related to cold storage with the first principal components explaining almost 100% of the variation in the spectra. Classification models also build using PCA was based on spectra of berries that remained clear before and after cold storage and those that turned brown after cold storage. Classification models of berries based on spectra obtained after cold storage (browning present) had a better total accuracy (94% for training- and 87% for test datasets), than the classification models based on spectra obtained before cold storage (79% for training- and 64% for test datasets). The implication of this is that the current models will be able to classify berries in terms of those which have turned brown already and those that remained clear better after cold storage than before cold storage, which is the critical stage where we want to actually know whether the berries will turn brown or not. The potential, however, to use NIR spectroscopy to detect browning before harvest already on white seedless grapes is still present, since all these models were built using the whole NIR spectrum. No variable selection was thus done and all the different browning phenotypes were also used together. Further analysis of the data will thus be based on using variable selection techniques like particle swarm optimization (PSO) to select certain wavelengths strongly associated with the browning phenomenon and only on the main types of browning (netlike on Regal Seedless and internal browning on Thompson Seedless). This study has major implications for the table grape industry, since it is the first time that the possibility to predict browning with other methods than visual inspection, especially before cold storage, is shown. / AFRIKAANSE OPSOMMING: Die twee wit pitlose tafeldruif kultivars, Regal Seedless en Thompson Seedless onderskeidelik, speel 'n baie belangrike rol in die verkryging van buitelandse inkomste, nie net vir die Suid- Afrikaanse tafeldruif industrie nie, maar ook vir die Suid-Afrikaanse ekonomie as 'n geheel. Hierdie twee kultivars is egter, soos baie ander wit kultivars, ook geneig tot verbruining. Dit is veral netagtige verbruining op Regal Seedless en interne verbruining op Thompson Seedless wat pertinent is. Hierdie belangrike kwaliteitsprobleme lei jaarliks tot groot finansiële verliese, aangesien daar huidiglik geen gevestigde prosedure is om voor oes, tydens opberging of tydens verpakking te bepaal of die druiwe uiteindelik gaan verbruin nie. Met ander woorde, daar is geen gevestigde protokol vir die beoordeling van die verbruinings risiko van 'n bepaalde groep druiwe voor dit uitgevoer word nie. Talle studies is alreeds onderneem om vas te stel wat die presiese oorsaak van hierdie verskynsel is en hoe dit bestuur moet word, maar geen enkele aspek wat bestudeer is kon tot op hede, herhaaldelik ge-assosieer word met die presiese oorsaak van verbruining nie. Die oorkoepelende doel van hierdie studie was dus om 'n alternatiewe manier te kry om hierdie probleem aan te spreek. ‘n Ondersoek na die potensiaal van naby infrarooi (NIR) spektroskopie as 'n vinnige en nie-vernietigende metings tegniek om die verbruinings potensiaal van ‘n wit pitlose tafeldruifkorrel wat nog heel is te bepaal, is onderneem. 'n Sekondêre doel was om die bepaling van optimale rypheid van tafeldruiwe te onderosek. Op hierdie manier is oesrypheid, en die kwaliteitsfaktore, naamlik totale oplosbare vastestowwe (TOVS), titreerbare suur (TS), pH, glukose en fruktose, wat ook gekoppel word aan die voorkoms van verbruining, deur middel van infrarooi (IR) spektroskopie modelle gekwantifiseer. Drie verskillende infrarooi metodes naamlik (a) die Fourier transform naby infrarooi (FT-NIR), (b) Fourier transform - Mid Infrarooi (FT-MIR) en (c) Fourier transform - Mid Infrarooi Verswakte Totale Refleksie (FT-MIR VTR) spektroskopie is gebruik om die aspekte te bepaal. Dis gedoen sodat 'n platform van tegnologie beskikbaar sou wees vir die tafeldruif industrie. Die druiwe wat in hierdie studie gebruik is, is oor twee jaar (2008 en 2009) en van twee verskillende kommersiële wingerde in die Hexriviervallei, Wes-Kaap, Suid-Afrika ge-oes. Verskillende oesladings (die totale aantal trosse op die wingerdstokke per hektaar) is vir Regal Seedless (75 000, 50 000 en 35 000) en Thompson Seedless (75 000 en 50 000) gelaat. Daar is drie rye gebruik Regal Seedless en twee vir Thompson Seedless. Elke ry het ses vakkies gehad wat dan verteenwoordigend was van ‘n herhaling vir elke oeslading. In 2008 is hierdie kultivars by vroeë rypwording (16°Brix), by optimale rypheid (18°Brix) en by laat rypheid (20°Brix) geoes. In 2009 is dit twee keer by die optimale rypheidsgraad geoes. Vir die bepaling van oesrypheid, en die kwaliteitsapekte is verskillende sagteware (OPUS 6.5 op die FT-NIR en FT-MIR VTR instrumente en Unscrambler weergawe 9.2 vir die FT-MIR instrument) sowel as verskillende spektrale voor-verwerking tegnieke ëvalueer voor die konstruksie van die kalibrasie modelle op die verskillende instrumente. Parsiële kleinste kwadraat (PKK) regressie is gebruik vir die opstel van kalibrasiemodelle vir die bepaling van laasgenoemde aspekte. Verskillende statistieke gegewens is gebruik om die kalibrasie modelle te evalueer, naamlik die bepalingskoëffisiënt (R2), die vierkantswortelgemiddelde- kwadraat fout vir voorspelling (VGKV), relatiewe voorspellingsafwyking (RVA) en sydigheid. Kalibrasie modelle wat geskik is vir keuring is verkry op die FT-NIR en FT-MIR VTR instrumente vir TOVS (11.40 – 21.80°Brix) (R2 = 85.92%, VGKV = 0.71°Brix, RVA = 2.67 en sydigheid = 0.03°Brix), pH (2.94 – 3.9) (R2 = 85.00%, VGKV = 0.08 g/L, RVA = 2.59 en sydigheid = -0.01 g/L), en TS (4.3 – 13.1 g/L), (R2 = 90.77%, VGKV = 0.48 g/L RVA = 3.30 en sydigheid = -0.03 g/L). Modelle vir fruktose (46.70-176.82 g/L) (R2 = 74.66%, VGKV = 9.28 g/L RVA = 2.00 en sydigheid = 1.10 g/L) en glukose (20.36 – 386.67 g/L) (R2 = 70.71%, VGKV = 11.10 g/L RVA = 1.87 en sydigheid = 1.64 g/L) is verkry met die FT-NIR en FT-MIR VTR instrumente wat in sommige gevalle gepas was vir keuringsdoeleindes en in sommige gevalle nie geskik was vir kwantifiserings doeleindes nie. Die FT-MIR-instrument het modelle vir al die aspekte gegee wat nog nie vir kwantifiserings doeleindes of vir keuringsdoeleindes geskik was nie. Gekombineerde spektrale reekse is gebruik vir die kalibrasies wat dikwels soortgelyk was vir sommige aspekte naamlik 12 493 - 5 446.2 vir TOVS en pH, 6 101.9 - 5 446,2 vir TOVS, TS en fruktose en 4 601.5 - 4 246.7 vir pH en fruktose op die FT-NIR instrument, 2 993.2 - 2 322.3 vir pH, TA en glukose en 1 654.3 – 649.4 vir pH en glukose op die FT-MIR VTR instrument. Andersyds, was dit aangrensend (3 996.6 - 3 661.2, 3 663.5 - 3 327.7 en 3 327.2 - 2 322.3) vir TOVS en glukose, 1 988.3 - 1 652.8, 1 654.3 – 649.4 vir TOVS, pH en TS en ander tye was dit weer oorvleuelend 1 654.3 – 649.4 en 1 318.8 – 649.4 vir pH, TS en fruktose op die FT-MIR VTR instrument. Dit is 'n baie goeie teken vir die oordrag van hierdie tegnologie na ‘n handgedraagde instrument, waar aanliggende en/of oorvleuelende golfnommers noodsaaklik is. Instrumente wat verskillende aspekte oor groot spektrale reekse moet bepaal is nie net onprakties, omdat die instrument groot moet wees nie, maar dit is ook baie duur. Nog 'n voordeel van die implementering van veral FT-NIR spektroskopie as 'n vinnige, akkurate en goedkoop tegniek vir die bepaling van oesrypheid, en die kwaliteit aspekte van druiwe is omdat daar geen monster voorbereiding nodig is nie en baie min afval (paar enkele korrels word gemonster) geproduseer word. 'n Voorvereiste wat sterk aanbeveel kom in die groen era waarin ons tans leef en nog vir eeue van nou af gaan doen. ‘n Platform van tegnologie is nou beskikbaar gestel deur middel van hierdie studie vir die bepaling van die onderskeie aspekte in toekomstige tafeldruif monsters deur net op een van die instrumente hulle spektra te neem. Inderdaad iets wat nie voorheen moontlik of beskikbaar was vir die Suid- Afrikaanse tafeldruif industrie nie. Korrels vir die verbruiningseksperimente is geskandeer direk na oes (voor koelopberging) en weer na koelopberging. Dit was voor koelopberging op elke kant van die korrel skandeer en na koelopberging was dit twee maal skandeer op 'n bruin vlek indien verbruining teenwoordig was en twee keer op 'n helder plek, ongeag of verbruining teenwoordig was of nie. Inspeksie van die korrels vir die voorkoms van verbruining na koelopberging het aan die lig gebring dat Regal Seedless 'n hoër voorkoms van verbruining (68% in 2008 en 66% in 2009) as Thompson Seedless (21% in 2008 en 25% in 2009) gehad het. Regal Seedless was ook meer geneig om eksterne verbruining, spesifiek netagtige verbruining te vertoon, terwyl Thompson Seedless meer geneig was om interne verbruining te vertoon, ten spyte van die verskillende fenotipes van verbruining wat teenwoordig was op beide kultivars. Hoofkomponente analise (HKA) is op die spektra gedoen voor en na koelopberging en naby infrarooi spektroskopie het aan die lig gebring dat die veranderinge wat verband hou met koelopberging met die eerste hoofkomponent (HK) verduidelik kan word met byna 100% van die variasie in die spektra wat daarin vasgevang is. Klassifikasiemodelle is ook deur die gebruik van HKA gebou en was gebaseer op die spektra van korrels wat vekry is voor en na koelopberging asook die wat verkry is nadat korrels verbruin het na koelopberging. Klassifikasiemodelle van korrels wat gebaseer was op spektra na koelopberging (verbruining teenwoordig) het 'n beter algehele akkuraatheid (94% vir opleidingsdata en 87% vir toetsdata), getoon as die klassifikasiemodelle wat gebaseer was op spektra van korrels voor koelopberging (79% vir opleidings data en 64% vir toetsdata). Die implikasie hiervan is dat die huidige modelle in staat sal wees om korrels beter te klassifiseer in terme van diegene wat alreeds verbruin het en die wat nie verbruin het na koelopberging as daardie voor koelopberging, wat juis die kritieke stadium is waar ons wil weet of die korrels wel gaan verbruin of nie. Daar is wel potensiaal wat verder ontgin kan word, aangesien al hierdie modelle gebou is deur gebruik te maak van die hele NIR spektrum. Geen veranderlike seleksie is dus gedoen nie en al die verskillende verbruiningsfenotipes is ook saam gebruik in die opstel van die modelle. Verdere analise van die data sal dus gebaseer word op die gebruik van veranderlike seleksie tegnieke soos deeltjie swerm optimisasie (DSO) wat sekere golflengtes kies wat sterk verband hou met die verbruining verskynsel en slegs die belangrikste tipes van verbruining (netagtig op Regal Seedless en interne verbruining op Thompson Seedless) sal gebruik word. Hierdie studie het 'n baie belangrike implikasie vir die tafeldruifbedryf, want dit is die eerste keer dat die moontlikheid om verbruining te voorspel met ander metodes as visuele inspeksie, veral voor koelopberging, getoon word. / The Postharvest and Innovation Programme, for financing this study

Orientadores: Marcelo Alexandre Prado, Marta Cristina Teixeira Duarte / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T16:17:17Z (GMT). No. of bitstreams: 1 PellissonPereira_Joyce_M.pdf: 5978783 bytes, checksum: 8f2e7c4beeb8f92b272e24c19ca8614e (MD5) Previous issue date: 2011 / Resumo: A uva Máximo IAC 138-22 apresenta boas características para a produção de vinho com elevado grau Brix. Durante a vinificação, os compostos fenólicos presentes nas uvas são extraídos para o mosto e são de fundamental importância para as características organolépticas do vinho, além de propriedades antioxidantes, antimicrobianas, anticarcinogênicas, anti-inflamatórias, diuréticas, tranquilizantes, antidiabéticas. Dentre estas propriedades, destacam-se a antioxidante e a antimicrobiana, visto que há um interesse emergente no uso de antioxidantes naturais em substituição aos sintéticos visando à preservação de alimentos, além de o seu consumo ser associado à proteção contra doenças severas, que envolvem danos por radicais livres. Além de prevenir a oxidação dos alimentos, os fenólicos poderiam reduzir a deterioração por micro-organismos, visto que apresentam atividade contra bactérias Gram (+), Gram (-) e leveduras. Neste trabalho foram avaliados extratos obtidos em etanol e em acetona de uva Máximo IAC 138-22, casca, polpa e semente, três estágios da vinificação, dois resíduos do processamento do vinho e o vinho artesanal obtido neste processo. Foram avaliados o conteúdo de fenólicos totais, a atividade antioxidante e a concentração mínima inibitória (MIC) dos extratos. Não foi verificada diferença significativa entre as extrações em relação à atividade antioxidante, exceto para a semente e o primeiro resíduo da vinificação. As amostras que apresentaram os maiores teores de fenólicos e também fortes a moderadas atividades antioxidantes definidas pelo AAI foram as sementes (semente em etanol: 136,40 mg de EAG/g de extrato e AAI de 1,717), os resíduos (2º resíduo em acetona: 78,47 mg de EAG/g de extrato e AAI de 0,912) e as cascas (casca em acetona: 58,79 mg de EAG/g de extrato e AAI de 0,546), sugerindo o potencial de reaproveitamento dos resíduos como antioxidantes em substituição aos sintéticos. Em relação à atividade antimicrobiana, os Gram (+) foram mais sensíveis que os Gram (-). Destaque para a bactéria B. cereus, que foi o micro-organismo mais sensível, e para a levedura C. albicans, que foi inibida pelos extratos de sementes a baixas concentrações (valores de MIC de 0,001 mg/mL e 0,002 mg/mL). P. aeruginosa foi inibida apenas por alguns extratos do processamento do vinho, o que pode estar relacionado à formação de fenólicos durante a vinificação. O vinho apresentou atividade antimicrobiana contra todas as bactérias Gram (+) e Gram (-) avaliadas e os resíduos da vinificação apresentaram elevados teor de fenólicos e atividade antimicrobiana, com valores de MIC de 1,5 mg/mL a >10 mg/mL), o que sugere a possibilidade de seu reaproveitamento / Abstract: Máximo IAC 138-22 grape has good characteristics for production of wine with a high Brix degree. During winemaking, phenolics compounds in grapes are extracted into the must and they are of fundamental importance for organoleptic characteristics of wine, as well as antioxidant, antimicrobial, anticarcinogenic, anti-inflammatory, diuretics, tranquilizers, anti-diabetic properties. Among these properties, antioxidant and antimicrobial are featured, since there is an emerging interest in the use of natural antioxidants to replace synthetic materials in order to preserve food, besides their use is associated with protection against severe disease involving damage by free radicals. In addition to preventing the oxidation of food, phenolics could prevent deterioration by microrganisms, due to their activity against Gram (+), Gram (-) and yeast. In this work, it was evaluated extracts in ethanol and acetone of Máximo IAC 138-22 grape, skin, pulp and seed, three stages of winemaking, two wastes and wine obtained from this process. It was evaluated the total phenolic content, antioxidant activity and the minimum inhibitory concentration (MIC) of extracts. There was no significant difference between two extractions for most of the samples, except seed and the first waste of winemaking. Samples that showed the highest levels of phenolics and also strong to moderate antioxidant activities, defined by AAI, were seeds (seed in ethanol: 136,40 mg of EAG/g of extract and AAI of 1,717), wastes (2º waste in acetone: 78,47 mg of EAG/g of extract and AAI of 0,912) and skin (skin in acetone: 58,79 mg of EAG/g of extract and AAI of 0,546), suggesting a potential for recycling waste to replace synthetic antioxidants. About antimicrobial activity, Gram (+) were more sensitive than Gram (-). Featured to B. cereus, that was the most sensitive microrganism, and yeast C. albicans, that was inhibited by seed extracts at low concentrations (MIC values of 0.001 mg/mL and 0.002 mg/mL). P. aeruginosa was inhibited only by some extracts from winemaking, which may be related to phenolics compounds produced during this process. Wine showed antimicrobial activity against all Gram (+) and Gram (-) and wastes showed a high phenolic content and antimicrobial activity, with MIC values of 1.5 mg/mL to >10 mg/mL), suggesting the possibility of its reuse / Mestrado / Ciência de Alimentos / Mestre em Ciência de Alimentos

Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest. Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms. The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests. Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2015-03-20T19:07:47Z No. of bitstreams: 2 Dissertação - Luiz Fernandes Cardoso Campos - 2014.pdf: 2505526 bytes, checksum: 7ebac4e791d989df7568c994b4f24d18 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2015-03-20T19:09:20Z (GMT) No. of bitstreams: 2 Dissertação - Luiz Fernandes Cardoso Campos - 2014.pdf: 2505526 bytes, checksum: 7ebac4e791d989df7568c994b4f24d18 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-03-20T19:09:20Z (GMT). No. of bitstreams: 2 Dissertação - Luiz Fernandes Cardoso Campos - 2014.pdf: 2505526 bytes, checksum: 7ebac4e791d989df7568c994b4f24d18 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-02-26 / The cultivation of the vine in the State of Goiás is already a reality and has good growth prospects, but there is little information about soil management, particularly regarding the use of cover crops in the vineyards soil. The use of management techniques aimed at improving the production system, accordingly the proper management of soil and vine canopy can influence yield and quality of grape. Therefore the objective of this study was to evaluate the development, the rate of decomposition and accumulation of nutrients in the shoots of ground cover grown intercropped with vine, besides the chemical characteristics of the soil and the nutritional status, growth and production of fruit species as well as the qualitative characteristics of the fruits. The experiment consisted of six treatments established in a randomized block design, in 3 x 2 factorial scheme, with five replicates. The first factor with three levels, was composed of the following plant species cover crops: bean-to-pig (Canavalia ensiformis L. DC), lab-lab (Dolichos lab lab L.) and weeds. The second factor, with two levels of pruning were carried out based on the seeding of cover crops. Ie, the first season pruning was done 25 days after sowing (DAS) of the cover crop and the second season of pruning performed at 55 DAS. Each plot of 9 m2 (2 x 4.5 m) contained two vine plants. Pruning times do not influence the rate of soil cover and biomass production by cover crops. The weeds provide the highest rates of soil cover. The bean-to-pig has higher production of plant biomass (dry and green). Plants have evaluated coverage rate similar decomposition, pruning times do not affect the decomposition of the cover crop. The fabaceae stand on the accumulation and release of nutrients, but it does not differ from wild plants, the change in the soil chemistry. Cover crops did not influence the nutritional status of the vine. The morphologic parameters of vine plants Isabel are not influenced by ground cover plants. Cover crops influence soil not the vine as productivity and related variables. Of pruning influencing productivity and related variables in vineyards. Qualitative characteristics of the grape plants are not affected by ground cover, pruning times can influence the composition of the wort. / O cultivo da videira no Estado de Goiás já é uma realidade e apresenta boas perspectivas de crescimento, porém são escassas as informações sobre o manejo do solo, principalmente quanto ao uso de plantas de cobertura do solo nos parreirais. O uso de técnicas de manejo visa à melhoria do sistema produtivo, nesse sentido o manejo adequado do solo e da copa da videira, podem influenciar a produção e a qualidade da uva. Portanto objetivou-se com este trabalho avaliar o desenvolvimento, a taxa de decomposição e o acúmulo de nutrientes pela parte aérea das plantas de cobertura do solo cultivadas em consórcio com videira, além das características químicas do solo e o estado nutricional, crescimento e a produção da espécie frutífera, bem como as características qualitativas dos frutos. O experimento consistiu em seis tratamentos estabelecidos em delineamento de blocos ao acaso, no esquema fatorial 3 x 2, em cinco repetições. O primeiro fator, com três níveis, foi composto pelas seguintes espécies de plantas cobertura do solo: feijão-de-porco (Canavalia ensiformis L. DC), lab-lab (Dolichos lab lab L.) e plantas espontâneas. O segundo fator, com dois níveis, foram épocas de poda, realizadas com base na semeadura das plantas de cobertura. Ou seja, a primeira época poda foi realizada 25 dias após a semeadura (DAS) das plantas de cobertura e a segunda época de poda realizada aos 55 DAS. Cada parcela de 9 m2 (2 x 4,5 m) continham duas plantas de videira. As épocas de poda não influenciam a taxa de cobertura do solo e produção de biomassa, pelas plantas de cobertura. As plantas espontâneas proporcionam as maiores taxas de cobertura do solo. O feijão-de-porco apresenta maiores produções de biomassa vegetal (seca e verde). As plantas de cobertura avaliadas apresentam de taxa decomposição similar, as épocas de poda não afetam a decomposição das plantas de cobertura. As fabaceas se destacam na acumulação e liberação dos nutrientes, porem não difere das plantas espontâneas, na alteração dos atributos químicos do solo. As plantas de cobertura não influenciam o estado nutricional da videira. As variáveis morfológicas das plantas de videira Isabel não são influenciadas pelas plantas de cobertura do solo. As plantas de cobertura do solo não influenciam a videira quanto a produtividade e as variáveis associadas. Diferentes épocas de poda influenciam a produtividade e as variáveis associadas na cultura da videira. As características qualitativas da uva não são influenciadas pelas plantas de cobertura do solo, as épocas de poda podem influenciar a composição do mosto.

Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest. Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms. The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests. Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.