The effects of crop load and berry exposure on the composition of Marlborough Sauvignon blanc grapes and wine from the Brancott vineyard, Blenheim, were explored. Commercially grown, 2-cane and 4-cane Sauvignon blanc vines were used with a row orientation of north-south. Two exposure treatments were imposed in the following manner: complete leaf removal was undertaken in the fruit zone and 50% shade cloth was erected to give a uniform shading treatment to half the trial vines. Weekly thirty-berry and whole bunch samples were taken from each of the 32 plots with the exception of the veraison period when two samples per week were taken. Vine vigour was assessed using pruning and leaf area per vine data. Harvest occurred on different dates for 2-cane and 4-cane pruned vines so that fruit attained from both treatments had similar °Brix. Fruit was processed at the Lincoln University winery. Must analysis and wine analysis were undertaken. As expected, 4-cane vines had almost double the yield of 2-cane vines. Higher crop load significantly reduced leaf area per shoot and shoot thickness. Lower leaf area to fruit ratio for 4-cane berries resulted in delayed onset of veraison and slowed the rate of sugar accumulation. Crop load, which limited leaf area to fruit ratio, appeared to be the dominant factor in determining timing of grape physiological ripeness as expressed by °Brix over other factors such as fruit exposure. Malic acid, tartaric acid, IPMP (iso-propylmethoxypyrazine) and IBMP (iso-butyl-methoxypyrazine) were lower at equivalent °Brix in 4-cane compared with 2-cane berries. Significantly higher concentrations of quercetin were found in exposed compared to shaded berries. Must analysis showed a significant influence of crop load on berry titratable acidity and pH, reflecting berry ripening results. Exposure significantly increased the concentrations of nitrogenous compounds in 4-cane must yet showed no influence on 2-cane must. After wine processing lower malic acid concentrations in wines made from 100% exposed fruit became evident in lower wine titratable acidity but showed no influence on wine pH. Bentonite addition to wines had a small but statistically significant influence on wine by reducing pH, titratable acidity and alcohol. Bound sulphur concentrations were significantly higher in 4-cane versus 2-cane wines. At harvest, methoxypyrazine levels in grapes and wines were very low; IBMP concentrations where significantly lower than those normally found in Sauvignon blanc wines from Marlborough. This was attributed to the absence of basal leaves from the shoots of ripening berries. The results suggest that leaf area to fruit ratio is a powerful determinant of grape and wine quality.

Electrical Impedance Spectroscopy (EIS) is a relatively new method applied to food quality assessment. EIS allows relatively inexpensive assessment, is fast, easy to operate and non-invasive. It has been adopted for investigation of fundamental electrical properties of plant tissues. Although the applications of EIS for food quality determination have been reported previously, the analytical relationships between electrical impedance properties and quality criteria have not yet been fully developed. Further exploration is thus important in acquiring more data on electrical impedance characteristics of fruits and vegetables and researching new approaches for determination of their quality. This dissertation aims to investigate the electrical impedance properties of fruits and vegetables, and explore the relationship between impedance and quality criteria. In particular, the present dissertation outlines experimental research conducted on relationships between impedance properties and fruit tastes as well as the impedance changes observed during ripening process. Impedance measurement to monitor moisture content changes in the progress of drying is also included in this research. In summary, the impedance properties have merits in fruits and vegetables quality assessment. The current used subjective visual inspection and assessment could be replaced by the EIS based approach as it is a more precise measurement of food quality. Further study is required to give this method practical value.

A novel non-destructive method of grape berry analysis is presented that uses reflected light to predict berry composition. The reflectance spectrum was collected using a diode array spectrometer (350 to 850 nm) over the 2009 and 2010 growing seasons. Partial least squares regression (PLS) and support vector machine regression (SVMR) generated calibrations between reflected light and composition for five berry components, total soluble solids (°Brix), titratable acidity (TA), pH, total phenols, and anthocyanins. Standard methods of analysis for the components were employed and characterized for error. Decomposition of the reflectance data was performed by principal component analysis (PCA) and independent component analysis (ICA). Regression models were constructed using 10x10 fold cross validated PLS and SVM models subject to smoothing, differentiation, and normalization pretreatments. All generated models were validated on the alternate season using two model selection strategies: minimum root mean squared error of prediction (RMSEP), and the "oneSE" heuristic. PCA/ICA decomposition demonstrated consistent features in the long VIS wavelengths and NIR region. The features are consistent across seasons. 2009 was generally more variable, possibly due to cold weather affects. RMSEP and R2 statistics of models indicate that PLS °Brix, pH, and TA models are well predicted for 2009 and 2010. SVM was marginally better. The R2 values of the PLS °Brix, pH, and TA models for 2009 and 2010 respectively were: 0.84, 0.58, 0.56 and: 0.89, 0.81, 0.58. 2010 °Brix models were suitable for rough screening. Optimal pretreatments were SG smoothing and relative normalization. Anthocyanins were well predicted in 2009, R2 0.65, but not in 2010, R2 0.15. Phenols were not well predicted in either year, R2 0.15-0.25. Validation demonstrated that °Brix, pH, and TA models from 2009 transferred to 2010 with fair results, R2 0.70, 0.72, 0.31. Models generated using 2010 reflectance data did not generate models that could predict 2009 data. It is hypothesized that weather events present in 2009 and not in 2010 allowed for a forward calibration transfer, and prevented the reverse calibration transfer. Heuristic selection was superior to minimum RMSEP for transfer, indicating some overfitting in the minimum RMSEP models. The results are demonstrative of a reflectance-composition relationship in the VIS-NIR region for °Brix, pH, and TA requiring additional study and development of further calibrations.

The effects of crop load and berry exposure on the composition of Marlborough Sauvignon blanc grapes and wine from the Brancott vineyard, Blenheim, were explored. Commercially grown, 2-cane and 4-cane Sauvignon blanc vines were used with a row orientation of north-south. Two exposure treatments were imposed in the following manner: complete leaf removal was undertaken in the fruit zone and 50% shade cloth was erected to give a uniform shading treatment to half the trial vines. Weekly thirty-berry and whole bunch samples were taken from each of the 32 plots with the exception of the veraison period when two samples per week were taken. Vine vigour was assessed using pruning and leaf area per vine data. Harvest occurred on different dates for 2-cane and 4-cane pruned vines so that fruit attained from both treatments had similar °Brix. Fruit was processed at the Lincoln University winery. Must analysis and wine analysis were undertaken. As expected, 4-cane vines had almost double the yield of 2-cane vines. Higher crop load significantly reduced leaf area per shoot and shoot thickness. Lower leaf area to fruit ratio for 4-cane berries resulted in delayed onset of veraison and slowed the rate of sugar accumulation. Crop load, which limited leaf area to fruit ratio, appeared to be the dominant factor in determining timing of grape physiological ripeness as expressed by °Brix over other factors such as fruit exposure. Malic acid, tartaric acid, IPMP (iso-propylmethoxypyrazine) and IBMP (iso-butyl-methoxypyrazine) were lower at equivalent °Brix in 4-cane compared with 2-cane berries. Significantly higher concentrations of quercetin were found in exposed compared to shaded berries. Must analysis showed a significant influence of crop load on berry titratable acidity and pH, reflecting berry ripening results. Exposure significantly increased the concentrations of nitrogenous compounds in 4-cane must yet showed no influence on 2-cane must. After wine processing lower malic acid concentrations in wines made from 100% exposed fruit became evident in lower wine titratable acidity but showed no influence on wine pH. Bentonite addition to wines had a small but statistically significant influence on wine by reducing pH, titratable acidity and alcohol. Bound sulphur concentrations were significantly higher in 4-cane versus 2-cane wines. At harvest, methoxypyrazine levels in grapes and wines were very low; IBMP concentrations where significantly lower than those normally found in Sauvignon blanc wines from Marlborough. This was attributed to the absence of basal leaves from the shoots of ripening berries. The results suggest that leaf area to fruit ratio is a powerful determinant of grape and wine quality.

[ES] La industria vitivinícola contemporánea enfrenta varios desafíos clave: optimizar la producción, minimizar la huella ambiental, reducir costos y mejorar la calidad del vino. La integración de la tecnología y herramientas de teledetección ha demostrado ser una solución eficiente para estos problemas. La agricultura de precisión, que incluye el manejo del riego, evaluación y control del follaje, y la identificación de los mejores emplazamientos para cada variedad de uva, es especialmente beneficiosa para esta industria. Un aspecto crucial en la producción de vino es el seguimiento de la madurez de las bayas de uva, mediante la determinación del contenido de azúcar y acidez, lo cual permite establecer la fecha óptima de vendimia. Tras la producción del vino, se evalúan su color y contenido de polifenoles, indicadores de calidad. Las imágenes satelitales son fundamentales en la teledetección para la agricultura de precisión, permitiendo monitorear la salud de los viñedos y controlar las condiciones meteorológicas. Este estudio utilizó imágenes satelitales para relacionar parámetros de calidad del vino (pre y poscosecha) con índices y bandas espectrales derivadas de las imágenes Sentinel-2 obtenidas antes de la cosecha. La investigación abarcó las temporadas de vendimia de 2017 y 2018, estudiando 135.8 hectáreas de viñedos de uvas Cabernet Sauvignon en la comuna de Marchigüe, Valle de Colchagua, Chile Central. El objetivo principal fue desarrollar modelos utilizando índices y variables espectrales de imágenes Sentinel-2 para aproximar parámetros de calidad de uva y vino, como °Brix y pH, así como índice de color, antocianinas totales y fenoles totales del vino. Se espera que estos modelos, aplicados en toda la superficie de trabajo, permitan una gestión diferenciada del cultivo, mejorando la calidad del vino al predecir indicadores pre y poscosecha que influyen en las características sensoriales y la diferenciación de marcas. En las variables precosecha, las bandas de onda corta y el índice de vegetación son más frecuentes, mientras que en las variables poscosecha destacan las bandas de borde rojo, infrarrojo cercano y el índice de humedad. Estos resultados sugieren la necesidad de realizar más estudios o explorar otras especies. Las imágenes satelitales se valoran como herramientas valiosas para mejorar el proceso artesanal y obtener vinos de mejor calidad, destacando la metodología de trabajo adaptable a diversas condiciones ambientales. Uno de los hallazgos más interesantes es la determinación del periodo fisiológico óptimo para el análisis predictivo, específicamente la quincena previa a la vendimia, permitiendo una planificación precisa y oportuna del proceso de cosecha y proporcionando datos esenciales para los enólogos. En cuanto a los coeficientes de determinación obtenidos para °Brix, índice de color y antocianinas totales en la primera temporada, los resultados son altamente positivos, con valores entre 65% y 77%, lo que sugiere una predicción fiable y contribuye a la definición de la cosecha selectiva. Otras variables muestran relaciones menos concluyentes, con coeficientes de determinación entre 42% y 57% en las campañas 2017 y 2018, indicando la necesidad de mejorar el estudio mediante un mayor número de muestras o refinando el proceso de muestreo. Los resultados positivos y la disponibilidad de imágenes satelitales ofrecen la oportunidad de identificar áreas para estudios detallados y cosechas diferenciadas. La selección precisa de uvas con características similares es crucial para mejorar la calidad y productividad del vino. Este estudio resalta la viabilidad de la teledetección y la vendimia selectiva como herramientas clave para gestionar la calidad y estilo del vino, proporcionando nuevas perspectivas en la viticultura. / [CA] La indústria vitivinícola contemporània enfronta diversos reptes clau: optimitzar la producció, minimitzar la petjada ambiental, reduir costos i millorar la qualitat del vi. La integració de la tecnologia i les eines de teledetecció ha demostrat ser una solució eficient per a aquests problemes. L'agricultura de precisió, que inclou el maneig del reg, avaluació i control del fullatge, i la identificació dels millors emplaçaments per a cada varietat de raïm, és especialment beneficiosa per a aquesta indústria. Un aspecte crucial en la producció de vi és el seguiment de la maduresa de les baies de raïm, mitjançant la determinació del contingut de sucre i acidesa, cosa que permet establir la data òptima de verema. Després de la producció del vi, se n'avaluen el color i el contingut de polifenols, indicadors de qualitat. Les imatges satel·litàries són fonamentals en la teledetecció per a l'agricultura de precisió, permetent monitoritzar la salut de les vinyes i controlar les condicions meteorològiques. Aquest estudi va utilitzar imatges satelitals per relacionar paràmetres de qualitat del vi (pre i postcollita) amb índexs i bandes espectrals derivades de les imatges Sentinel-2 obtingudes abans de la collita. La investigació va abastar les temporades de verema de 2017 i 2018, estudiant 135.8 hectàrees de vinyes de raïm Cabernet Sauvignon a la comuna de Marchigüe, Vall de Colchagua, Xile Central. L'objectiu principal va ser desenvolupar models utilitzant índexs i variables espectrals d'imatges Sentinel-2 per aproximar paràmetres de qualitat de raïm i vi, com °Brix i pH, així com índex de color, antocianines totals i fenols totals del vi. S'espera que aquests models, aplicats a tota la superfície de treball, permetin una gestió diferenciada del cultiu, millorant la qualitat del vi en predir indicadors pre i postcollita que influeixen en les característiques sensorials i la diferenciació de marques. A les variables precollita, les bandes d'ona curta i l'índex de vegetació són més freqüents, mentre que a les variables postcollita destaquen les bandes de vora vermella, infraroig proper i l'índex d'humitat. Aquests resultats suggereixen la necessitat de fer més estudis o explorar altres espècies. Les imatges satel·litàries es valoren com a eines valuoses per millorar el procés artesanal i obtenir vins de millor qualitat, destacant la metodologia de treball adaptable a diverses condicions ambientals. Una de les troballes més interessants és la determinació del període fisiològic òptim per a l'anàlisi predictiva, específicament la quinzena prèvia a la verema, permetent una planificació precisa i oportuna del procés de collita i proporcionant dades essencials per als enòlegs. Pel que fa als coeficients de determinació obtinguts per a °Brix, índex de color i antocianines totals a la primera temporada, els resultats són altament positius, amb valors entre 65% i 77%, cosa que suggereix una predicció fiable i contribueix a la definició de la collita selectiva. Altres variables mostren relacions menys concloents, amb coeficients de determinació entre 42% i 57% a les campanyes 2017 i 2018, indicant la necessitat de millorar l'estudi mitjançant un nombre més gran de mostres o refinant el procés de mostreig. Els resultats positius i la disponibilitat d'imatges satel·litals ofereixen l'oportunitat d'identificar àrees per a estudis detallats i collites diferenciades. La selecció precisa de raïms amb característiques similars és crucial per millorar la qualitat i la productivitat del vi. Aquest estudi ressalta la viabilitat de la teledetecció i la verema selectiva com a eines clau per gestionar la qualitat i estil del vi, proporcionant noves perspectives a la viticultura. / [EN] The contemporary wine industry faces several key challenges: optimizing production, minimizing the environmental footprint, reducing costs and improving wine quality. The integration of remote sensing technology and tools has proven to be an efficient solution to these problems. Precision agriculture, which includes irrigation management, canopy assessment and control, and the identification of the best sites for each grape variety, is especially beneficial for this industry. A crucial aspect of wine production is the monitoring of grape berry maturity by determining the sugar and acidity content, which allows the optimal harvest date to be established. After the wine is produced, its color and polyphenol content, quality indicators, are evaluated. Satellite imagery is fundamental in remote sensing for precision agriculture, allowing the health of vineyards to be monitored and weather conditions to be controlled. This study used satellite imagery to relate wine quality parameters (pre- and post-harvest) to indices and spectral bands derived from Sentinel-2 images obtained prior to harvest. The research covered the 2017 and 2018 harvest seasons, studying 135.8 hectares of Cabernet Sauvignon grape vineyards in the commune of Marchigüe, Colchagua Valley, Central Chile. The main objective was to develop models using indices and spectral variables from Sentinel-2 images to approximate grape and wine quality parameters, such as °Brix and pH, as well as color index, total anthocyanins and total phenols of the wine. It is expected that these models, applied across the entire work area, will allow for differentiated crop management, improving wine quality by predicting pre- and postharvest indicators that influence sensory characteristics and brand differentiation. In the pre-harvest variables, shortwave bands and vegetation index are more frequent, while in the post-harvest variables, red-edge bands, near infrared and moisture index stand out. These results suggest the need to conduct further studies or explore other species. Satellite images are valued as valuable tools to improve the artisanal process and obtain better quality wines, highlighting the work methodology adaptable to diverse environmental conditions. One of the most interesting findings is the determination of the optimal physiological period for predictive analysis, specifically the fortnight prior to harvest, allowing precise and timely planning of the harvest process and providing essential data for winemakers. Regarding the coefficients of determination obtained for °Brix, color index and total anthocyanins in the first season, the results are highly positive, with values between 65% and 77%, suggesting a reliable prediction and contributing to the definition of selective harvesting. Other variables show less conclusive relationships, with coefficients of determination between 42% and 57% in the 2017 and 2018 seasons, indicating the need to improve the study by increasing the number of samples or refining the sampling process. The positive results and the availability of satellite images offer the opportunity to identify areas for detailed studies and differentiated vintages. Accurate selection of grapes with similar characteristics is crucial to improve wine quality and productivity. This study highlights the feasibility of remote sensing and selective harvesting as key tools for managing wine quality and style, providing new perspectives in viticulture. / Fredes Castro, SN. (2024). Modelación de parámetros de calidad de uva vinífera con índices satelitales provenientes de imágenes de resolución espacial media para el manejo diferenciado de viñedos en Chile [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/211473

Plastids are the cellular organelles where many of the visual, health and flavor-related metabolites are produced and stored in the fruit, and therefore are valuable components for consumers and breeders. The more sugar and flavor the fruit has, the more appreciated is for the consumer and industry. Thus, one of the breeder's goals is to obtain new varieties with fruits improved in these aspects. Paradoxically, fruits with a high content in chloroplasts have been avoided by the breeders because it usually suffers of oxidative stress disorders; such yellow shoulder impairment and fruit cracking when the light intensity increases. For this reason breeding efforts has been focused mainly on avoiding fruit losses and organoleptic characteristics have been neglected. This thesis aims to improve tomato fruit quality by engineering plants to produce fruits with enhanced fruit chloroplast functions and improved tolerance to oxidative stress, using cisgenic/ intragenic approaches. SlGLK1, SlGLK2 and SlAPRR2 transcription factors have been suggested to be involved in chloroplast development. Tomato MoneyMaker plants were engineered to express SlGLKs and SlAPRR2 either singly or in combination early in development. Those lines provide fruits which accumulate more sugars, carotenoids and specific volatiles than WT. The fruit chloroplast enhanced lines were characterized at the structural, metabolic, proteomics and transcriptomics. A novel additive effect in the chloroplast regulation network resulted when both transcription factors were coexpressed and a hypothesis for this effect is presented. In addition, two tomato traditional varieties (Muchamiel and Pera) expressing tomato genes for BMW anthocyanin regulatory complex under the control of the light inducible promoter (PLI) were produced and characterized. Engineered tomato plants showed large accumulation of anthocyanin specifically in the fruit peel and in Type VI trichomes. Characterization of those tissues indicated specific alterations of the flavonoid pathway that were highly dependent on the light conditions. These tomato lines could be of high interest to protect the fruit chloroplast enhancement lines from eventual stresses involving ROS, and also to assess the effect on plant growth under high light stress and in plant-pest interaction studies. / Los plastidos son orgánulos celulares donde se producen y almacenan muchos de los metabolitos relacionados con atributos organolépticos y compuestos beneficiosos para la salud, por lo tanto se consideran componentes de alto valor añadido para consumidores y mejoradores vegetales. Cuanto mayor contenido en azúcares solubles y sabor presente el fruto más se valoran por los consumidores y la industria. Por lo tanto uno de los objetivos actuales de los mejoradores de tomate es mejorar el fruto en estos aspectos. Paradójicamente, se ha seleccionado en contra de frutos con alto contenido en cloroplastos porque este carácter, bajo alta intensidad lumínica, suele estar asociado a daños en el fruto por estrés oxidativo; como los hombros amarillos del tomate o el agrietado del fruto. Por este motivo los esfuerzos en mejora se han orientado principalmente a evitar pérdidas y consecuentemente la calidad organoléptica se ha visto reducida. El objetivo de esta tesis es mejorar la calidad del fruto de tomate mediante el empleo de técnicas de ingeniería genética orientadas a incrementar los cloroplastos en fruto y mejorar la tolerancia al estrés oxidativo con una aproximación cis/ intragenica. Los factores de transcripción SlGLK1, SlGLK2 y SlAPRR2 han sido estudiados por influir en el desarrollo del cloroplasto. Plantas de tomate de variedad MoneyMaker fueron mejoradas genéticamente para expresar de forma individual o conjunta SlGLKs y SlAPRR2 en estadios tempranos de desarrollo. Estas líneas proveen frutos con mayor acumulo de azúcares, carotenos y volátiles que el control MoneyMaker. Las líneas potenciadas en desarrollo de cloroplastos se caracterizaron a nivel estructural, metabólico, proteómico y transcriptómico. Se descubrió un novedoso efecto aditivo en la regulación génica del cloroplasto cuando ambos factores de transcripción se expresan simultáneamente y se presentó una hipótesis para dicho efecto. Además se caracterizaron dos variedades tradicionales de tomate (Muchamiel and Pera) diseñadas para expresar genes pertenecientes al complejo de regulación de antocianinas BMW, bajo el control del promotor inducible por luz (PLI). Las plantas mejoradas genéticamente presentan una gran acumulación de antocianos, especialmente en piel de fruto y en tricomas tipo VI. Caracterización de estos tejidos indican alteraciones específicas en la ruta de flavonoides y una alta dependencia a condiciones de luz. Estas plantas podrían ser de gran interés para proteger frutos con altos niveles de cloroplastos frente al estrés oxidativo generado por ROS, para evaluar el efecto en el crecimiento de la planta bajo condiciones de alta luz y en futuros estudios de interacción planta-patógenos / Els plastidis són orgànuls cel.lulars on es produeixen i emmagatzemen molts dels metabòlits relacionats amb atributs organolèptics i composts beneficiosos per a la salut, per tant es consideren components d'alt valor afegit per a consumidors i milloradors vegetals. Quant major contingut en sucres solubles i sabor presenta el fruït, més serà valorat per part dels consumidors i la industria. Paradoxalment, s'ha seleccionat en contra dels fruïts amb alt contingut en cloroplasts perquè aquest caràcter, davall alta intensitat lumínica, sol estar associat amb danys en el fruït per estrés oxidatiu; com muscles groguencs de la tomata o clevitjament del fruït. Per aquest motiu, l'esforç en millora s'ha orientat principalment a evitar pèrdues de manera que la qualitat organolèptica s'ha vist reduïda. L'objectiu d'aquesta tesi es millorar la qualitat del fruït de tomata mitjançant l'ús de tècniques d'enginyeria genètica orientades a incrementar els cloroplasts al fruït i millorar la tolerància a l'estrès oxidatiu amb una aproximació cis/intragènica. Plantes de tomata de la varietat MoneyMaker foren millorades genèticament per expressar de manera individual o conjunta SlGLK1, SlGLK2 y SlAPRR2 als moments inicials del desenvolupament. Aquestes línies donen fruïts amb major acumulació de sucres, carotens i volàtils que el control MoneyMaker. Les línies potenciades amb el desenvolupament de cloroplasts es caracteritzaren a nivell estructural, metabòlic, proteòmic i transcriptòmic. Es va descobrir un nou efecte additiu en la regulació gènica del cloroplast quan ambdós factors de transcripció s'expressen de manera simultània i es va presentar una hipòtesi per a dit efecte. A més, es van caracteritzar dos varietats tradicionals de tomata (Muchamiel i Pera) dissenyades per a expressar gens que pertanyen al complex de regulació d'antocians BMW, davall el control del promotor induïble per llum (PLI). Les plantes millorades genèticament presentaren una gran acumulació d'antocians, especialment a la pell del fruït i en tricomes de tipus VI. La caracterització d'aquest teixit indica alteracions específiques en la ruta dels flavonoides i una altra dependència a condicions de llum. Aquestes plantes podrien ser de gran interès per a protegir els fruïts d'alts nivells de cloroplasts front a l'estrès oxidatiu generat pels ROS, i per a avaluar l'efecte en el creixement de la planta davall condicions d'alta llum i en futurs estudis d'interacció planta-patògen. / Cocaliadis Caisson, MF. (2017). A multilevel, developmentally controlled gene engineering strategy for tomato fortification and protection [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90401