Resumo: O presente trabalho teve por objetivo avaliar cinco seleções da laranjeira 'Valência', quanto ao potencial industrial com relação às variedades Natal e Valência, enxertadas sobre citrumeleiro 'Swingle' (experimento I) e a tangerineira 'Sunki' (experimento II), avaliando-se o desenvolvimento vegetativo das plantas, porcentagem de pegamento dos frutos, produção e características físico - químicas dos frutos (sólidos solúveis totais - °Brix, acidez, "ratio", porcentagem de suco, índice tecnológico, tamanho dos frutos). Os experimentos foram conduzidos na Estação Experimental de Citricultura de Bebedouro (E.E.C.B.), município de Bebedouro-SP. Os plantios dos experimentos foram realizados em fevereiro de 2001, sob espaçamentos de 7,0 m entre linhas e 5,0 m entre plantas (285 plantas/ha) e 7,0 m entre linhas e 3,0m entre plantas (476 plantas/ha), respectivamente para os experimentos I e II. O delineamento experimental, para ambos experimentos, foi em blocos ao acaso, duas plantas por parcela, quatro repetições e 7 tratamentos, constituídos pelas seguintes variedades copas: 1) Natal, 2) Valência, 3) Valência Don João, 4) Valência Late Burjasot IVIA 35-2, 5) Valência Rohde Red SRA-36, 6) Valência Temprana IVIA-25, 7) Valência Campbell. Para desenvolvimento vegetativo das plantas e características físicas referentes a massa, diâmetro e altura de frutos as seleções 'Valência Late Burjasot' IVIA 35-2 e 'Don João' apresentaram as maiores médias. As mesmas seleções citadas anteriormente apresentaram as melhores médias para porcentagem de pegamento para o experimento I, no experimento II as seleções estudadas não diferiram. Quanto à produção, a seleção 'Valência Late Burjasot' IVIA 35-2 destacou-se na segunda safra. / Abstract: The aim of the current work was to compare the conduct of five 'Valência' sweet oranges selection with in it's industrial potential in relation to the varieties Natal and Valencia on two rootstocks: 'Swingle' (experiment I) and 'Sunki' (experiment II), evaluating the vegetative growth, percentage of fruit set, yield and physical and chemical fruit characteristics. Two experiments were set up in February 2001, at Bebedouro city, São Paulo State, Brazil. The experiments I and II were carried out with the spacements of 7.0 m between rows with 5.0 m between trees and 7.0 m between rows with 3.0 m between trees, respectively. The experimental design used was a randomized blocks, with four replications and two trees per each seven plots. The crown varieties tested were 1) 'Natal', 2) 'Valência', 3) 'Valência Don João', 4) 'Valência Late Burjasot' IVIA 35-2, 5) 'Valência Rohde Red' SRA-36, 6) 'Valência Temprana' IVIA-25, 7) 'Valência Campbell'. For vegetative growth and the physical characteristics referring to mass diameter and height of fruits, the selections 'Valência Late Burjasot' IVIA 35-2 e 'Don João' presented the highest averages The same selections also presented the best averages for percentage of fruit set in experiment I, while in experiment II the selections did not differ. In relationship to production, the selection ' Valência Late Burjasot' IVIA 35-2 stood out in the second crop. Already for revenue in juice and technological index the selections 'Valência Late Burjasot' IVIA 35-2 , 'Don João' and 'Valência Campbell' presented the largest averages comparing the varieties Valência and Natal. / Orientador: Antonio Baldo Geraldo Martins / Coorientador: Eduardo Sanches Stuchi / Banca: José Antonio Alberto da Silva / Banca: Luiz de Souza Corrêa / Mestre

Um dos aspectos que devem ser considerados no mercado de frutas frescas de pessegueiro é a qualidade de seus frutos. Considera-se a aparência como fator importante, sendo a coloração da epiderme relevante, pois se associa com a maturação e o sabor dos frutos. Uma das técnicas de manejo que visam melhorar a qualidade dos frutos é a poda verde, que tem como intuito principal de aumentar a penetração da luz no interior da copa e consequentemente favorecer a pigmentação, bem como, melhorar o sabor dos frutos. Porém, esta técnica pode apresentar resultados variáveis, de acordo com a época e a forma em que a mesma é realizada. O objetivo deste trabalho foi de determinar o período e a forma de execução da poda verde para melhorar a qualidade dos frutos de pessegueiros. O trabalho foi conduzido em pomar comercial no município de Dois Vizinhos (PR), nos ciclos produtivos 2009/2010,2010/2011 e 2011/2012. Foi utilizados pêssegos dos cultivares Charme e Maciel. Foi utilizado delineamento experimental inteiramente casualizados, em esquema fatorial 3 x 3 (época da poda verde x técnica de manejo da poda verde), com 4 repetições, constituindo-se cada parcela de 2 plantas. As épocas de realização da poda verde foram na terceira, quarta e quinta semanas antes da colheita. As técnicas de manejo foram primeiro, baseadas na retirada dos ramos ladrões no interior e na base dos ramos, ramos quebrados e mal posicionados e, segundo no dobramento destes, permanecendo-os ligados a planta. A campo foi avaliado a capacidade produtiva das plantas e análises fisiológicas nos ciclos 2010/2011 e 2011/2012, e em laboratório foram analisadas as características físico-química e bioquímica dos frutos. Conclui se ao final deste trabalho que o uso da poda verde em plantas de pessegueiro Charme e Maciel a cinco e quatro semanas antes da colheita, com a técnica de corte e de dobramento dos ramos proporcionou melhorias na qualidade de seus frutos. / One of the aspects that it should be considered in the fresh fruit market peach is the fruit quality. The visual aspect is the most important factor, it being the skin color relevant because it is associated with the fruit maturation and flavor. One of cultural techniques to improve the fruit quality is summer pruning, which has as main purpose to increase light penetration within the canopy tree and consequently it to promote the pigmentation, as well as improvements in the fruit flavor. However, this technique can to present results variable according to the time and manner in which it was realized. The aim of this work was evaluate the time and management type for summer pruning to obtain peach quality. The work was carried out at commercial orchard from Dois Vizinhos city, Paraná State, Brazil, in 2009/2010, 2010/2011 and 2011/2012 cycle. It was used Charme and Maciel peach varieties. The experimental design was completely randomized, in factorial 3. x 3 (summer pruning time x summer pruning management type), with 4 replications of two plants by plot. The summer pruning time were in the third, fourth and fifth week before harvest. First the cultural practices were realized removal vigorous vertical shoot inside and in the base of crown, break shoots and bad shoots position in the tree. The second in the bending shoots in the tree. The yield and physiology characteristics tree on orchard in 2010/2011 and 2011/2012 cycle and fruit physical-chemical- biochemistry variables were evaluated on Plant Physiology Laboratory. It was concluded that the summer pruning use in Charme and Maciel peach tree during four and five weeks before harvest, with the pruning and beding shoot increased the fruit quality.

Um dos aspectos que devem ser considerados no mercado de frutas frescas de pessegueiro é a qualidade de seus frutos. Considera-se a aparência como fator importante, sendo a coloração da epiderme relevante, pois se associa com a maturação e o sabor dos frutos. Uma das técnicas de manejo que visam melhorar a qualidade dos frutos é a poda verde, que tem como intuito principal de aumentar a penetração da luz no interior da copa e consequentemente favorecer a pigmentação, bem como, melhorar o sabor dos frutos. Porém, esta técnica pode apresentar resultados variáveis, de acordo com a época e a forma em que a mesma é realizada. O objetivo deste trabalho foi de determinar o período e a forma de execução da poda verde para melhorar a qualidade dos frutos de pessegueiros. O trabalho foi conduzido em pomar comercial no município de Dois Vizinhos (PR), nos ciclos produtivos 2009/2010,2010/2011 e 2011/2012. Foi utilizados pêssegos dos cultivares Charme e Maciel. Foi utilizado delineamento experimental inteiramente casualizados, em esquema fatorial 3 x 3 (época da poda verde x técnica de manejo da poda verde), com 4 repetições, constituindo-se cada parcela de 2 plantas. As épocas de realização da poda verde foram na terceira, quarta e quinta semanas antes da colheita. As técnicas de manejo foram primeiro, baseadas na retirada dos ramos ladrões no interior e na base dos ramos, ramos quebrados e mal posicionados e, segundo no dobramento destes, permanecendo-os ligados a planta. A campo foi avaliado a capacidade produtiva das plantas e análises fisiológicas nos ciclos 2010/2011 e 2011/2012, e em laboratório foram analisadas as características físico-química e bioquímica dos frutos. Conclui se ao final deste trabalho que o uso da poda verde em plantas de pessegueiro Charme e Maciel a cinco e quatro semanas antes da colheita, com a técnica de corte e de dobramento dos ramos proporcionou melhorias na qualidade de seus frutos. / One of the aspects that it should be considered in the fresh fruit market peach is the fruit quality. The visual aspect is the most important factor, it being the skin color relevant because it is associated with the fruit maturation and flavor. One of cultural techniques to improve the fruit quality is summer pruning, which has as main purpose to increase light penetration within the canopy tree and consequently it to promote the pigmentation, as well as improvements in the fruit flavor. However, this technique can to present results variable according to the time and manner in which it was realized. The aim of this work was evaluate the time and management type for summer pruning to obtain peach quality. The work was carried out at commercial orchard from Dois Vizinhos city, Paraná State, Brazil, in 2009/2010, 2010/2011 and 2011/2012 cycle. It was used Charme and Maciel peach varieties. The experimental design was completely randomized, in factorial 3. x 3 (summer pruning time x summer pruning management type), with 4 replications of two plants by plot. The summer pruning time were in the third, fourth and fifth week before harvest. First the cultural practices were realized removal vigorous vertical shoot inside and in the base of crown, break shoots and bad shoots position in the tree. The second in the bending shoots in the tree. The yield and physiology characteristics tree on orchard in 2010/2011 and 2011/2012 cycle and fruit physical-chemical- biochemistry variables were evaluated on Plant Physiology Laboratory. It was concluded that the summer pruning use in Charme and Maciel peach tree during four and five weeks before harvest, with the pruning and beding shoot increased the fruit quality.

The effect of source-sink relationships on the performance of tomato and hot pepper was investigated in glasshouse experiments by pruning tomato trusses and hot pepper fruit from plants trained to a single stem. The objectives were to characterize the effect of time, method and intensity of pruning on the yield and quality of tomato and hot pepper. Pruning at anthesis as compared to pruning at fruit-set had little effect on yield and fruit quality of both crops. Yield per truss increased steadily with intensity of pruning in tomato, due to increase in fruit size and fruit number per truss. Thus, total yield was not affected by pruning. In hot pepper fruit size increased with intensity of pruning but total yield was significantly reduced and total plant dry mass depressed at higher source : sink ratios (two and three fruit pruned out of a total of six). Occurrence of fruit disorders such as blossom-end rot and fruit cracking increased with increasing source: sink ratio. Pruning of one truss in tomato and one fruit in hot pepper gave the best fruit quality in terms of fruit size, pericarp thickness and freedom from defects, without decreasing total and marketable yield. Removing a middle truss of tomato (third truss) gave the highest yield as compared to removing the youngest truss (sixth truss) or the oldest truss (first truss). The yield increase (relative to the control) in the remaining individual trusses tended to decrease with increasing distance of the trusses from the pruned truss. In hot pepper removal of the youngest fruit (sixth fruit) resulted in the highest yield in comparison to removal of the middle fruit (third fruit) and the oldest fruit (first fruit). The quantity of yield increase in the remaining individual fruits had no consistent trend regarding the relative distance of the fruits from the pruned fruit. Two pruning methods were tried on hot pepper and tomato to compare yield and fruit quality. The first method involved pruning of the first three consecutive trusses of tomato and the first three consecutive fruit of hot pepper out of a total of six. The second method involved pruning of three alternating tomato trusses or hot pepper fruit. Yield and yield components did not differ significantly for the two methods, but pruning alternate trusses of tomato and fruit of hot pepper reduced occurrence of fruit disorders. / Dissertation (MSc (Agric) Agronomy)--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

Philosophiae Doctor - PhD / Apple fruit quality is of utmost importance to apple farmers and breeders in the selection and commercialization of new cultivars. Fruit size, colour, texture, firmness and taste are all traits that affect the quality of fruit. In this study the genetic contribution of these traits, and others were evaluated in order to generate the genetic markers required for the application of marker assisted selection in fruit quality breeding. Three mapping populations, ‘Prima’ x ‘Anna’, ‘Golden Delicious’ x ‘Priscilla’ and ‘Golden Delicious’ x ‘Anna’, consisting of 87, 87 and 141 respectively, were used in the study. Fruit samples were analysed, using a range of visual, physical and sensory measurements, over a period of three years, and the data was then correlated using statistical analysis. Traits analysed included stripe-ness, fruit colour, fruit size, fruit form, ground colour, russet, texture, fruit firmness, juiciness, sugar content, acidity, taste, skin toughness, %TSS, fruit mass and diameter. ANOVA detected significant levels of variation between the three families for all traits except taste and russet; while highly significant ‘within family’ variation was also observed for all traits in pre- and post-storage analyses, except for sugar content (sweetness) and fruit form. Within family variation also contributed the largest percentage towards the variance components of all traits. Heritability estimates found stripe-ness to be the most heritable trait, from subjective analyses, while heritability values ranged from 0.41 to 0.84 for instrumentally measured traits. The genetic maps for the three populations were generated using both published microsatellites and new EST-SSR and DART markers, using JoinMap 4.0". The integrated genetic linkage maps of ‘Prima’ x ‘Anna’, ‘Golden Delicious’ x ‘Priscilla’, ‘Golden Delicious’ x ‘Anna’ consisted of 398 (133 SSR and 265 DArT), 353 (80 SSR and 273 DArT) and 213 (87 SSR and 126 DArT) markers respectively. The maps were 1021.6cM, 1079cM and 1302.7cM in length, respectively. Location of quantitative trait loci (QTL) for 14 fruit quality traits was detected using MapQTL 5.0" and a total of 79 pre-storage and 60 poststorage QTLs were identified on the three mapping populations. Comparative genome analysis and the role of various genes on the outcome of fruit quality can now be investigated. Using the integrated genetic maps, and the QTLs identified, candidate markers associated with these QTL can be used for marker-assisted selection, to increase the speed and efficiency of the apple breeding program.

One of the factors that maintains fruit quality is its microbial flora. Fruit holds a natural non-pathogenic epiphytic microflora but can become contaminated with pathogenic microorganisms during export, causing either postharvest decay or possibly resulting in a food safety risk. In order to study microbial dynamics on fruit surfaces and the environment fruit moves through in the export chain, fruit washings were made, surfaces were sampled and total populations and diversities determined per cm2. Hygiene and safety levels for fruit export environments were hereby determined by sampling various points along the apple export chain, which included two farms and a harbour in South Africa and two harbours, two repacking facilities and two retail centres in Europe. In this first study of its kind, all the surfaces that were sampled exceeded the international standard for cleaning efficacy of food-processing equipment that is <5 cfu/cm2, while several areas exceeded the maximum acceptable index level of microbial air contamination of 22 cfu/h in food industries. Washing of containers on a harbour in South Africa did not have a significant impact on microbial populations. Regarding fruit quality, it was determined that apple microflora fluctuate throughout the export process and that postharvest pathogens that are known to cause great economic losses in the apple industry, proved to be of little significance in this investigation. The presence of six foodborne pathogens i.e. Shigella sonnei, Salmonella muenchen, Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Staphylococcus epidermidi/s was monitored throughout the chain. Of these, only S. aureus and E. coli were recorded, although pathogenicity was not confirmed for the latter. Staphylococcus aureus was found in containers and at a retail centre in Europe, and S. aureus and S. epidermidis were recorded on apple surfaces for the first time. Escherichia coli was present in great numbers in fruit washing water on a farm in South Africa. Since the standard for food premises is very stringent and perhaps inapplicable for fresh fruit handling and holding facilities, future research should include development of a more realistic hygiene standard for fresh fruit environments. / Dissertation (MSc(Agric) : Plant Pathology)--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted

[ES] El objetivo de esta tesis doctoral es evaluar la técnica de imagen hiperespectral en el rango visible e infrarrojo cercano, en combinación con técnicas quimiométricas para la evaluación de la calidad de la fruta en poscosecha de manera eficaz y sostenible. Con este fin, se presentan diferentes estudios en los que se evalúa la calidad de algunas frutas que por su valor económico, estratégico o social, son de especial importancia en la Comunidad Valenciana como son el caqui 'Rojo Brillante', la granada 'Mollar de Elche', el níspero 'Algerie' o diferentes cultivares de nectarina. En primer lugar se llevó a cabo la monitorización de la calidad poscosecha de nectarinas 'Big Top' y 'Magique' usando imagen hiperespectral en reflectancia y transmitancia. Al mismo tiempo se evaluó la transmitancia para la detección de huesos abiertos. Se llevó a cabo también un estudio para distinguir los cultivares 'Big Top' y "Diamond Ray", los cuales poseen un aspecto muy similar pero sabor diferente. En cuanto al caqui 'Rojo Brillante', la imagen hiperespectral fue estudiada por una parte para monitorear su madurez, y por otra parte para evaluar la astringencia de esta fruta, que debe ser completamente eliminada antes de su comercialización. Las propiedades físico-químicas de la granada 'Mollar de Elche' fueron evaluadas usando imagen de color e hiperespectral durante su madurez usando la información de la fruta intacta y de los arilos. Finalmente, esta técnica se usó para caracterizar e identificar los defectos internos y externos del níspero 'Algerie'. En la predicción de los índices de calidad IQI y RPI usando imagen en reflectancia y transmitancia se obtuvieron valores de R2 alrededor de 0,90 y en la discriminación por firmeza, una precisión entorno al 95 % usando longitudes de onda seleccionadas. En cuanto a la detección de huesos abiertos, el uso de la imagen hiperespectral en transmitancia obtuvo un 93,5 % de clasificación correcta de frutas con hueso normal y 100 % con hueso abierto usando modelos PLS-DA y 7 longitudes de onda. Los resultados obtenidos en la clasificación de los cultivares 'Big Top' y 'Diamond Ray' mostraron una fiabilidad superior al 96,0 % mediante el uso de modelos PLS-DA y 14 longitudes de onda seleccionadas, superando a la imagen de color (56,9 %) y a un panel entrenado (54,5 %). Con respecto al caqui, los resultados obtenidos indicaron que es posible distinguir entre tres estados de madurez con una precisión del 96,0 % usando modelos QDA y se predijo su firmeza obteniendo un valor de R2 de 0,80 usando PLS-R. En cuanto a la astringencia, se llevaron a cabo dos estudios similares en los que en el primero se discriminó la fruta de acuerdo al tiempo de tratamiento con altas concentraciones de CO2 con una precisión entorno al 95,0 % usando QDA. En el segundo se discriminó la fruta de acuerdo a un valor de contenido en taninos (0,04 %) y se determinó qué área de la fruta era mejor para realizar esta discriminación. Así se obtuvo una precisión del 86,9 % usando la zona media y 23 longitudes de onda. Los resultados obtenidos para la granada indicaron que la imagen de color e hiperespectral poseen una precisión similar en la predicción de las propiedades fisicoquímicas usando PLS-R y la información de la fruta intacta. Sin embargo, cuando se usó la información de los arilos, la imagen hiperespectral fue más precisa. En cuanto a la discriminación del estado de madurez usando PLS-DA, la imagen hiperespectral ofreció mayor precisión, 95,0 %, usando la información de la fruta intacta y del 100 % usando la de los arilos. Finalmente, los resultados obtenidos para el níspero indicaron que la imagen hiperespectral junto con el método de clasificación XGBOOST pudo discriminar entre muestras con y sin defectos con una precisión del 97,5 % y entre muestras sin defectos o con defectos internos o externos con una precisión del 96,7 %. Además fue posible distinguir entre los dife / [CA] L'objectiu de la present tesi doctoral se centra en avaluar la capacitat de la imatge hiperespectral en el rang visible i infraroig pròxim, en combinació amb mètodes quimiomètrics, per a l'avaluació de la qualitat de la fruita en post collita de manera eficaç i sostenible. A aquest efecte, es presenten diferents estudis en els quals s'avalua la qualitat d'algunes fruites que pel seu valor econòmic, estratègic o social, són d'especial importància a la Comunitat Valenciana com són el caqui 'Rojo Brillante', la magrana 'Mollar de Elche', el nispro 'Algerie' o diferents cultivares de nectarina. En primer lloc es va dur a terme la monitorització de la qualitat post collita de nectarines 'Big Top' i 'Magique' per mitjà d'imatge hiperespectral en reflectància i trasnmitancia. Així mateix es va avaluar la transmitància per a la detecció d'ossos oberts. Es va dur a terme també un estudi per distingir els cultivares 'Big Top' i 'Diamond Ray', els quals posseeixen un aspecte molt semblant però sabor diferent. Pel que fa al caqui 'Rojo Brillante', la imatge hiperespectral va ser estudiada d'una banda per a monitoritzar la seua maduresa, i per un altre costat per avaluar l'astringència, que ha de ser completament eliminada abans de la seua comercialització. Les propietats fisicoquímiques de la magrana 'Mollar de Elche' van ser avaluades per la imatge de color i hiperespectral durant la seua maduresa usant la informació de la fruita intacta i els arils. Finalment, aquesta tècnica es va fer servir per caracteritzar i identificar els defectes interns i externs del nispro 'Algerie'. En la predicció dels índexs de qualitat IQI i RPI usant imatge en reflectància com en trasnmitancia es van obtindre valors de R2 al voltant de 0,90 i en la discriminació per fermesa una precisió entorn del 95,0 % utilitzant longituds d'ona seleccionades. Pel que fa a la detecció d'ossos oberts, l'ús de la imatge hiperespectral en transmitància va obtindre un 93,5 % classificació correcta de fruites amb os normal i 100 % amb os obert usant models PLS-DA i 7 longituds d'ona. Els resultats obtinguts en la classificació dels cultivares 'Big Top' i 'Diamond Ray' van mostrar una fiabilitat superior al 96,0 % per mitjà de l'ús de models PLS-DA i 14 longituds d'ona, superant a la imatge de color (56,9 %) i a un panell sensorial entrenat (54,5 %). Quant al caqui, els resultats obtinguts van indicar que és possible distingir entre tres estats de maduresa amb una precisió del 96,0 % usant models QDA i es va predir la seua fermesa obtenint un valor de R2 de 0,80 usant PLS-R. Pel que fa a l'astringència, es van dur a terme dos estudis similars en què el primer es va discriminar la fruita d'acord al temps de tractament amb altes concentracions de CO2 amb una precisió al voltant del 95,0 % usant QDA. En el segon, es va discriminar la fruita d'acord a un valor de contingut en tanins (0,04 %) i es va determinar quina part de la fruita era millor per a realitzar aquesta discriminació. Així es va obtindre una precisió del 86,9 % usant la zona mitjana i 23 longituds d'ona. Els resultats obtinguts per la magrana van indicar que la imatge de color i hiperespectral posseïxen una precisió semblant a la predicció de les propietats fisicoquímiques usant PLS-R i la informació de la fruita intacta. No obstant això, quan es va usar la informació dels arils, la imatge hiperespectral va ser més precisa. Quant a la discriminació de l'estat de maduresa usant PLS-DA, la imatge hiperespectral va oferir major precisió (95,0 %) usant la informació de la fruita intacta i del 100 % usant la dels arils. Finalment, els resultats obtinguts pel nispro indiquen que la imatge hiperespectral juntament amb el mètode de classificació XGBOOST va poder discriminar entre mostres amb i sense defectes amb una precisió del 97,5 % i entre mostres sense defectes o amb defectes interns o externs amb una precisió del 96,7 %. A més, va ser possible distingir entre / [EN] The objective of this doctoral thesis is to evaluate the potential of the hyperspectral imaging in the visible and near infrared range in combination with chemometrics for the assessment of the postharvest quality of fruit in a non-destructive, efficient and sustainable manner. To this end, different studies are presented in which the quality of some fruits is evaluated. Due to their economic, strategic or social value, the selected fruits are of special importance in the Valencian Community, such as Persimmon 'Rojo Brillante', the pomegranate 'Mollar de Elche', the loquat 'Algerie' or different nectarine cultivars. First, the quality monitoring of 'Big Top' and 'Magique' nectarines was carried out using reflectance and transmittance images. At the same time, transmittance was evaluated for the detection of split pit. In addition, a classification was performed to distinguish the 'Big Top' and 'Diamond Ray' cultivars, which look very similar but have different flavour. Whereas that for the 'Rojo Brillante' persimmon, the hyperspectral imaging was studied on the one hand to monitor its maturity, and on the other hand to evaluate the astringency of this fruit, which must be completely eliminated before its commercialization. The physicochemical properties of the 'Mollar de Elche' pomegranate were evaluated by means of hyperspectral and colour imaging during its maturity using the information from the intact fruit and arils. Finally, this technique was used to characterise and identify the internal and external defects of the 'Algerie' loquat. In the prediction of the IQI and RPI quality indexes using reflectance and transmittance images, R2 values around 0.90 were obtained and in the discrimination according to firmness, accuracy around 95.0 % using selected wavelengths was obtained. Regarding the split pit detection, the use of the hyperspectral image in transmittance mode obtained a 93.5 % of fruits with normal bone correctly classified and 100% with split pit using PLS-DA models and 7 wavelengths. The results obtained in the classification of 'Big Top' and 'Diamond Ray' fruits show accuracy higher than 96.0 % by using PLS-DA models and 14 selected wavelengths, higher than the obtained with colour image (56.9 %) and a trained panel (54.5 %). According to persimmon, the results obtained indicated that it is possible to distinguish between three states of maturity with an accuracy of 96.0 % using QDA models and its firmness was predicted obtaining a R2 value of 0.80 using PLS-R. Regarding astringency, two similar studies were carried out. In the first study, the fruit was classified according to the time of treatment with high concentrations of CO2 with a precision of around 95.0 % using QDA. In the second, the fruit was discriminated according to a threshold value of soluble tannins (0.04 %) and was determined what fruit area was better to perform this discrimination. Thus, an accuracy of 86.9 % was obtained using the middle area and 23 wavelengths. The results obtained for the pomegranate indicated that the use of colour and hyperspectral images have a similar precision in the prediction of physicochemical properties using PLS-R and the intact fruit information. However, when the information from the arils was used, the hyperspectral image was more accurate. Regarding the discrimination by the state of maturity using PLS-DA, the hyperspectral image offered greater precision, of 95.0 % using the information from the intact fruit and 100 % using that from the arils. Finally, the results obtained for the 'Algerie' loquat indicated that the hyperspectral image with the XGBOOST classification method could discriminate between sound samples and samples with defects with accuracy of 97.5 % and between sound samples or samples with internal or external defects with an accuracy of 96.7 %. It was also possible to distinguish between the different defects with an accuracy of 95.9 %. / Munera Picazo, SM. (2019). Application of hyperspectral imaging combined with chemometrics for the non-destructive evaluation of the quality of fruit in postharvest [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/125954 / TESIS

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Two experiments were conducted to determine the influence of light on 'Norman' and 'Cresthaven' peach fruit quality characteristics. Of primary interest was the relationship between ground color and flesh firmness. Light levels were manipulated by use of shade cloth, reflective mulch, and aluminum foil. 'Norman' trees, with a randomly chosen half of the canopy covered with 73% shade cloth, had fruit with lower levels of red color, soluble solids concentration (SSC), specific leaf weight, and average photosynthetic photon flux (PPF) than did non-shaded trees. Foil-covered 'Cresthaven' fruit were larger, less firm, and had lower SSC than non-covered fruit. Covered fruit developed yellow but not red color. Position of the fruit within the canopy of the tree also affected fruit quality characteristics. Inside fruit on both 'Norman' and 'Cresthaven' trees were smaller and firmer, had lower SSC, and were less red than fruit from the canopy exterior. The position effect was probably due to the degree of light exposure and not to the distance from the roots. Fruit on the inside of the tree canopies received much lower average PPF than outside fruit. Relationships were evaluated between ground color and firmness for both cultivars. At a given hue angle, fruit developing in high-light environments were firmer than fruit from low-light environments for 'Cresthaven', but the opposite was true for 'Norman'. Therefore, canopy position or the light environment in the vicinity of the developing fruit does not consistently influence the relationship between hue angle on the non-blush side of the fruit, and flesh firmness. / Master of Science

Anaerobic soil disinfestation (ASD) is a promising alternative to chemical fumigation to control soil-borne plant pathogens and weeds. This research focused on evaluating several locally available carbon sources for ASD on weed control, evaluating the performance of brewers' spent grain (a promising carbon source) under field conditions, and evaluating whether yeast addition enhanced the effectiveness of ASD treatments. A series of greenhouse trials were conducted at the Southern Piedmont AREC (Agricultural Research and Extension Center). The greenhouse trials were conducted in PVC tubes, 20 cm tall and 15 cm in diameter. The first set of trials evaluated ASD conducted over 21-day periods of ASD using locally available carbon sources. The carbon sources included brewer`s spent grain, buckwheat (Fagopyrum esculentum), cowpea (Vigna unguiculata), paper mulch, peanut (Arachis hypogaea) shells, rice bran, sorghum-sudangrass (Sorghum drummondii), and waste coffee grounds applied at 4 mg of C/g of soil. The targeted weed species included common chickweed (Stellaria media (L.) Vill.), redroot pigweed (Amaranthus retroflexus L.), white clover (Trifolium repens L.), and yellow nutsedge (Cyperus esculentus L.). All ASD treatments significantly reduced weed viability compared to the non-treated control. The yeast amendments enhanced weed control over ASD without yeast. The second set of greenhouse trials was focused on ASD using brewer`s spent grain, and on evaluating ASD at the half and one-third carbon dose rates. The target pests were the same weed species in the first set of trials, and Pythium irregulare was added as an additional target pest. This set of trials indicated yeast enhanced addition the effect of BSG in ASD on both weeds and P. irregulare, indicating the potential to reduce carbon input necessary for effective ASD. A follow-up, two seasons, open-field trial conducted over two growing seasons at the Hampton Roads AREC focused on understanding the effects of ASD on weed density and strawberry fruit yield and fruit quality in annual hill strawberry production. The treatments included ASD at standard or half carbon dose rates, with or without yeast. Fumigation (80% chloropicrin + 20% 1,3-dichloropropene) and non-treated plots were used as control groups. Weed suppression with ASD was consistent for most of the broadleaf weed species, and total weed counts were significantly reduced compared to non-treated controls. Yield from ASD with yeast was higher than ASD without yeast and non-treated control in one growing season, while the increase in yield did not occur in another growing season. Yeast may have potentially enhanced the yield effects of ASD but lacked consistency. Yeast may have the potential to enhance ASD effectiveness. / Doctor of Philosophy / Strawberry is a high-value crop known for its brightly colored, sweet tasting, juicy and fleshy fruit that possesses a unique aroma. The southern region is the second large region of strawberry production in the United States. Strawberry is susceptible to soil-borne pests, including weeds and diseases. Preplant control of soil-borne diseases and weeds is important for strawberry production. Early season weeds can compete with newly transplanted strawberry plugs for nutrients, light, and other resources. However, currently, the limited options of pre-plant chemical fumigants and herbicides available in strawberry plasticulture make weed control a challenge in strawberry production. Anaerobic soil disinfestation (ASD) may be an effective alternative to preplant chemical fumigation. Anaerobic soil disinfestation involves three steps- applying carbon sources to the soil, covering the bed with black tarp, and watering the soil to maintain certain soil moisture to field capacity generally for 21 days. However, there are only a few studies on weed control using ASD in the southern region; locally available carbon sources also need to be evaluated. Thus, this study focused on evaluating several locally available carbon sources (cover crops, brewer`s spent grain, used coffee ground, paper mulch, peanut shell) for ASD to control troublesome weeds (common chickweed, redroot pigweed, white clover, yellow nutsedge). This study also explored a new method that involves mixing distiller's yeast with solid carbon sources in order to enhance the ASD weed control effect. Additionally, this study evaluated the effect of ASD using reduced carbon inputs, potentially reducing the total cost of ASD by reducing the carbon input. A series of greenhouse studies were conducted at the Southern Piedmont Agricultural Research and Extension Center (AREC), Blackstone, VA, with a follow-up field study done at the Hampton Roads AREC. The greenhouse trials evaluated carbon sources including brewer`s spent grain, buckwheat, cowpea, paper mulch, peanut shells, rice bran, sorghum-sudangrass, and waste coffee grounds. These greenhouse experiments were conducted in containers made from PVC tubes, and strawberry plants were not involved. The main objective of the greenhouse trial was to test the suppression of four troublesome weeds, including common chickweed, redroot pigweed, yellow nutsedge, and white clover. The most effective treatments in the greenhouse studies were further investigated in the field trial. The brewer`s spent grain was again used in the field trial, and treatments included ASD using a full or half dose of brewer's spent grain, with or without yeast. We evaluated the effects of these treatments on weed control, plant crop growth, and crop yields. Fruit quality factors, including fruit firmness, sweetness, and size, were also evaluated. In summary, all of the carbon sources evaluated provide similar weed control. Adding yeast showed potential to enhance the effect of ASD using brewer`s spent grain. Adding yeast also increased the effectiveness of the half-rate of the carbon source, showing the potential for effective pre-plant pest control for strawberry using ASD treatments with significantly reduced C dose rates.