Ethel M. Doidge's thesis is placed on the UIR in 2013 to celebrate 140 years of university education in South Africa. She was the first women to receive a D.Sc. from Unisa'a predecessor, the University of the Cape of Good Hope in 1914 / This thesis researched a mango disease which caused considerable loss to mango growers in South Africa at the beginning of the twentieth century, particularly around Barberton, Warm baths and the coastal region of Natal. The disease caused dark angular spots on the leaves. This did not noticeably affect the general health of the tree, but served as a source of infection for the fruit. The infected fruit is detached from the tree by the slightest air movement and falls rotting to the ground. The infection is carried by wind and rain. Several spraying experiments were carried out at Barberton in an orchard placed at the author's disposal by Messrs Winter Brothers during an exceptionally dry season, which showed that spraying with Bordeaux mixture, iron sulphide or Hyco/ was useless in checking the disease. The disease had not been described in the literature before. According to the author, the cause of the disease was a flagellate bacillus Bacillus mangiferae. It invades the parenchyma, wedging apart and killing the cells and causing gummosis, but it does not touch the lignified tissues. The organism is described, and was tested in detail in laboratory experiments and a resume of its salient characters is given in the thesis / Agriculture and  Animal Health / D.Sc. (Botany)

This dissertation illuminates how phytosanitary (PS) regulations enable mango exportation from Mexico to the United States. PS regulations are technical and legal measures to prevent plant pests from proliferating or being transported to other places and are important regulatory mechanisms enabling the globalization of agriculture. My case study investigates how PS regulations enable Mexican mango exportation as an aspect of the globalization of agriculture, illustrating the consequences of PS regulations to humans and non-humans. More specifically, three research questions are posed: (1) How does the PS regulation network operate to draw distinctions between pest/non-pest, thereby enabling the export of Mexican mangos to the United States? (2) What values are associated with the PS regulation network, and what are the normative, moral, or ethical implications of the regulations? And, (3) How are the PS regulations in transition in the state of Sinaloa changing economic prospects for mango growers and packers to tap into global mango markets? Theoretically, the analysis draws on a concept called “material politics,” which claims that politics is enacted through not only discursive measures, such as statutes, but also physical embodiment by material beings. Thus, PS regulations are conceptualized as a materially heterogeneous network that establishes boundaries between pest/non-pest, thereby connecting distinct places, such as mango orchards and consumers. The material politics concept also suggests the emergence of socio-material “ordering” effects by regulations, such as values, morals, and norms, as well as unequal economic opportunities. Nine months of ethnographic fieldwork in Mexico, which employed in-depth interviews, (participant) observations, and documentary research, yielded the following findings: (1) PS regulations as a network of governance (re)configured the production of the commodity, “disciplining” humans and non-humans to conform to the global regulatory order; (2) in this network, non-governmental entities played critical roles, fitting squarely with the recent neoliberal political-economic orientation in Mexico; and (3) although the government’s pest eradication program could improve market chances for growers, local political-economic circumstances, including small-scale growers’ dependence on packers for marketing, still left substantial challenges for such economic prospects to materialize.

Ethel M. Doidge's thesis is placed on the UIR in 2013 to celebrate 140 years of university education in South Africa. She was the first women to receive a D.Sc. from Unisa'a predecessor, the University of the Cape of Good Hope in 1914 / This thesis researched a mango disease which caused considerable loss to mango growers in South Africa at the beginning of the twentieth century, particularly around Barberton, Warm baths and the coastal region of Natal. The disease caused dark angular spots on the leaves. This did not noticeably affect the general health of the tree, but served as a source of infection for the fruit. The infected fruit is detached from the tree by the slightest air movement and falls rotting to the ground. The infection is carried by wind and rain. Several spraying experiments were carried out at Barberton in an orchard placed at the author's disposal by Messrs Winter Brothers during an exceptionally dry season, which showed that spraying with Bordeaux mixture, iron sulphide or Hyco/ was useless in checking the disease. The disease had not been described in the literature before. According to the author, the cause of the disease was a flagellate bacillus Bacillus mangiferae. It invades the parenchyma, wedging apart and killing the cells and causing gummosis, but it does not touch the lignified tissues. The organism is described, and was tested in detail in laboratory experiments and a resume of its salient characters is given in the thesis / Agriculture and  Animal Health / D.Sc. (Botany)

This master-thesis presents an approach to track and count the number of fruit incommercial mango orchards. The algorithm is intended to enable precision agri-culture and to facilitate labour and post-harvest storage planning. The primary objective is to develop an multi-view algorithm and investigate how it can beused to mitigate the effects of visual occlusion, to improve upon estimates frommethods that use a single central or two opposite viewpoints. Fruit are detectedin images by using two classification methods: dense pixel-wise cnn and regionbased r-cnn detection. Pair-wise fruit correspondences are established between images by using geometry provided by navigation data, and lidar data is used to generate image masks for each separate tree, to isolate fruit counts to individual trees. The tracked fruit are triangulated to locate them in 3D space, and spatial statistics are calculated over whole orchard blocks. The estimated tree counts are compared to single view estimates and validated against ground truth data of 16 mango trees from a Bundaberg mango orchard in Queensland, Australia. The results show a high R2-value of 0.99335 for four hand labelled trees and a highest R2-value of 0.9165 for the machine labelled images using the r-cnn classifier forthe 16 target trees.

Master of Science / Food Science Institute, Human Nutrition / Delores H. Chambers / Fresh mangoes are highly perishable, and therefore, they are often processed to extend shelf-life and facilitate exportation. Studying the transformation that mango cultivars undergo throughout processing can aid in selecting appropriate varieties for products. In the 1st part of this study, the flavor and texture properties of 4 mango cultivars available in the United States (U.S.) were analyzed. Highly trained descriptive panelists in the U.S. evaluated fresh, purée, and sorbet samples prepared from each cultivar. Purées were made by pulverizing mango flesh, passing it through a china cap, and heating it to 85 °C for 15 s. For the sorbets, purées were diluted with water (1:1), sucrose was added, and the bases were frozen in a batch ice cream freezer. Much of the texture variation among cultivars was lost after fresh samples were transformed into purées, whereas much of the flavor and texture variation among cultivars was lost once fresh mangoes and mango purées were transformed into sorbets. Compared to the other cultivars, Haden and Tommy Atkins underwent greater transformations in flavor throughout sorbet preparation, and processing reduced the intensities of some unpleasant flavors in these cultivars. Tommy Atkins was the only cultivar that had flavor differences from other cultivars when it was in sorbet. Results suggest that cultivar variation is generally not detectable in mango sorbet unless the cultivar has a distinct initial flavor. In the 2nd part of this study, descriptive panelists in Thailand evaluated the flavor and texture properties of fresh samples and purées prepared from 6 cultivars grown in Thailand. Thermal processing had unique effects on the flavor of each cultivar, especially Nam Dok Mai and Chok Anun; Nam Dok Mai significantly decreased in mango identity and peach flavors after processing, whereas Chok Anun significantly increased in sweet, mango identity, and pineapple flavors. Although a slight amount of flavor variation among cultivars was lost because of thermal processing, most of the texture variation was eliminated. Because of significant changes in flavor and texture after heat treatment of mango cultivars, manufacturers should select cultivars for mango purées based on their properties after thermal processing.

A constante preocupação com o aumento do uso de agrotóxicos nas lavouras e os riscos gerados pelos resíduos destes compostos fazem com que os órgãos responsáveis pela fiscalização de alimentos no Brasil controlem a presença dessas substâncias nos produtos que chegam à mesa do consumidor. Atualmente, um dos grandes problemas na produção de alimentos é a utilização de substâncias proibidas em lavouras, muitas das quais não possuem estudos nem limites máximos de resíduos (LMR) estabelecidos, assim como a utilização de substâncias já registradas, mas em quantidades ou métodos de manejo incorretos. Ambos os casos podem resultar em sérios problemas à saúde humana. O objetivo deste estudo foi a avaliação da determinação de morfolina em amostras de manga utilizando técnicas como a Extração em Fase Sólida e a Cromatografia Gasosa acoplada à Espectrometria de Massas (SPE-GC-MS), assim como a Microextração em Sorvente Empacotado e Cromatografia Gasosa acoplada à Espectrometria de Massas (MEPS-GC-MS). Um segundo objetivo deste estudo consistiu em desenvolver, validar e avaliar uma metodologia analítica capaz de identificar quantitativamente a morfolina em amostras de manga por Cromatografia Líquida de Ultra Eficiência acoplada a Espectrometria de Massas em tandem (UHPLC-MS/MS). Para análise por GC-MS fez-se necessária a etapa de derivatização do analito, de forma que o mesmo aumentasse sua volatilidade e diminuísse a polaridade. A comparação entre as técnicas SPE e MEPS não foi possível devido ao efeito de matriz causado pela contaminação do liner e da coluna cromatográfica. Já a metodologia validada por UHPLC-MS/MS seguiu os critérios exigidos pelo Manual de Garantia da Qualidade Analítica, do Ministério da Agricultura Pecuária e Abastecimento (MAPA). O método foi aplicado em mangas de diferentes variedades obtidas no comércio local. Não foram encontrados resíduos de morfolina em nenhuma das amostras investigadas, de acordo com a metodologia proposta. Os resultados apresentados neste trabalho estabelecem metodologias eficientes, rápidas e de baixo custo na determinação de morfolina em amostras de manga. / The recurrent increasing of the use of pesticides on crops and the consequent risks due the exposure to chemical residues have urged the food regulation agencies to control the levels of these substances in products that reach consumer\'s table. A major problem nowadays for the production of food is the use of banned substances in crops and the extrapolation of the limit dosages of substances, which may result in serious problems to human health. Furthermore, many of these substances commonly used in crops still lack substantial information about the maximum residue levels (MRLs). The aim of this study was the evaluation of morpholine levels in mango samples using distinct techniques such as Solid Phase Extraction followed by Gas Chromatography coupled to Mass Spectrometry (SPE-GC-MS) and Microextraction by Packed Sorbent followed by Gas Chromatography Mass Spectrometry (MEPS-GC-MS). Another main goal of this work is the development, validation and evaluation of an analytical methodology to identify and quantitfy the presence of morpholine in mango samples, using Ultra-High Performance Liquid Chromatography coupled to tandem Mass Spectrometry (UHPLC-MS/MS). For the analysis of samples by GC-MS, it was required an initial step of derivatization of the analyte, in order to increase its volatility and reduce polarity. The comparison between SPE and MEPS techniques could not be performed due to matrix effects caused by contamination of the liner and the chromatographic column. On the other hand, the validated methodology for UHPLC-MS/MS presented herein followed all requirements proposed by the Analytical Quality Assurance Manual, accordingly to the Ministry of Agriculture, Livestock and Food Supply from Brazil. This method was applied in mango sample belonging to a wide variety of species found in the city of São Carlos, SP. Nevertheless, no significant levels of morpholine residues were found in any of the samples. In this work, we established a methodology efficient, fast and low cost for the determination of morpholine in mangos.

A manga (Mangifera indica L.) é uma fruta tropical de origem no continente asiático e umas das principais frutas comercializadas no mundo. A mangicultura apresenta potencial para expandir ainda mais a comercialização de frutos e derivados principalmente, com qualidades para exportação. A produção mundial em média é de 27 milhões de toneladas. Os programas de melhoramento de mangueira necessitam desenvolver cultivares que apresentem o maior número de características agronômicas agregadas. O conhecimento da variabilidade e estrutura genética é almejado pelos melhoristas uma vez que a espécie é perene e apresenta longo o período para obtenção de novas cultivares. Neste trabalho, 151 acessos de mangueira foram analisados quanto a diversidade e estrutura genética do banco de germoplasma. Foram desenvolvidos 23 marcadores microssatélites para caracterização do banco de germplasma de mangueira. Os locos microssatélites apresentaram alto poder informativo para estudos populacionais e observaram-se médias da heterozigosidade esperada de He=0,655, heterozigosidade observada de Ho=0,496 e de PIC = 0,621. Posteriormente a partir dos dados moleculares foram estimados a diversidade e estrutura genética dos 151 acessos e observaram-se 144 alelos com média de 7,2 alelos por loco com amplitude entre 2 e 12 alelos, e uma diversidade gênica média de 0,689. Em todas as simulações estatísticas utilizadas houve consistência em se agrupar os acessos em dois grupos, um grupo formado pelos acessos brasileiros e outro com os acessos norte americanos e os novos híbridos. Uma coleção nuclear foi formada com 30 acessos conseguindo manter 100% dos alelos considerando a diversidade molecular dos 151 acessos de mangueira. Para disponibilizar mais informações ao banco de germoplasma de mangueira da EMBRAPA, 103 acessos contendo informações de 20 locos microssatélites e médias de 48 características agromorfológicas foram avaliadas em conjunto pelo método de otimização de Tocher e formaram-se 23 grupos, onde mais de 50% dos acessos formaram 22 grupos; destes, 10 grupos foram formados por acesso único. Com a finalidade de gerar mais informações para programas de melhoramento da mangueira, um teste de atribuição foi realizado a partir dos dados moleculares e fenotípicos qualitativos, em que também os acessos foram agrupados em dois grandes grupos. / The mango (Mangifera indica L.) is a tropical fruit of Asiatic origin and one of the main fruits traded worldwide. The mango crop presents a potencial for further expansion of fruits and derivative trades mainly export qualities. The average world production is 26 million tons. Breeding programs need to develop mango cultivars having the highest aggregate number of agronomic traits. Knowledge of both the genetic variability and structure is aimed by mango culture breeders due to perennial species as well as to the long period of time to obtain new cultivars. In this study, the genetic diversity and structure of the germplasm bank in 151 acessions of mango were analyzed. At first, 23 microsatellite markers were developed in order to extract molecular information from bank germplasm. It was possible to detect that the SSR loci were highly informative in the studied population. Averages were obtained of He = 0.655, Ho = 0.496 and PIC = 0.621. Next, with the molecular data it was possible to estimate the genetic diversity and structure of the 151 acessions as well as observe 144 alleles with an average of 7.2 per locus with amplitude between 2 and 12 alleles; the average gene diversity was 0.689. In all simulations there were consistent statistic analyzes enabling the clustering cultivars in two groups. A group was formed by Brazilian landraces and a second group was formed by North American landraces and Brazilian new hybrids. A core collection of 30 acessions was able to keep 100% of the alleles representing the molecular diversity of 151 mango cultivars. To provide more information to the Embrapa germplasm mango tree, 103 acessions containing information from 20 microsatellite loci and average of 48 agronomic traits were assessed together by the method of Tocher and formed 23 groups. Twenty two groups were formed by more than 50% of acessions while 10 groups were formed by a single acession each. An interactive test was conducted from molecular and qualitative phenotype data which resulted in two consistent clusters.

A manga é um fruto ainda considerado exótico, onde quase tudo relativo ao seu amadurecimento está por ser esclarecido. Pouco se conhece da sua fisiologia e bioquímica pós colheita. Os objetivos deste trabalho foram avaliar algumas variedades de mangas durante o crescimento e amadurecimento; quanto aos açúcares solúveis, amido e ácido ascórbico; a atividade das enzimas sacarose-fosfato sintase e sacarose sintase durante este mesmo período na manga Van Dyke e o perfil de respiração e etileno das variedades Van Dyke, Tommy Atkins e Haden após a colheita. Os resultados mostraram que os perfis dos açúcares solúveis relativos ao adoçamento e seu metabolismo são altamente dependentes do cultivar e da maturidade fisiológica da manga. A sacarose foi o açúcar predominante em todas as variedades analisadas, sendo que o maior valor encontrado foi de aproximadamente 5% na manga Van Dyke. A frutose foi a hexose predominante na manga madura, e sua relação com a glicose variou de 2,5 a 48 vezes. Os teores de amido existentes quando a manga é colhida, independente da variedade, são muito baixos, menores que 3,0%. As enzimas ligadas ao metabolismo da sacarose, saca rose-fosfato sintase (SPS) e sacarose sintase (SS), tiveram a atividade aumentada na fase de amadurecimento pós colheita no cultivar Van Dyke. O teor de ácido ascórbico, na maioria das variedades diminuiu antes da colheita, exceto a manga Keitt e a manga Tommy Atkins, sendo esta a que apresentou maior teor de ácido ascórbico no fruto maduro. Não houve produção de etileno após o ponto de colheita, e foi encontrado mais de um pico de respiração nas mangas Haden e Van Dyke, resultado atípico de outros frutos climatéricos. / The mango ripening process and the associated physiological and biochemical changes is still poorly known. Also is unknown if the bulk of sugar is accumulated prior or after the onset of ripening. The aim of this work was to evaluate the soluble sugars, starch and ascorbic acid content during the growth and ripening of several mango varietes. The sucrose-phosphate synthase (SPS) and sucrose synthase (SS) activities were evaluated in Van Dyke mango variety. The post harvest respiration and ethylene profiles of the Van Dyke, Tommy Atkins and Haden varieties were analyzed after harvesting. The results shown that the changes on total sugar profiles were highly dependent on the cultivar and physiogical maturity. Sucrose was the predominant sugar in ali analyzed varieties. The fructose amount was 2,5 to 48 times higher than glucose being the predominant hexoses in ripe fruit. The starch content of any variety of harvested mango is too low, with values under 3,0%. The sucrose related enzymes (SPS and SS), showed an increasing activity during the post-harvest ripening of Van Dyke\'s cultivar. For most varieties, the ascorbic acid content decreased before the harvest point, except for Keitt and Tommy Atkins mangos. The highest ascorbic acid content was found in the ripened Tommy fruit. One increase in the ethylene was not detected after harvesting. More than one respiration peak was detected for Haden and Van Dyke\'s varieties, this result is different of the other climacteric fruit\'s one.

O desenvolvimento e o amadurecimento de frutos são processsos complexos e organizados, ondeo fitormônios, como o ácido indol-3-acético (AIA), o ácido abscísico (ABA) e o etileno desempenham papel relevante. Dentro os processos característicos do amadurecimento, a degradação do amido apresenta impacto direto sobre a qualidade da manga, sendo practicamente todo degradao a síntese de sacarose. Várias enzimas participam da degradação do grânulo de amido, como também em bananas. A mobilização do amido em mangas Keitt parece estar dissociada temporalmente da evolução do etileno; e as variações nos níveis de AIA e ABA sugerem um possível papel na sinalização para mobilização do amido. A biossíntese da sacarose foi atrasada pelo 1-MCP, um antagonista do etileno, sugerindo redução na velocidade do fluxo de carbono do amido para síntese da sacarose que pode ser, resultante das alterações no metabolismo da maltose proveniente da degradação do amido. / The fruit development and ripening are organized and complex processes where phytohormones, like indol-3-acetic acid (IAA), abscisc acid (ABA) and ethylene have a pivotal role. In mango fruit one of the main metabolisms that have direct impact in the mango quality is the starch degradation, practically being all degrated the synthesis of sacarose. Some enzymes participate of the degradation, as hidrolases (alfa and beta-amylases, disproportionating enzymes) and phosphorylases, described also in bananas. The mobilization of the starch in Keitt mangoes it does not seem to be temporally associated with ethylene; and variations in the IAA and ABA levels suggest their possible role in the signalling for the starch. Sucrose biosynthesis was delayed by 1-MCP indicating a reduction in the speed of the carbon flux from the starch that it can be, resultant of the alterations in the metabolism of maltose provenient from the starch degradation.

A manga (Mangifera indica L.) é cultivada em áreas tropicais e subtropicais, principalmente em países em desenvolvimento. Os maiores produtores são a Índia, China, México, Indonésia, Tailândia, Paquistão e Brasil, mas, por ser uma fruta altamente perecível, suas exportações têm sido limitadas. Durante o amadurecimento, as frutas adquirem características que as tornam adequadas para o consumo como conseqüência de alterações metabólicas dependentes, em larga medida, da expressão de genes específicos. Uma vez que as proteínas são os elementos efetores da expressão gênica, a análise de proteomas pode auxiliar na identificação de pontos de controle do metabolismo determinantes para a qualidade desses alimentos. Assim, o objetivo do trabalho é identificar spots de proteínas diferentemente abundantes durante o amadurecimento a partir dos mapas 2D-DIGE das polpas de mangas (Mangifera indica L.) da cultivar Keitt nos estádios pré-climatérico e climatérico. Após extração das proteínas e separação por 2D-DIGE, as imagens dos géis obtidas foram analizadas com o software PDQuest, utilizando o teste T de Student para a análise estatística. Dentre os spots protéicos bem resolvidos e considerados na análise, os 47 que apresentaram-se diferentemente abundantes entre os estádios estudados foram removidos dos géis, suas proteínas digeridas e, enfim, sequenciadas por espectrometria de massas. Foram obtidas as identidades prováveis de 58 proteínas diferentes a partir da comparação das sequencias obtidas com banco de dados NCBI2010, utilizando o software Mascot. / Mango fruit (Mangifera indica L.) is cultivated in tropical and subtropical areas, mainly in developing countries. India, China, Mexico, Indonesia, Thailand, Pakistan and Brazil are the major producers, but its trade has been limited due the highly perishable nature of the fruit. During ripening, the fruits acquire characteristics that make them appropriate for consumption as a consequence of metabolic changes dependent on the expression of specific genes. As proteins are the effector elements of gene expression, proteome analysis can help the identification of metabolism keypoints that could influence the fruit quality. Thus, the aim of this study was to compare the protein maps of mango pulp (Mangifera indica L. cv. Keitt) in pre-climacteric and climacteric stages, in order to identify protein spots that differ in abundance in these two stages. After protein extraction and separation by 2D-DIGE technique, the gel images obtained were analyzed with PDQuest software, using the Student´s T-test for statistical analysis. We obtained 47 spots differently abundant between the stages studied, that were excised from the gels and its proteins digested with trypsin and sequenced by mass spectrometry. We obtained the identities of 58 distinct proteins from the search of the peptide sequences against NCBI2010 database using the software Mascot.