Senegal ranks second for mango production among West African countries and has the potential to competitively produce mangoes for the European market. Colletotrichum gloeosporioides Penz. and Sacc. has historically been considered the causal pathogen of anthracnose of mango and other fruits, but is now known to represent a species complex. Field trials to examine the efficacy of fungicides and biofungicides were conducted in southern and northern production regions of Senegal. In three southern trials, Sonata (Bacillus pumilus strain QST 2808), Serenade Optimum (Bacillus subtilis strain QST 713), and sodium molybdate provided 63%, 67% and 76% control of disease severity, respectively, whereas thiophanate methyl and azoxystrobin provided 77% and 78% control, respectively. Disease severities of all treatments were significantly lower than that of the control. Thiophanate methyl and azoxystrobin produced more disease-free mangoes (64 and 62%, respectively) than Serenade (49%), sodium molybdate (44%), and Sonata (38%). Differences within each trial were not statistically significant, but when all trials were combined, all treatments resulted in significantly more disease-free mangoes than the control. Among treatments, thiophanate methyl and azoxystrobin resulted in significantly more disease-free mangoes than Sonata. No results were obtained in the northern orchards due to an absence of disease development. Sequencing of the ITS gene region of 30 Colletotrichum isolates from mangoes from different regions in Senegal indicated that all belonged to the C. gloeosporioides species complex. Sequencing of the ApMat intergenic region identified all of them as most closely resembling C. siamense. / Master of Science in Life Sciences

Tesis por compendio / [ES] La presente tesis doctoral tiene como principal objetivo el desarrollo de materiales poliméricos que sean respetuosos con el medio ambiente y favorezcan modelos de economía circular, centrando las líneas de investigación en el reaprovechamiento de residuos de la industria del mango y en la utilización de ácido poliláctico (PLA) como principal matriz polimérica. Para ello se emplean diferentes técnicas de procesado como el electrospinning, la extrusión, la inyección o la producción de films por disolución. Además, se plantea la utilización de diferentes aditivos como plastificantes y cargas lignocelulósicas de origen renovable para mejorar las propiedades de estos materiales sin comprometer su alto potencial medioambiental. El primer bloque de la tesis centra sus esfuerzos en el reaprovechamiento de diferentes residuos del mango (uno de los cultivos más populares del mundo), como la piel y el kernel, para desarrollar diferentes materiales con un gran contenido natural. Dentro de los estudios realizados en este bloque se incluye la extracción de almidón a partir del kernel de mango para la posterior fabricación de nanofibras por electrospinning, con gran aplicación en el sector médico. Otros estudios realizados proponen la combinación de matrices poliméricas como el biopolipropileno y el PLA, en combinación con harina de piel de mango y harina de hueso de mango, respectivamente, mediante procesos de extrusión, extrusión reactiva (REX) e inyección. En el caso del biopolipropileno se utilizan además agentes compatibilizantes basados en ácido itacónico para aumentar la adhesión entre las partículas lignocelulósicas de la piel del mango con la matriz polimérica, la cual es altamente apolar. Por otro lado, a las formulaciones de PLA y harina de hueso de mango se le añaden plastificantes como la triacetina y la tributirina para aumentar las propiedades dúctiles del PLA. Un cuarto estudio se enfoca en la producción de films de glicerol con harina de hueso de mango, rica en almidón, para observar cómo afecta el tamaño de partícula de la harina sobre las propiedades de los films. Por último, se propone el desarrollo de materiales termoplásticos ricos en almidón utilizando harina de kernel de mango en combinación con diferentes plastificantes como glicerol, sorbitol y urea. Estos materiales ricos en almidón son procesados por extrusión e inyección y son completamente biodegradables y de origen natural. El segundo y último bloque de la tesis está enfocado a la utilización del ácido poliláctico obtenido de fuentes renovables en procesos de extrusión e inyección. Este poliéster es un polímero biodegradable cuya principal desventaja es su gran fragilidad. Por ello, se han empleado diferentes tipos de plastificantes naturales para incrementar las propiedades dúctiles del PLA. En un primer trabajo, se combina el PLA con α-terpinil acetato, un plastificante de origen renovable. Además, se añade piel de mandarina molida como carga natural para evaluar si este plastificante es capaz de aumentar la ductilidad de mezclas de PLA con cargas lignocelulósicas, obtenido resultados muy positivos. Un segundo trabajo plantea la combinación de PLA con dietil-L-tartrato, un plastificante obtenido del ácido tartárico, encontrado en la uva y el tamarindo, obteniendo elongaciones de más de un 300%. Por último, dos estudios más plantean la combinación de PLA con terpenoides, más concretamente ésteres de geranilo y linalilo. En este sentido, uno de los trabajos se centra en variar la proporción de acetato de linalilo y acetato de geranilo en las composiciones, mientras que el otro trabajo evalúa como afecta la longitud de cadena de los ésteres de geranilo a la plastificación del PLA. Todos los plastificantes utilizados en este bloque ofrecieron resultados muy prometedores, con alargamientos a la rotura superiores al 200% en materiales completamente naturales y biodegradables con gran aplicación en el sector alimentario y del envase y embalaje. / [CA] La present tesi doctoral té com a principal objectiu el desenvolupament de materials polimèrics que siguen respectuosos amb el medi ambient i afavorisquen models d'economia circular, centrant les línies d'investigació en el reaprofitament de residus de la indústria del mango i en la utilització d'àcid polilàctic (PLA) com a principal matriu polimèrica. Per a això s'empren diferents tècniques de processament com l'electrospinning, l'extrusió, la injecció o la producció de films per dissolució. A més, es planteja la utilització de diferents additius com a plastificants i càrregues lignocelulòsiques d'origen renovable per a millorar les propietats d'aquests materials sense comprometre el seu alt potencial mediambiental. El primer bloc de la tesi centra els seus esforços en el reaprofitament de diferents residus del mango (un dels cultius més populars del món), com la pell i el kernel, per a desenvolupar diferents materials amb un gran contingut natural. Dins dels estudis realitzats en aquest bloc s'inclou l'extracció de midó a partir del kernel de mango per a la posterior fabricació de nanofibers per electrospinning, amb gran aplicació en el sector mèdic. Altres estudis realitzats proposen la combinació de matrius polimèriques com el biopolipropilè i el PLA, en combinació amb farina de pell de mango i farina d'os de mango, respectivament, mitjançant processos d'extrusió, extrusió reactiva (REX) i injecció. En el cas del biopolipropilè s'utilitzen a més agents compatibilitzants basats en àcid itacònic per a augmentar l'adhesió entre les partícules lignocelulòsiques de la pell del mango amb la matriu polimèrica, la qual és altament apolar. D'altra banda, a les formulacions de PLA i farina d'os de mango se li afigen plastificants com la triacetina i la tributirina per a augmentar les propietats dúctils del PLA. Un quart estudi s'enfoca en la producció de films de glicerol amb farina d'os de mango, rica en midó, per a observar com afecta la grandària de partícula de la farina sobre les propietats dels films. Finalment, es proposa el desenvolupament de materials termoplàstics rics en midó utilitzant farina de kernel de mango en combinació amb diferents plastificants com glicerol, sorbitol i urea. Aquests materials rics en midó són processats per extrusió i injecció i són completament biodegradables i d'origen natural. El segon i últim bloc de la tesi està enfocat a la utilització de l'àcid polilàctic obtingut de fonts renovables en processos d'extrusió i injecció. Aquest polièster és un polímer biodegradable el principal desavantatge del qual és la seua gran fragilitat. Per això, s'han emprat diferents tipus de plastificants naturals per a incrementar les propietats dúctils del PLA. En un primer treball, es combina el PLA amb α-terpinil acetat, un plastificant d'origen renovable. A més, s'afig pell de mandarina molta com a càrrega natural per a avaluar si aquest plastificant és capaç d'augmentar la ductilitat de mescles de PLA amb càrregues lignocelulòsiques, obtenint resultats molt positius. Un segon treball planteja la combinació de PLA amb dietil-L-tartrat, un plastificant obtingut de l'àcid tartàric, trobat en el raïm i el tamarinde, obtenint elongacions de més d'un 300%. Finalment, dos estudis més plantegen la combinació de PLA amb terpenoids, més concretament èsters de geranil i linalil. En aquest sentit, un dels treballs se centra en variar la proporció d'acetat de linalil i acetat de geranil en les composicions, mentre que l'altre treball avalua com afecta la longitud de cadena dels èsters de geranil a la plastificació del PLA. Tots els plastificants utilitzats en aquest bloc van oferir resultats molt prometedors, amb allargaments al trencament superiors al 200% en materials completament naturals i biodegradables amb gran aplicació en el sector alimentari i de l'envàs i embalatge. / [EN] The present doctoral thesis has as its main objective the development of polymeric materials that are environmentally friendly and promote circular economy models, focusing research on the reuse of waste from the mango industry and the use of polylactic acid (PLA) as the main polymer matrix. Various processing techniques such as electrospinning, extrusion, injection, or cast film are employed for this purpose. In addition, the use of different additives such as plasticizers and lignocellulosic fillers of renewable origin is proposed to improve the properties of these materials without compromising their high environmental potential. The first part of the thesis focuses on the reuse of various mango waste products (one of the most popular crops in the world), such as peel and kernel, to develop different materials with a high natural content. Studies in this section include the extraction of starch from mango kernels for the subsequent production of nanofibers by electrospinning, which have significant applications in the medical sector. Other studies propose the combination of polymeric matrices such as biopolypropylene and PLA, in combination with mango peel flour and mango kernel flour, respectively, through extrusion, reactive extrusion (REX), and injection processes. In the case of biopolypropylene, compatibilizing agents based on itaconic acid are also used to increase the adhesion between lignocellulosic particles from mango peel and the highly apolar polymer matrix. On the other hand, PLA formulations with mango kernel flour are supplemented with plasticizers such as triacetin and tributyrin to enhance the ductile properties of PLA. A fourth study focuses on the production of glycerol films with mango kernel flour, rich in starch, to observe how the particle size of the flour affects the film properties. Finally, the development of starch-rich thermoplastic materials is proposed using mango kernel flour in combination with different plasticizers such as glycerol, sorbitol, and urea. These starch-rich materials are processed by extrusion and injection and are completely biodegradable and of natural origin. The second and final part of the thesis is focused on the use of polylactic acid obtained from renewable sources in extrusion and injection processes. This biodegradable polyester has the main disadvantage of being very brittle. Therefore, different types of natural plasticizers have been used to increase the ductile properties of PLA. In the first study, PLA is combined with α-terpinyl acetate, a renewable plasticizer. In addition, ground tangerine peel is added as a natural filler to evaluate if this plasticizer can increase the ductility of PLA blends with lignocellulosic fillers, yielding very positive results. A second study proposes the combination of PLA with diethyl-L-tartrate, a plasticizer obtained from tartaric acid, found in grapes and tamarind, resulting in elongations of more than 300%. Finally, two more studies propose the combination of PLA with terpenoids, specifically geranyl and linalyl esters. In this regard, one of the works focuses on varying the proportion of linalyl acetate and geranyl acetate in the compositions, while the other study evaluates how the chain length of geranyl esters affects PLA plasticization. All the plasticizers used in this section offered very promising results, with elongations at break exceeding 200% in completely natural and biodegradable materials with significant applications in the food and packaging sectors. / This research is a part of the grant PID2020-116496RB-C22, funded by MCIN/AEI/10.13039/501100011033 and the grant TED2021-131762A-I00, funded by MCIN/AEI/10.13039/501100011033 and by the European Union “NextGenerationEU”/PRTR. Authors also thank Generalitat Valenciana-GVA for funding this research through the grant numbers AICO/2021/025 and CIGE/2021/094. Funded with Aid for First Research Projects (PAID-06-22), Vice-rectorate for Research of the Universitat Politècnica de València (UPV). J. I.-M. wants to thank FPU19/01759 grant funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. J. G.-C. wants to thank FPU20/01732 grant funded by MCIN/AEI/10.13039/ 501100011033 and by ESF Investing in your future. / Gómez Caturla, J. (2024). Desarrollo y caracterización de polímeros de alto rendimiento medioambiental derivados de residuos agroindustriales y aditivos de origen renovable [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203217 / Compendio

No presente trabalho, diferentes condições de pasteurização foram estudadas a fim de desenvolver um purê de manga para pronto consumo, sem adição de açúcares e de conservantes, com estabilidade microbiológica, físico-química e sensorial. A qualidade e a vida de prateleira do purê foram avaliadas por meio de análises físico-químicas, microbiológicas, enzimáticas, reológicas e sensoriais. Na primeira etapa do trabalho, foram estudadas temperaturas de pasteurização entre 65 e 85 °C, em trocador de calor a placas e tubular. Os ensaios mostraram que o trocador tubular foi o mais indicado para a pasteurização do purê de manga. A inativação térmica da peroxidase, uma das enzimas mais termorresistentes encontradas naturalmente em mangas, foi utilizada como parâmetro de pasteurização. Os parâmetros cinéticos para inativação da enzima foram calculados: D77,2 ºC e z iguais a 4,4 s e 14,3 ºC, respectivamente. Na segunda etapa, duas condições de pasteurização, P1 (70ºC/13s) e P2 (75 ºC/13s), foram selecionadas para determinação da vida de prateleira do purê. A pasteurização nestas condições, combinada ao armazenamento refrigerado, foi eficiente para manter a qualidade microbiológica, físico-química e sensorial do purê por 17 semanas. Análises microbiológicas indicaram que os maiores contaminantes do purê cru foram os microrganismos mesófilos e os bolores e leveduras. Com a pasteurização, houve redução significativa destes microrganismos e de coliformes fecais. Todas as características físico-químicas (pH, acidez titulável, teor de sólidos totais, sólidos solúveis, ácido ascórbico e cor) foram influenciadas significativamente pelo tempo de armazenamento. Foi observada diferença significativa do pH a partir da 17ª semana de armazenamento e a perda de ácido ascórbico foi de aproximadamente 45 % após 20 semanas. As medidas reológicas mostraram a natureza pseudoplástica do purê de manga: os valores de n variaram entre 0,27 e 0,29 e os valores de K entre 5,00 e 7,16 Pa.sn. O tempo de armazenamento praticamente não influenciou os parâmetros reológicos dos purês pasteurizados. Na análise sensorial, notas superiores a 6,7 foram obtidas, indicando que o produto teve boa aceitação durante as 17 semanas de armazenamento. O tempo de armazenamento não influenciou significativamente os atributos sensoriais, exceto no purê processado na condição P1. / In this work, different pasteurization conditions were studied in order to develop a ready-to-serve mango purée, with microbiological safety and physical-chemical and sensorial stability. Physical-chemical, microbiological, enzymatic and sensory analyses and rheological measurements were carried out to evaluate quality and shelf life of mango purée. Two types of heat exchanger were used to pasteurize mango purée: a plate heat exchanger and a double pipe heat exchanger. Pasteurization temperatures ranged from 65 to 85ºC. The double pipe exchanger showed to be more suitable for the process, due to characteristics of purée. Thermal inactivation of peroxidase, one of most thermostable enzymes naturally present in mangoes, was used as indicator of pasteurization. Kinetic parameters were calculated: D77.2 ºC = 4.4 s and z = 14.3 ºC. Two pasteurization conditions P1 (70 °C / 13s) and P2 (75 °C / 13s) were selected in order to determine shelf life of mango purée. Pasteurization, combined to refrigerated storage, was effective to maintain microbiological, physical, chemical and sensory quality of purée for 17 weeks. Microbiological analysis showed that the main contaminants of raw purée were mesophilic microorganisms and yeast and moulds. After pasteurization, there was significant reduction of these microorganisms and of thermo-tolerant coliforms. All physical-chemical attributes (pH, titratable acidity, total solids, soluble solids, ascorbic acid and color) were affected significantly by storage time. It was observed significant difference in pH after 17 weeks of storage and ascorbic acid loss was approximately 45 % after 20 weeks. Rheological measurements showed shear thinning nature of mango purée: n values varied from 0.27 to 0.29 and K values from 5.00 to 7.16 Pa.sn. Storage time did not affect significantly rheological parameters of pasteurized purées. Sensory analysis of pasteurized mango purée indicated that the product has good acceptance (scores \'> or =\' 6,7) over 17 weeks of refrigerated storage. Storage time did not affect significantly sensory attributes, except color of P1 mango purée.

O Brasil é um dos principais países produtores de abacate. A competitividade do país no comércio internacional desta fruta demanda a minimização de danos pós-colheita, especialmente os causados pela antracnose. Este trabalho objetivou: (i) identificar e quantificar os danos pós-colheita em abacates Fuerte e Hass; (ii) identificar e caracterizar isolados de Colletotrichum do abacateiro, comparando-os com isolados de outras frutíferas; (iii) avaliar o efeito de temperatura e período de molhamento sobre a germinação de conídios e formação de apressórios, bem como, sobre a infecção e colonização de Colletotrichum gloeosporioides em abacates; (iv) avaliar o efeito de fungicidas e sanitizantes no controle da antracnose do abacateiro em pós-colheita. As incidências da antracnose e de outros danos póscolheita foram avaliadas periodicamente em abacates amostrados em três etapas do beneficiamento em packinghouse e revelaram que a antracnose foi a principal doença póscolheita, com incidências média de 45,7% para o abacate Fuerte e 68,7% para Hass. Identificação, caracterização e análise comparativa foram realizadas para 93 isolados obtidos de abacate, manga, maracujá e pêssego, por meio do aspecto da colônia e taxa de crescimento em diferentes temperaturas, formato e dimensões dos conídios, análise molecular (PCR com oligonucleotídeos espécie-específicos e análise de sequências de nucleotídeos das regiões ITS e -tubulina), patogenicidade e atividade enzimática (amilase, catalase, celulase, lacase, lípase, pectinase e proteinase). Todos os isolados de abacate e manga, e alguns isolados de pêssego e maracujá foram identificados como C. gloeosporioides. As espécies C. acutatum e C. boninense foram detectadas em pêssego e maracujá, respectivamente. A análise filogenética associada a algumas características morfo-culturais permitiu a separação das espécies e revelou diferenças intra-específicas entre os isolados de C. gloeosporioides, de acordo com o hospedeiro de origem. Os isolados de manga compuseram um grupo distinto dentro da espécie. Entretanto, independente do hospedeiro de origem, as três espécies de Colletotrichum promoveram infecções cruzadas nos quatro hospedeiros avaliados, indicando a ausência de especificidade patogênica. Para todas as características avaliadas houve alta variabilidade entre os isolados. Germinação de esporos e formação de apressórios de C. gloeosporioides sobre abacates Fuerte incubados a 5, 10, 15, 20, 25, 30, 35 e 40ºC com período de molhamento de 3, 6, 12, 24h revelou que o fungo pode explorar ampla faixa de temperatura, germinando e formando apressórios entre 10 e 35ºC, com temperatura ótima de 23,4ºC e 24,0ºC, respectivamente. Aumento no período de molhamento promoveu maiores percentagens de esporos germinados e formação de apressórios. Os efeitos da temperatura (10, 15, 20, 25, 30ºC) e períodos de molhamento (6, 12, 24h) na infecção e colonização por esta espécie foram avaliados em frutos de Hass e Fuerte, inoculados com ferimento. Exceto a 10ºC, houve manifestação de sintomas em todas as temperaturas, com maiores lesões e taxas de progresso da doença a 30ºC. Para controle das doenças testou-se tratamento dos frutos por imersão em calda contendo azoxistrobina, cloreto de benzalcônio, dióxido de cloro, Ecolife®, hipoclorito de sódio, imazalil, procloraz e tiabendazol. Dentre esses, procloraz e imazalil foram os mais eficientes. / Brazil is one of the most important avocado producers in the world. However, to compete in the international avocado business it is necessary reduction of post-harvest damages, especially those caused by anthracnose. This work had the following objectives: (i) to identify and to quantify post-harvest damages in Fuerte and Hass avocados; (ii) to identify and to characterize the avocado isolates of Colletotrichum, comparing them with other fruit isolates; (iii) to evaluate the effect of temperature and wetness period in the conidia germination and appressoria formation, as well as in the infection and colonization of Colletotrichum gloeosporioides in avocado; (iv) to evaluate the post-harvest control of anthracnose in avocado using fungicides and sanitizers. Both the anthracnose incidence and other post-harvest damages were evaluated periodically using avocado samples collected at three steps in the packinghouse. It was revealed that anthracnose was the major factor of post-harvest damages, with average incidence of 45.7% in Fuerte and 68.7% in Hass. Identification, characterization and comparative analyses were performed with 93 isolates from avocado, mango, passion fruit and peach according to the colony aspect and growth rate in different temperatures, conidia shape and size, molecular analyses (species-specific PCR and sequencing of ITS and -tubulin genes), pathogenicity and enzymatic activity (amylase, catalase, cellulase, laccase, lipase, pectinase and proteinase). All of the avocado and mango isolates and some isolates from peach and passion fruit were identified as C. gloeosporioides. The species C. acutatum and C. boninense also were indentified in peach and passion fruit, respectively. Phylogenetic analyses performed with some morphological data allowed species differentiation and revealed intra-specific differences between C. gloeosporioies according to the original host. Mango isolates were grouped together into the C. gloesporioides clade. However, independently of the original host, these three Colletotrichum species showed to cross-infect the four evaluated hosts, suggesting lack of pathogenical specificity. There was high variability for all evaluated characteristic. For C. gloeosporioides, spores germination and appressoria formation on the surface of Fuerte avocado incubated under 5, 10, 15, 20, 25, 30, 35 and 40 ºC and wetness periods of 3, 6, 12 and 24 hours showed that this fungus could explore a wide range of temperature. Germination and appressoria formation were observed between 10 and 35 ºC, with optimal temperatures of 23.4 and 24.0 ºC, respectively. Both the germination and appressoria formation were higher with the increase in the wetness period. The effect of temperature (10, 15, 20, 25, 30 ºC) and the wetness period (6, 12, 24h) were evaluated on the infection and colonization of C. gloeosporioides in Fuerte and Hass avocado, which were wound-inoculated. Except at 10 ºC, all tested temperatures led to symptoms expression. The highest disease progress rate and lesion diameter were verified at 30 ºC. Fruit immersion on fungicides solution was tested to control post-harvest diseases using azoxystrobin, benzalkonium chloride, chlorine dioxide, Ecolife, sodium hypochloride, imazalil, procloraz and thiabendazol. Among these fungicides, prochloraz and imazalil were the most efficient in controlling post-harvest diseases in avocado.

Made available in DSpace on 2017-07-21T18:53:11Z (GMT). No. of bitstreams: 1 dissertacao parcial.pdf: 389132 bytes, checksum: 1072407aabab8f91b6ea13999acc01d4 (MD5) Previous issue date: 2009-02-06 / Pectinases, a group of enzymes that degrade pectic substances and break glycosidic linkages, are produced by fungi, yeasts and bacteria, but are also in plants in general and fruit in particular.In the juice industry the pectinolytic enzymes are added to increase the efficiency of the process, decrease the viscosity and reduce the time of filtration. The pectin methylesterase, PME, hydrolyzes the methyl ester groups, forming carboxyl groups in pectin chain, releasing methanol end H3O+. Therefore, its knowledge is vital in order to control the effectiveness of the treatment. The purpose of this study was to determine the optimum conditions of the activity of the pectin methylesterase in industry preparations, proposing a potentiometric procedure for determining the PME activity and compare the data with those obtained by traditional potentiometry and Uv-Vis, evaluate the efficacy of this method in determining the residual activity exogenous of PME in mango juice. The activity of PME in the three commercial samples, Pectinex 100L Plus, Panzym Univers and Panzym Clears, was determined by potentiometry, Uv-Vis spectroscopy, with the bromophenol blue indicator, and the action of alcohol oxidase with acetyl acetone. The reaction consisted of 5.00 mg.mL-1 apple pectin, 0.100 mol.L-1 sodium chloride and 50 μL commercial pectinolytic enzyme for a volume of 30 mL. In all experiments the enzyme deesterification showed first-order kinetics, with increased activity at pH 4.0 to 4.5 and 45 ºC, whereas the complete inactivation occurred at 75 ºC for 10 minutes, in the three industrial preparations. The thermal inactivation of the PME of Pectinex 100L Plus and Panzym Clears preparations occurred under the same conditions, when the activity was measured by the procedures of ΔVNaOH / Δttime or of ΔpH/ Δttime. The activity of PME in industrial preparations at 25 °C and pH 4.5, determined by UV-Vis spectroscopy with bromophenol blue indicator, showed good correlation with the activity determined by the procedures by potentiometry. The stability of the indicator in the pectin solution allows its use to determine the PME activity in samples in which the optimum pH is located in acid band. The release of methanol as measured by alcohol oxidase, followed by the reaction with acetyl acetone to determine the formaldehyde, showed good agreement with the results of the enzyme activity measuring procedures used in this research. The inactivation of residual PME in mango juice occurred at 75 ºC for 20 minutes of exposure in the procedure ΔVNaOH / Δttime and 10 minutes of exposure during the procedure ΔpH/ Δttime. The residual activity of PME in 70 °C for 10, 20 and 30 minutes of exposure in the presence of juice was higher than in the control, indicating its protective effect. The procedure of ΔpH/ Δttime shows good correlation with other methods, with the advantage of precise and direct measures of [H+], excusing a series of reagents and high costs materials. / As pectinases, um grupo de enzimas que degradam substâncias pécticas e rompem ligações glicosídicas, são produzidas por fungos filamentosos, leveduras e bactérias, mas encontram-se também em plantas em geral e em frutas, em particular. Na indústria de sucos as enzimas pectinolíticas são adicionadas para aumentar o rendimento do processo, diminuir a viscosidade e reduzir o tempo de filtração. A pectina metilesterase, PME, hidrolisa os grupos metil éster, formando grupos carboxilícos na cadeia da pectina, produzindo metanol e H3O+.Portanto, é fundamental o seu conhecimento, a fim de controlar a eficiência do tratamento. O objetivo deste trabalho foi determinar as condições ótimas da atividade da PME presente em preparações industriais, propor um procedimento potenciométrico para determinação da atividade da enzima e comparar os dados com os obtidos por potenciometria tradicional e Uv- Vis, avaliar a eficiência do método proposto na determinação da atividade residual da PME exógena no suco de manga. A atividade da PME nas três amostras comerciais, Pectinex 100L Plus, Panzym Univers e Panzym Clears, foi determinada por potenciometria, espectroscopia Uv-Vis, com o indicador azul de bromofenol, e pela ação do álcool oxidase com acetil acetona. A reação consistiu de 5,00 mg.mL-1 de pectina de maçã, 0,100 mol.L-1 de cloreto de sódio e 50 μL de enzima pectinolítica comercial para um volume de 30 mL. Em todos os experimentos a desmetoxilação enzimática mostrou uma cinética de primeira ordem, com maior atividade em pH 4,0 a 4,5 e 45 ºC, sendo que a inativação completa ocorreu a 75 ºC por 10 min, nas três preparações industriais. A inativação térmica da PME das preparações Pectinex 100L Plus e da Panzym Clears ocorreu sob mesmas condições, quando a atividade foi medida pelos procedimenos de ΔVNaOH / Δttempo ou de ΔpH/ Δttempo. A atividade da PME nas preparações industriais a 25 ºC e pH 4,5, determinada por espectroscopia Uv-Vis com o indicador azul de bromofenol, apresentou boa correlação com a atividade determinada pelos procedimentos por potenciometria. A estabilidade do indicador em solução com a pectina permite a sua utilização para determinar a atividade da PME em amostras nas quais o pH ótimo localiza-se na faixa ácida. A liberação do metanol medida pela álcool oxidase, seguida da reação com a acetil acetona para determinar o formaldeído, mostrou boa concordância com os resultados dos procedimentos de medida de atividade enzimática utilizados neste trabalho. A inativação da PME residual em suco de manga ocorreu na temperatura de 75 ºC por 20 min de exposição no procedimento ΔVNaOH / Δttempo e durante 10 min de exposição pelo procedimento ΔpH/ Δttempo. A atividade residual da PME a 70 ºC por 10, 20 e 30 min de exposição em presença do suco foi maior do que no controle, indicando o seu efeito protetor. O procedimento da ΔpH/ Δttempo apresenta boa correlação com os demais métodos, com a vantagem de medidas precisas e diretas da [H+], dispensando uma série de reagentes e materiais de custos elevados.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-16T14:45:19Z No. of bitstreams: 1 Alice Maria Goncalves Santos.pdf: 828943 bytes, checksum: e2e058b935319e6ca5c5d01db52c323c (MD5) / Made available in DSpace on 2017-02-16T14:45:19Z (GMT). No. of bitstreams: 1 Alice Maria Goncalves Santos.pdf: 828943 bytes, checksum: e2e058b935319e6ca5c5d01db52c323c (MD5) Previous issue date: 2009-02-25 / In postharvest, the mango is predisposed to several diseases, including the complex known as stem-end rot fungus that has Lasiodiplodia theobromae as a major player in addition to rot by fusicocco (Fusicoccum parvum) and anthracnose caused by Colletotrichum gloeosporioides. The mangicultura is of great economic importance for Brazil, but has been losing ground with the losses that occur in post-harvest disease incidence mainly during transportation and storage, there is need to develop technologies that demonstrate effectiveness in delaying the senescence of fruits improving the marketing capability. Among the technologies we highlight the physical methods such as the use of gamma irradiation, cold storage and use of modified atmosphere. This study aimed to evaluate the three methods of physical control over the development of post-harvest mango and on the physico-chemical properties held for the treatments. For this, the fruit were inoculated with different firopatógenos and after 24 hours applied to gamma radiation doses of 0, 0.25, 0.35, 0.45 kGy, and as the Cobalt 60 source. The fruits were packed with PVC film with 380 mm x 10 microns in trays and kept under refrigeration at 13 º C for 15 days and after that period kept at room temperature, 25 ° C without the plastic film. We observed a reduction of disease development for the three fungi studied, reaching the full control of the disease when evaluating the development of anthracnose in mangoes that were subjected to higher dose of 0.45 kGy. Mangoes irradiated showed no significant differences for some parameters (ascorbic acid, total acidity (TTA), pH, total soluble solids (TSS), ratio (TSS / TTA), firmness and flesh color). Inoculated mangoes like C. gloeosporioides showed no significant changes to the physical and chemical properties, except for spots on the peel. The mangoes inoculated with L. theobromae and F. parvum showed no significant differences between the treatments that compromise the marketing thereof, thus demonstrating the efficiency of these technologies in disease control and not causing changes in properties of the sleeves / Na pós-colheita, a manga está predisposta a diversas doenças, entre elas o complexo conhecido como podridão peduncular que tem o fungo Lasiodiplodia theobromae como um dos principais agentes, além da podridão por fusicoccum (Fusicoccum parvum) e a antracnose causada por Colletotrichum gloeosporioides. A mangicultura é de grande importância econômica para o Brasil, mas vem perdendo espaço com as perdas que acontecem na pós-colheita, principalmente pela incidência de doenças durante o transporte e armazenamento, havendo necessidade de desenvolver tecnologias que demonstrem eficiência em retardar a senescência das frutas, melhorando a capacidade de comercialização. Entre as tecnologias destacam-se os métodos físicos como a utilização da radiação gama, o armazenamento refrigerado e o uso da atmosfera modificada. O presente trabalho objetivou avaliar os três métodos de controle físico sobre o desenvolvimento pós-colheita de manga e sobre as características físico-químicas conservadas durante os tratamentos. Para isso, as frutas foram inoculadas com os diferentes firopatógenos, e após 24 horas aplicada a radiação gama nas doses de 0; 0,25; 0,35; 0,45 kGy, tendo como fonte o Cobalto60. As frutas foram embaladas com filme plástico de PVC com 380 mm x 10 microns em bandejas de isopor e mantidas sob refrigeração a 13ºC por 15 dias e após esse período conservadas sob temperatura ambiente, de 25ºC sem o filme plástico. Foi observada uma redução do desenvolvimento da doença para os três fungos avaliados, chegando ao controle total da doença quando avaliado o desenvolvimento da antracnose nas mangas que foram submetidas à dose mais alta de 0,45 kGy. As mangas irradiadas não demonstraram diferenças significativas para alguns dos parâmetros avaliados (ácido ascórbico, acidez titulável total (ATT), pH, sólidos solúveis totais (SST), razão (STT/ATT), firmeza e cor da polpa). As mangas inoculadas como o C. gloeosporioides não apresentaram alterações significativas para as propriedades físico-químicas, exceto manchas nas cascas. As mangas inoculadas com L. theobromae e F. parvum não apresentaram diferenças significativas entre ao tratamentos aplicados que comprometesse a comercialização das mesmas, demonstrando assim a eficiência dessas tecnologias no controle das doenças e não causando alterações das propriedades das mangas.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Foram realizados cinco experimentos objetivando determinar o consumo e digestibilidade, desempenho e caracterÃsticas quantitativas da carcaÃa de ovinos alimentados com dietas contendo subprodutos, com base na matÃria natural, (SPU), da banana (Musa sp.) desidratada (SPB), da manga (Mangifera indica) desidratada (SPM) e do urucum (Bixa orellana L.). No primeiro, segundo e terceiro experimentos foram avaliados os teores de matÃria seca (MS), matÃria orgÃnica (MO), proteÃna bruta (PB), fibra em detergente neutro (FDN), fibra em detergente Ãcido (FDA), hemicelulose (HCEL), lignina (LIG), nitrogÃnio insolÃvel em detergente neutro (NIDN), nitrogÃnio insolÃvel em detergente Ãcido (NIDA), carboidratos totais (CT), carboidratos nÃo fibrosos (CNF), os nutrientes digestÃveis totais (NDT) e fator de efetividade fÃsica da FDN. Ainda foram avaliados o consumo voluntÃrio, digestibilidade aparente da MS, PB, FDN, FDA, CHOT, CNF, NDT e balanÃo de nitrogÃnio (BN). No quarto e quinto experimentos foram avaliados os consumos de nutrientes em g/dia, % PV e g/kg0,75, ganho em peso e conversÃo alimentar. Como tambÃm foram avaliadas caracterÃsticas quantitativas da carcaÃa e anÃlise sensorial de dietas com adiÃÃo de 20% do SPB, com 30% do SPM e 40% do SPU. No primeiro experimento, a adiÃÃo do subproduto de banana (SPB) nÃo influenciou (P>0,05) o consumo de matÃria seca (MS) e matÃria orgÃnica (MO) quando expressos nas diferentes formas, obtendo-se valores mÃdios de 677,3 e 605,81 em g/dia, respectivamente. A adiÃÃo do SPB promoveu um aumento significativo (P<0,05) no CPB e CEE de 34,3 a 46,5 e de 10,63 a 59,9 g/dia e reduÃÃo de 3,07 unidades percentuais para o consumo de FDN. Com relaÃÃo aos coeficientes de digestibilidade da MS, PB, MO, EE, FDA e CHOT observou-se efeito negativo, excetuando, o CDFDN que nÃo foi influenciado (P>0,05) com adiÃÃo do SPB em substituiÃÃo ao feno. No segundo experimento, os consumos em g/dia de MS, MO, PB, EE, FDN e FDA apresentaram resposta quadrÃtica estimando-se consumos mÃximos de matÃria seca e matÃria orgÃnica de 36,11 e 37,8%, respectivamente, com a adiÃÃo do SPM. Contudo, nÃo houve diferenÃa (P>0,05) para a digestibilidade aparente dos nutrientes. Entretanto, a digestibilidade aparente da proteÃna bruta (CDPB) e o balanÃo de nitrogÃnio apresentaram comportamento quadrÃtico. No terceiro experimento, houve aumento nos consumos e dos nutrientes com adiÃÃo do subproduto do urucum (SPU), excetuando-se o consumo de EE que nÃo houve efeito (P>0,05). O comportamento linear positivo foi verificado para os coeficientes de digestibilidade (CD) da MS, MO e PB, jà para os CDEE, CDFDN, CDFDA e CDCHOT nÃo houve efeito (P>0,05) significativo. A adiÃÃo do SPU promoveu um balanÃo de N positivo. No quarto experimento, nÃo foram observadas diferenÃas significativas (P>0,05) entre os tratamentos para os consumos de matÃria seca em g/animal/dia. PorÃm, observou-se aumento para os consumos em %PV e g/kg0,75, para a dieta com adiÃÃo do SPU. Em relaÃÃo aos consumos de PB o SPB e SPM, apresentaram superioridade em relaÃÃo aos ovinos que receberam a dieta SPU. Para os CFDN nÃo foram observadas diferenÃas (P>0,05) entre as dietas nas diversas formas que foram expressas. O mesmo comportamento foi verificado com relaÃÃo ao ganho em peso, pesos de carcaÃa quente e fria e os respectivos rendimentos de carcaÃa quente e fria. Observaram-se valores mÃdios de RCQ e RCF respectivos de 46,05; 46,38; 46,54; 48,39% e 42,27; 45,67; 45,79; 47,72% para as dietas padrÃo (DP), SPB, SPM e SPU. Com relaÃÃo aos cortes comercias, houve efeito significativo (P<0,05) apenas para o lombo anterior em kg e para a paleta em % do PCF. Para a Ãrea de olho de lombo foram registrados valores respectivos de 8,28; 9,61; 1,38 e 10,82 para as dietas DP; SPB; SPM e SPU. No quinto experimento, relativo à dissecaÃÃo da perna dos ovinos, nÃo foi verificado efeito significativo (P>0,05) para a relaÃÃo M/O; M/G e para o Ãndice de musculosidade da perna (IM). Obtiveram-se valores para o IM de 0,79; 0,73; 0,81 e 0,82, respectivamente, para a DP; SPB; SPM e SPU. No sexto experimento, os atributos sensoriais da carne de ovinos apresentaram superioridade para o grau de dureza da carne dos ovinos alimentados com SPM e SPU. Menores suculÃncia e sabor ovino foram verificados, respectivamente, nas dietas SPM e SPB / Five experiments was conducted with the objective of evaluating the consume and digestibility, performance and quantitative characteristics of the lambs carcass fed with diets containing by - products, with base in the natural matter of the banana ( Musa sp .), ( BBP) , of the mango ( Mangifera ind ica ) ( MBP) , of the annato ( Bixa orellana ) ( ABP) . i n the first, second and third experiments were determination of dry matter ( DM), organic matter (OM), crude protein (CP), neutral detergent fiber ( NDF ), acid detergent fiber (ADF), hemicellulose (HCEL), lig nin (LIG), neutral detergent insoluble nitrogen (NIDN), acid detergent insoluble nitrogen (ADIN) , total carbohydrates (TC) , non - fibrous carbohydrates (NFC), total digestible nutrients (TDN) , and factor of physical effectiveness of FND. They were still eval uated the voluntary intake and coefficients of digestibility of DM, CP, NDF, ADF, CHOT, TDN, and nitrogen balance (NB). In the fourth and fifth experiments were evaluated the nutrients intake in g/day , % BW and g/kg 0,75 daily gain and alimentary conversion . As well as they were evaluated quantitative characteristic of the carcass and sensorial analysis of diets with addition 20% of BBP with 30% of MBP and 40% of ABP . In the first experiment the addition of the banana's by - product (BBP) it didn't influence ( P>0.05) the dry matter intake (DMI), and organic matter (OMI ) intake when expressed in the different forms with values of 677.3 and 605. 81 in g/day , respectively observed . The (BBP) addition increased (P <0. 05) in crude protein intake (CPI) and ether extrac t (EEI) intak e from 34.3 to 46.5 and from 10. 63 to 59 . 9 g/day and reduction of 3 . 07 percentage units for the NDF intake. Regarding the of digestibility coefficients of DM, CP DO, EE, ADF and TC was observed negative effect (P<0. 05) , excepting, CDNDF that i t was not influenced (P>0.05) with addition of BBP . In second experiment the day of DM, DO, CP, EE, NDF, ADF intakes g/day presented quadratic answer being considered maximum dry matter and organic matter intake 36. 11 and 37. 8% , re spectively of addition of mango by - product (MBP). However there was not difference (P >0.05) for the apparent digestibility of the nutrients, except the apparent digestibility of the crude protein (DCCP) the addition of (MBP) quadratic behavior observed. In third experiment annatto by product (ABP) addition increased (P <0.05) in nutrients intake , excepted the EE intake was not effect significant (P>0. 05) the addition anatto by product (ABP ) with values in the 11.5 and 0. 05 g/day e % BW . The linear ly behavior was verified for the di gestibility coefficients (DC) of DM , DO and CP, already for CDEE, CNDF, CDANF XIX and CDCHOT didn't have effect (P>0. 05). The anatto by - product (ABP ) addition promoted a positive balance of N . In the fourth experiment significant differences were not observed (P>0.05) among the treatments for the dry matter intake in g/ day . However, increase was observed for the % PV and g/kg 0.75 intake for the diet with addition of annato by - product, banana by - product and mango by product . The intake of CP by - product of mango and banana &#769;s by - product (BBP) presented superiority in relation to the lambs that received the other diets. For the EE intake BBP it was observed higher values the other diets and NDF intake it was not observed differences (P>0.05) among the diets in the s everal forms that were expressed . The same behavior was verified regarding the weight gain , hot carcass weight (HCW) and cold carcass (CC W ) and the respective yield of hot and cold carcass. The values of hot carcass yield and cold carcass (CC) were 46.05; 46.38; 46.54; 48. 39% and 42 . 27; 45.67; 45.79; 47. 72% for the diets (PD), BBP, MBP a nd ABP respectively . In respect to the cuts trade there was effect significant (P <0 . 05) just for the anterior loin in kg and for the shoulder % WCC . For loin eye area (LEA ) were registered respective values of 8.28; 9.61; 1. 38 ; 10. 82 for the diets PD; BBP; MBP; ABP. In the fifth experiment with the dissection of the leg of the lambs significant effect was not verified (P>0 . 05) for the accounting M/O; M/G and for the index of muscularity of the leg (MI ) that obtained values of 0.79; 0.73; 0.81; 0. 82 for PD; BBP; MBP; MBP in the sixth experiment the attributes sensorial of the lambs meat presented superiority for the degree of hardness of the meat of the lambs fed with MBP and MBP. To smallest succulency and the smallest flavor lambs they were verified in the diets MBP and BBP respectively.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2015-09-14T22:46:49Z No. of bitstreams: 1 disserta??o Nara Munick Cerquira Lopes Oliv eira.pdf: 4232139 bytes, checksum: a9ff1ac54121065ff87576be3e6c69b1 (MD5) / Made available in DSpace on 2015-09-14T22:46:49Z (GMT). No. of bitstreams: 1 disserta??o Nara Munick Cerquira Lopes Oliv eira.pdf: 4232139 bytes, checksum: a9ff1ac54121065ff87576be3e6c69b1 (MD5) Previous issue date: 2013-10-04 / In an attempt to pathogen reduction in sewage sludge there are several post treatments alternatives, such as thermal drying, lime stabilization, composting and others. The present study aimed to evaluate an alternative process to reduce pathogens in sewage sludge by using mango processing waste, which contains antimicrobial properties against gram-positive and negative bacteria. The sewage sludge from UASB reactor was stabilized for 30 days in drying bed and submitted to the sanitization process with different concentrations of mango?s peel (5, 10, 15, 20 and 30% (w/w)) and kernel seed (5, 10, 15, 20 and 30% (w/w)), with sewage sludge as a positive control and alkalinized sludge as negative control. It was monitored total and fecal coliforms, Salmonella spp., Enterococcus spp. and Escherichia coli concentrations over 90 days (at 0, 3, 7, 10, 15, 20, 30, 45, 60 and 90 days), as well as determination of total and volatile solids, moisture, total organic carbon, nitrogen, pH, phosphorus and viable helminthes eggs. The results indicated that the concentrations of carbon, nitrogen and phosphorus of treatments showed little variation during the trial period. At day 90, the levels of total and fecal coliforms were <3 MPN/g TS in positive and negative controls as well as in most of treatments with mango?s residues. The use of mango?s kernel seed or peel resulted in a reduction of 99.9999% of enterococci, 99.999% of E. coli and 99% of salmonella numbers present at the beginning of this evaluation. Although there has been a reduction in the levels of pathogens, the biosolids obtained still has restrictions for agricultural use, according to current Brazilian legislation: CONAMA Resolution 375/06 and Normative Instruction N0 64/2008 of the Ministry of Agriculture. / Na tentativa de redu??o de pat?genos no lodo de esgoto existem varias alternativas de p?s-tratamentos tais como: secagem t?rmica, estabiliza??o com cal, compostagem entre outros. O presente estudo teve como objetivo avaliar um processo alternativo de redu??o de pat?genos no lodo de esgoto pelo uso de res?duos do processamento da manga, que contem propriedades antimicrobianas contra bact?rias gram-positivas e negativas. O lodo de esgoto proveniente do reator UASB foi estabilizado por 30 dias em leito de secagem e submetido ao processo de higieniza??o com diferentes concentra??es de casca (5, 10, 15, 20 e 30% (p/p)) e de semente (5, 10, 15, 20 e 30% (p/p)) de manga, utilizando como controle positivo o lodo seco e controle negativo o lodo seco alcalinizado. Foram monitoradas as concentra??es de coliformes totais e termotolerantes, Salmonella spp. Enterococus spp. e Escherichia coli ao longo de 90 dias (nos tempos 0, 3, 7, 10, 15, 20, 30, 45, 60 e 90 dias), bem como a determina??o de s?lidos totais, s?lidos vol?teis, umidade, carbono org?nico total, nitrog?nio, pH, fosforo e ovos vi?veis de helmintos. Os resultados indicaram que as concentra??es de carbono, nitrog?nio e f?sforo dos tratamentos analisados apresentaram pouca varia??o durante o per?odo de avalia??o. Ao final dos 90 dias, os n?veis de coliformes totais e termotolerantes foram <3 NMP/g ST no controle positivo e negativo, bem como na maioria dos tratamentos com res?duos de manga. A utiliza??o de casca ou semente de manga resultou na redu??o de 99,9999% dos Enterococos, 99,999% de E. coli e 99% da salmonela presente no in?cio da avalia??o. Embora tenha havido redu??o nos n?veis de pat?genos, o bioss?lido obtido ainda apresenta restri??es de uso agr?cola, de acordo com as legisla??es brasileiras vigentes: Resolu??o CONAMA 375/06 e Instru??o normativa N0 64/2008 do Minist?rio da Agricultura.

The South African fresh fruit industry is a significant exporter, accounting for approximately 45% of the country’s agricultural exports. Of the total exported fruit in the 2005/06 season, 60% was subtropical fruit. However, certain physiological rind disorders such as mango lenticel damage and citrus rind pitting are frequently observed, reducing the commercial value of the fruit. This thesis deals with the epidemiology of these rind physiological disorders, in an attempt to obtain basic information that could serve as a guideline to predict and manage the fruit susceptibility to these disorders. The study further investigated the relative effects that certain pre-harvest factors have on the postharvest development of these disorders. Factors of particular interest were harvest maturity, climate and the mineral content of the fruit. Rind pitting is a physiological disorder of citrus that develops during storage. A study was conducted to investigate the relative effects that certain pre-harvest factors have on the post-harvest development of superficial rind pitting in ‘Benny Valencia’ oranges. Factors of particular interest were harvest maturity, climate and the mineral content of the fruit. In addition, trees were treated with two different formulations of nitrogen viz. limestone ammonium nitrate (LAN) and a slow release nitrogen fertilizer (Horticote®), during March 2006. The fruit were then sampled on a two-weekly basis over a period of three months. On each sampling date a set of quality related readings, such as juice sugar and titratable acid concentration were taken, after which the mineral concentration of the exocarp and mesocarp was measured. Fruit were also stored under export simulation conditions. The results indicate that fruit from trees that received additional N were more susceptible to rind pitting than those from control trees. Of the two N applications, fruit from trees that received slow release N were more susceptible to rind pitting than fruit from trees that received the LAN treatment. Another important observation made was that the nitrogen concentration of oranges from trees that received extra nitrogen fertilizer was lower than that from the controls. In addition, experimental fruit were smaller than control fruit. Fruit from trees that received the slow release nitrogen treatment were smallest. A sink/source hypothesis aimed at explaining this phenomenon has been formulated and is currently being investigated. A number of control mechanisms are also being explored. Mango lenticel damage is a serious defect that occurs on the rind of the fruit. This condition causes fruit to attain a speckled appearance and become unattractive to the buyer. Each season, the disorder reduces the packout of fresh fruit by about 16%. Several preharvest factors play a critical role in the postharvest development of lenticel damage. Preliminary studies have shown that the incidence of lenticel damage has some relationship to fruit moisture and fruit nutrient concentration, depending on which of these factors first achieve a critical threshold. A study was conducted to develop appropriate skin moisture content parameters to predict lenticel damage potential before harvest. The study further aimed to provide certain biological markers regarding appropriate nitrogen fertilization practices to reduce lenticel damage. To do this, two trials were conducted approximately a month before harvest. Firstly, a plastic ground cover to restrict water supply was laid under ‘Tommy Atkins’ trees at Numbi Estates in the Hazyview area of the Mpumalanga province, South Africa. Secondly, additional nitrogen was applied as three different formulations, viz. limestone ammonium nitrate (LAN), potassium nitrate (KNO3), and a slow release nitrogen fertilizer under trade name Horticote®, to two ‘Tommy Atkins’ and two ‘Keitt’ orchards at Bavaria Estates in the Hoedspruit area of the Limpopo province, South Africa. Fruit samples were harvested, packed and stored at different intervals after rain during January 2006. With regard to lenticel damage on ’Tommy Atkins’ fruit from Numbi, there was no significant difference between the control and plastic cover treatments. However, when compared to fruit from other localities, the Numbi fruit had the highest incidence of lenticel damage, followed by the conventional orchard at Bavaria. The Numbi fruit, which had the highest incidence of lenticel damage, also had the highest pulp and skin nitrogen concentration. Of the four treatments at Bavaria, the LAN treatment had the highest incidence of lenticel damage, but the pulp and skin nitrogen concentrations of this treatment were comparable with the other treatments. The organic fruit had significantly lower lenticel damage incidence and also had the lowest pulp and rind nitrogen concentrations. Similarly, ‘Keitt’ results showed that the intensity of lenticel damage was significantly higher in the orchard that received additional nitrogen in the form of LAN. From the results it was, however, not possible to formulate nitrogen-lenticel damage correlations. The study failed to prove the case for a direct relationship between the disorder and with nitrogen, as there were no significant or consistent correlations with nitrogen content. An interesting relationship was nevertheless observed between lenticel damage and the time of harvest before and after rainfall. The results indicated that both ‘Tommy Atkins’ and ‘Keitt’ fruit become more susceptible to lenticel damage when harvested a day after rainfall and this gradually reduces afterwards. The effect of rainfall in this regard and a sink-source hypothesis arising from these observations are also discussed. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

Made available in DSpace on 2016-08-12T19:15:31Z (GMT). No. of bitstreams: 1 WignaGNS_DISSERT.pdf: 513215 bytes, checksum: 78dc5f47f01abd85a7757079de7ad67a (MD5) Previous issue date: 2015-02-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Brazil is one of the largest fruit producers in the world, however part of its production is not exported due to phytosanitary barriers imposed by importing countries. The incidence of frugivorous flies in orchards cause depreciation in fruits and serious damage to the producer, an alternative for the control of these pests, are parasitoids. The objective of this study was know to frugivorous flies and their parasitoids, associated with mango fruits in two maturity stages and the fruit of ripe guava. Mango fruits were harvested at physiological maturity stage and mature on the plant, and fruit ripe guava in the states of Rio Grande do Norte (Polo Açu-Mossoró) and Ceará. After harvest, the fruits were taken to the of laboratory of applied entomology of UFERSA, where they were weighed and placed in plastic containers containing vermiculite and closed with voile fabric. After 10 to 15 days vermiculite was sieved and pupae obtained counted and placed in Petri dishes until the emergence of adults. Also were placed traps types of McPhail and Jackson, containing hydrolyzed corn protein 5% and Trimedilure, respectively, in four orchards with products intended to export. Weekly (McPhail) and fortnightly (Jackson), the traps were monitored and insects captured sent to the laboratory. We collected 400 mango fruits and 1.331 guava fruits. The mango fruits in physiological maturity stage were not infested by any insect, since the ripe fruit on the plant were infested by C. capitata (34.4%) and Z. indianus (65.6%), the guava fruits were obtained only pupae of Z. indianus. Besides the flies were found collected figitídeos parasitoids of Z. indianus. Only, C. capitata was captured in traps and contacted that non infestation of the fruits in physiological maturity stage, for this tefritídeo is not associated with its population density in the orchard, but the inherent fruit factors / O Brasil é um dos maiores produtores de frutas do mundo, no entanto a incidência de dípteros frugívoros nos pomares causa sérios prejuízos a produção, devido ao fato de suas larvas alimentarem-se dos frutos tornando-os impróprios para o consumo in natura, além de algumas espécies, como as moscas-das-frutas, limitarem a exportação da produção. O controle desses dípteros é realizado basicamente utilizando produtos químicos, porém devido as exigências do mercado consumidor, métodos alternativos de controle estão sendo cada vez mais utilizados, como por exemplo, os parasitoides. Este trabalho teve como objetivos: a) Conhecer os dípteros frugívoros associados a frutos de manga e qual estádio de maturação (maturação fisiológica ou maduro na planta) é mais suscetível a infestação pelos dípteros frugívoros, em pomares comerciais localizados no Polo Açu-Mossoró (RN) e b) relatar a ocorrência de figitídeos parasitoides de drosofilídeos em frutos maduros de manga e goiaba, nos estados do Rio Grande do Norte e Ceará, respectivamente. Os frutos coletados eram encaminhados ao laboratório de Entomologia Aplicada da UFERSA, onde eram pesados, acondicionados em recipientes plásticos contendo vermiculita e fechados com tecido voile. Decorridos 10 a 15 dias a vermiculita era peneirada e os pupários obtidos contados e colocados em placas de Petri até a emergência dos adultos. Os frutos de manga no estádio de maturação fisiológica não estavam infestados por diptero, já os frutos de manga maduros estavam infestados por C. capitata (34,4%) e Z. indianus (65,6%). Verificou-se também que a não infestação de C. capitata nos frutos de manga no estádio de maturação fisiológica está relacionado com as características dos frutos e não a densidade populacional da praga no campo. Associados aos frutos maduros de manga e goiaba foram encontrados exemplares de Dicerataspis grenadensis e Leptopilina boulardi, respectivamente, e este é o primeiro relato de D. grenadensis no estado do Rio Grande do Norte e de L. boulardi no Ceará