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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Non-invasive quality evaluation of fruits and vegetables using ultrasound

Cheng, Yanling 10 October 2005 (has links)
Ultrasonic techniques were investigated for non-invasive quality evaluation of selected fruits and vegetables. An ultrasonic non-destructive evaluation system was developed and used to investigate physical and acoustical property changes for the selected fruits and vegetables non-invasively. The system included a high power burst pulser, a broadband receiver, a digital storage oscilloscope, two pairs of transducers of 250 kHz and 1 MHz, and a microcomputer system, which was interfaced with the ultrasonic equipment through a General Purpose Interface Board (GPIB), for data acquisition and analysis. Using potatoes and apples, several forms of the acoustic indices were investigated using the system. Investigation of “Yukon-Gold’ potatoes concentrated on the physical and acoustical property changes during the storage period of approximately five months. The tests were conducted at regular intervals. Ultrasonic velocity, attenuation coefficient, modulus of elasticity, and tissue density were determined for each potato along two different orientations — longitudinal and transverse. Three varieties of apples, ‘Golden Delicious’, ‘Red Delicious’, and ‘Granny Smith’, were tested to detect their physiological changes with ripeness. The tests were conducted at two different stages of ripeness. In each test, ultrasonic velocity, attenuation coefficient, modulus of elasticity, and tissue density were determined along longitudinal and radial directions of the apples. Frequency analysis of the transmitted ultrasonic signals through potato and apple samples was also conducted using Fast Fourier Transform (FFT) techniques. The experimental results for the potatoes and apples indicated the measured acoustical and physical properties differed along different orientations; i.e., potato and apple tissues are anisotropic materials. Apple tissues transmitted much lower frequency components than potato tissues and the transmitted frequency range was much narrower due to the much higher percentage of intercellular void space in apple tissues (24%) than in potato tissues (2%). The ultrasonic measurements were able to detect physiological changes and physical heterogeneities in fruit and vegetable tissues. Therefore, the ultrasonic technique can be a useful and quick method for evaluating firmness as well as textural and rheological property changes during storage of fruits and vegetables. Hollow hearts in ‘Atlantic’ potatoes were successfully detected using the ultrasonic nondestructive evaluation system at 250 kHz. A objective this work was to develop a quantitative, non-invasive method for hollow heart detection in potatoes, and to provide information for designing evaluation equipment which could serve as an automatic quality control step in the production process. The analysis of the transmitted ultrasonic signals through the potatoes was carried out in both time and frequency domains. The results of the investigation of ‘Atlantic’ potatoes showed that the waveform of transmitted ultrasonic signals through a hollow heart potato differed significantly from that of a normal potato. Further, the defective potatoes could be separated on the basis of the amount of ultrasonic power transmitted through a potato. By means of digital Fourier analysis, the 0<sup>th</sup> spectral moment, M₀, was determined from the power spectral density curve of a transmitted ultrasonic signal. The spectral moment represents the amount of ultrasonic power transmitted through a tested potato, and was chosen as the basis for quantitative, non-invasive method for hollow heart detection, since power transmission of ultrasonic wave was affected by the presence of hollow heart in potatoes. Potatoes with hollow heart transmitted much less ultrasonic power than normal potatoes — approximately 89% less on average. There was a distinct separation between the normal potatoes and hollow heart potatoes. The reliability of this method was confirmed. Among 41 ‘Atlantic’ potatoes tested, all 26 hollow-heart potatoes were identified without exception. Therefore, the parameter M₀ could provide an effective method of analyzing the ultrasonic measurements for quantitative, non-invasive evaluation of hollow hearts in potatoes. This non-invasive method could be used to identify internal quality of potatoes that is difficult to evaluate from external appearance. Such a measurement offers promises for the development of equipment that would sort potatoes with hollow heart automatically. / Ph. D.
22

Influence of bagging materials on maturity indices and post-harvest quality of 'roma vf' and 'tinker' cherry tomatoes

Mafotja, Mokgadi Pollet January 2022 (has links)
Thesis (M.Sc. (Horticulture)) -- University of Limpopo, 2022 / The purpose of this study was to assess the impact of pre-harvest bagging materials on maturity indices and post-harvest quality of cherry tomatoes. At pre-harvest, fruit were bagged with blue and transparent plastic bags of 0.075- and 0.025-mm thickness, respectively. The non-bagged fruit were considered as control treatment. The experiment was carried out in a randomized complete block design arranged in a 2 × 3 factorial arrangement with three replications. Physical quality parameters such as; colour changes (L*, a*, b*, C*, h˚, and ΔE), firmness, weight loss and size were assessed. Physico-chemical parameters such as pH, total soluble solids, and total titratable acidity were also evaluated. Bagging had a significant effect on the quality of both cherry tomato cultivars. The results showed that bagging cherry tomatoes at 1.5 cm diameter with blue and transparent plastic bags accelerated maturity. Moreover, bagging with transparent plastic bags enhanced exocarp colour, reduced weight loss, retained larger size, increased pH and TTA, with an increase in TSS when compared with blue plastic bags and control, respectively at 12 days of shelf-life. In conclusion, the findings demonstrate that pre-harvest bagging has the potential to improve maturity indices and post-harvest quality of cherry tomatoes. Therefore, pre-harvest bagging can be used as an alternative method to enhance cherry tomato fruit quality and shelf-life. / NRF
23

Non-destructive measurement of internal fruit quality using SQUID-NMR techniques

Nturambirwe, Jean Frederic Isingizwe 12 1900 (has links)
Thesis(MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The SQUID-NMR technique has been increasingly recommended by many researchers as holding a lot of potential, and it is believed it will become an invaluable tool for non-destructive evaluation in the future. Most of its potential is yet to be exploited. Non-destructive quality control of food products is one of the applications where such a system is being tried. Much of the progress that has been made in improving such a system to the present degree of user friendliness and cost effectiveness shows that, with more effort, it would be possible to implement the technology for on-line sorting, and possibly to reduce it down to hand-held devices. The goal was to investigate the feasibility of the internal fruit quality measurements using the NMR technique, and to develop a SQUID system suitable for SQUID-NMR application, intended for a later integration in a full SQUID-NMR system. A working dc SQUID was manufactured on an YBCO (Y Ba2Cu3O7􀀀 ) thin film deposited on a 10 mm x 10 mm MgO substrate. The SQUID was made of microbridge Josephson junctions, patterned by using the double resist laser lithography method, implemented during the course of this manufacturing process. The test of the SQUID showed a non-hysteretic current-voltage characteristic. Under the action of bringing a magnet closer to the SQUID under test, and then retracting it, the modulation of the I-V curve was observed. The critical current of the SQUID was 20 A and the resistance was 5.5 A series of experiments were performed on destructive measurements of the sugar content in table grapes using NMR, in order to evaluate the feasibility of this technique. The total sugars(TSS) measurements of the same samples were carried out by refractometry, chosen as a conventional method for validation. The NMR measurements were evaluated to be 5.4% precise and have an accuracy of 9.3% relative to the refractometry measurements. A further series of experiments were carried out on a high-Tc SQUID-NMR system. A high correlation coefficient (0.85) of the increasing values of the T1 and T2 relaxation times to the decreasing concentration of sugar (sucrose) in water was obtained. Non-destructive measurements T1 and T2 in table grapes suggested a possible prediction of sugar content in table grapes from the values of T1 or T2. This technique also presented many advantages compared to the conventional high field NMR technique, such as the fast measurements that do not require spectral processing, the ease of sample preparation, and its non-destructive nature. / AFRIKAANSE OPSOMMING: Die SQUID-NMR tegniek word al hoe meer aanbeveel deur navorsers oor die groot potensiaal, en dit beloof om in die toekoms van onskatbare waarde te wees in nie vernietigende evaluering. Die potensiaal moet grotendeels nog ontgin word, en die nie vernietigende kwaliteitsbeheer van voedselprodukte is een van die toepassings wat hier getoets word. Die vooruitgang tot dusver om die stelsel te verbeter wat die gebruikersvriendelikheid en koste-effektiwiteit betref, toon dat met effens meer moeite dit moontlik sal wees om die tegnologie aan te pas vir lynsortering van vrugte, en om dit dalk ook as handtoestel beskikbaar te stel. Die vooruitgang tot dusver om die stelsel te verbeter wat die gebruikersvriendelikheid en koste-effektiwiteit betref, toon dat met effens meer moeite dit moontlik sal wees om die tegnologie aan te pas vir lynsortering van vrugte, en om dit dalk ook as handtoestel beskikbaar te stel. Die doel is om die uitvoerbaarheid van interne vrugtekwaliteit metings deur hierdie tegniek te ondersoek en om ’n SQUID stelsel te ontwikkel wat gepas is vir SQUIDNMR toepassing, met die doel om dit later in ’n volledige SQUID-NMR stelsel te kan integreer. ’n Werkende GS-SQUID is vervaardig op ’n YBCO dunfilm wat op ’n 10 mm x 10 mm MgO substraat gedeponeer is. Die SQUID is van mikro-brug Josephson aansluitings/ voegvlakke, waarop in die loop van die vervaardigingsproses ’n patroon m et dubbelweerstand laser litografie neergelê is. Toets van die SQUID het ’n niehisterese stroom-spanning as kenmerkend getoon. Die nader bring en terugtrekking van ’n magneet het gelei tot waarneming van die modulasie van die I-V kurwe. Die kritieke stroom van die SQUID was 20 A en die weerstand was 5.5 ohm. ’n Reeks eksperimente is uitgevoer oor vernietigende metings van die suikerinhoud van tafeldruiwe met gebruik van NMR, om die gangbaarheid van hierdie tegniek te evalueer. Totale suikers (TSS) metings van dieselfde monsters is uitgevoer deur refraktometrie, wat gekies is as gebruiklike metode vir geldigheidsbepaling. Die NMR metings is as 5.4% presies/noukeurig evalueer, en met ’n akkuraatheid van 9.3% teenoor die refraktometrie metingsyfers. ’n Verdere reeks eksperimente is uitgevoer op ’n hoë-Tc SQID-NMR stelsel. ’n Hoë korrelasiekoëffisiënt van 0.85 van die toenemende waardes van T1 en T2 ontspantye teenoor die afname in konsentrasie van sukrose in water is waargeneem. Nie-vernietigende metings van T1 eb T2 in tafeldruiwe het gelei tot die moontlikheid van gebruik van hierdie tegniek om suikerinhoud van tafeldruiwe te voorspel. Die tegniek het ook baie voordele getoon in teenstelling met die gebruiklike hoëveld NMR tegniek, onder andere dat hierdie metings vinniger is, nie verdere verwerking van die spektrum benodig nie, die maklike voorbereiding van die monsters en die nie-vernietigende aard van die proses.
24

Influence of polliniser position and honeybee colony distance in the set and quality of deciduous fruit in the Western Cape

Ramongalo, Boipelo Kgomotsego 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2010. / Thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Stellenbosch University. / ENGLISH ABSTRACT: Most modern deciduous fruit cultivars are self-incompatible, and require polliniser trees to be planted in the orchard to provide the pollen necessary for cross-pollination, fertilization and fruit set. Polliniser trees are either non-commercial cultivars interspersed in the orchard solely to provide pollen, or crosscompatible cultivars inter-planted in the same orchard. 90% of the commercial crops dependent on bee pollination are courtesy of a single species, Apis mellifera. Both polliniser planting pattern and honey bee colony distance are known to influence crop production and crop quality, resulting in a rapid decrease in fruit weight, fruit set and seed number with increasing distance from the polliniser or honeybee colonies. However, the response of different crops and cultivars to polliniser and pollinator proximity on optimal crop yield is not known for deciduous fruit crops in the Western Cape, South Africa. The effect of polliniser position and honeybee colony distance on fruit set and weight was investigated in plums, apples and pears on the Lourensford Estate. The relationship between fruit set and fruit weight was investigated for deciduous fruit cultivars. In addition, fruit weight and seed number was also investigated in apples and pears. Fruit set tended to increase on sides of trees closer to the polliniser but not significantly so, except for apples. This suggests that there is probably better pollination closer to the pollinisers but this does not equate to increased yield. In fact, smaller fruit was produced on the sides of the trees closer to the polliniser for all orchards and significantly so for plum and for ‘Packham’s Triumph’ in Hillside 1. This negative relationship between fruit set and weight may indicate ‘over-set’ beyond the physiological limits of the trees. Fruits closer to the polliniser had significantly more seeds for both pear and apple cultivars indicating sufficient pollination. A significant relationship was found between the seed number in any particular fruit and the weight of the fruit in all the cultivars except ‘Packham’s Triumph’ where the relationship was negative, suggesting that ‘Packham’s Triumph’ set parthenocarpically. Colony distance had no effect on fruit weight, fruit set and on seed number indicating that colonies were adequately distributed and that there was no “pollination depression” in the centre of the orchards at Lourensford. In conclusion, the fact that we did not get a yield gradient with increased distance from the colonies suggested that the orchards at Lourensford Estate were sufficiently pollinated. / AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar
25

Non-destructive prediction and monitoring of postharvest quality of citrus fruit

Magwaza, Lembe Samukelo 12 1900 (has links)
Thesis (PhD(Agric))--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The aim of this study was to develop non-destructive methods to predict external and internal quality of citrus fruit. A critical review of the literature identified presymptomatic biochemical markers associated with non-chilling rind physiological disorders. The prospects for the use of visible to near infrared spectroscopy (Vis/NIRS) as non-destructive technology to sort affected fruit were also reviewed. Initial studies were conducted to determine the optimum condition for NIRS measurements and to evaluate the accuracy of this technique and associated chemometric analysis. It was found that the emission head spectroscopy in diffuse reflectance mode could predict fruit mass, colour index, total soluble solids, and vitamin C with high accuracy. Vis/NIRS was used to predict postharvest rind physico-chemical properties related to rind quality and susceptibility of ‘Nules Clementine’ to RBD. Partial least squares (PLS) statistics demonstrated that rind colour index, dry matter (DM) content, total carbohydrates, and water loss were predicted accurately. Chemometric analysis showed that optimal PLS model performances for DM, sucrose, glucose, and fructose were obtained using models based on multiple scatter correction (MSC) spectral pre-processing. The critical step in evaluating the feasibility of Vis/NIRS was to test the robustness of the calibration models across orchards from four growing regions in South Africa over two seasons. Studies on the effects of microclimatic conditions predisposing fruit to RBD showed that fruit inside the canopy, especially artificially bagged fruit, had lower DM, higher mass loss, and were more susceptible to RBD. The study suggested that variations in microclimatic conditions between seasons, as well as within the tree canopy, affect the biochemical profile of the rind, which in turn influences fruit response to postharvest stresses associated with senescence and susceptibility to RBD. Principal component analysis (PCA) and PLS discriminant analysis (PLS-DA) models were applied to distinguish between fruit from respectively, inside and outside tree canopy, using Vis/NIRS signal, suggesting the possibility of using this technology to discriminate between fruit based on their susceptibility to RBD. Results from the application of optical coherence tomography (OCT), a novel non-destructive technology for imaging histological changes in biological tissues, showed promise as a potential technique for immediate, real-time acquisition of images of rind anatomical features of citrus fruit. The study also demonstrated the potential of Vis/NIRS as a non-destructive tool for sorting citrus fruit based on external and internal quality. / AFRIKAANSE OPSOMMING: Die studie het ten doel gestaan om nie-destruktiewe meeting metodes te toets en ontwikkel wat die interne en eksterne-kwaliteit van sitrusvrugte kan voorspel. In ʼn litratuuroorsig is biochemies verandering in die skil en wat geassosieer word met die ontwikkeling van fisiologies skildefekte geïdentifiseer, asook is die moontlikheid ondersoek om Naby Infrarooi spektroskopie (NIRS) as ‘n nie-destruktiewe tegnologie te gebruik om vrugte te sorteer. Eerstens was die optimale toestande waarby NIRS meetings van sitrusvrugte geneem moet word asook die akkuraatheid van die toerusting en chemometrika data-ontleding beproef. Daar is gevind dat die uitstralings-kop spektrofotometer in diffusie-weerkaatsings modus vrugmassa, skilkleur, totale opgeloste stowwe asook vitamien C akkuraat kan voorspel. Daarna van NIRS gebruik om na-oes fisies-chemiese eienskappe wat verband hou met skilkwaliteit en vatbaarheid vir skilafbraak van ‘Nules Clementine’ mandaryn. Deur gebruik te maak van “Partial least squares” (PLS) statistieke was gedemonstreer dat die skilkleur, droë massa (DM), totale koolhidrate en waterverlies akkuraat voorspel kon word. Chemometriese analises het ook getoon dat optimale PLS modelle vir DM, sukrose, glukose en fruktose verkry kan word deur modelle te skep wat gebaseer is op “Multiple scatter correction” (MSC) spektrale voor-verwerking. ʼn Belangrike stap in die ontwikkeling van NIRS gebaseerde indeling is om die robuustheid van die kalibrasiemodelle te toets en was gedoen deur vrugte te meet en sorteer van vier boorde en oor twee seisoene. ʼn Verder eksperiment om die impak van mikroklimaat op die skil se vatbaarheid vir fisiologiese defekte te ontwikkel het getoon dat vrugte wat binne in die blaardak ontwikkel (lae vlakke van sonlig) ʼn laer DM, hoër gewigsverlies het en was ook meer vatbaar vir skilafbraak. Die resultate dui daarop dat verskille in mikroklimaat oor die seisoen asook in die blaardak die skil se biochemiese profiel beïnvloed, wat lei tot ʼn negatiewe reaksie op na-oes stres en verhoogde voorkoms van fisiologiese skilafbraak. Die ontwikkelde “Principal component analysis” (PCA) en PLS-diskriminant analise modelle was daarna suksesvol toegepas om vrugte te skei na NIRS meetings, op die basis van vrugpossies in die blaardak. Nuwe, nie-destruktiewe tegniek, nl. “Optical coherence tomography” (OCT) was suksesvol getoets as manier om ʼn fotografiese beeld te skep van histologiese veranderinge in die skil. Die resultate dui op die potensiaal van die onontginde tegnologie om intak biologiese-materiaal te analiseer. Hierdie studie het getoon dat daar wesenlike potensiaal is om NIRS verder te ontwikkel tot ʼn tegnologie wat gebruik kan word om vrugte te sorteer gebaseer op eksterne (skil) asook interne (pulp) eienskappe
26

Desempenho agronômico de novas cultivares de bananeira (Musa spp.) na região de Piracicaba-SP / Agronomic performance of new banana cultivars (Musa spp.) at Brazil subtropical region, Piracicaba-SP

Rosa, Andréa Ribeiro Domingues 22 February 2016 (has links)
O estado de São Paulo destaca-se como o maior produtor nacional de banana (Musa spp.), com sua produção comercial tradicionalmente concentrada na região do Vale do Ribeira e no Litoral Paulista. No entanto, os cultivos se estenderam a partir da década de 1990 para o Planalto Paulista, onde agricultores buscavam uma maior diversificação das atividades agrícolas. A prevalência do cultivo com cultivares tradicionais tem sido desafiadora devido à suscetibilidade dessas às principais doenças. Objetivou-se avaliar dois novos híbridos tetraplóides (AAAB) resistentes à Sigatoka amarela (Mycosphaerella musicola, Leach), a \'BRS Platina\' e a \'BRS Princesa\', comparando-os com a cultivar comumente utilizada, a \'Prata-anã\' (AAB). No entanto, a adoção de novos híbridos de bananeira não se estabelece apenas pela sua resistência às doenças. Dessa forma, variáveis vegetativas, variáveis de rendimento do cacho e suas correlações, duração do ciclo e qualidade pós-colheita dos frutos também foram avaliadas. O experimento foi conduzido no município de Piracicaba-SP (latitude: 22 43\' 30\'\' S, longitude de 47 38\' 56\'\' O e altitude de 554 metros), que possui clima classificado como Cwa, com chuva predominante no verão e período mais seco e frio no inverno. O delineamento experimental foi o de blocos ao acaso, com a adoção de três repetições e a parcela composta por três plantas. Quanto às avaliações da qualidade pós-colheita dos frutos, o delineamento experimental adotado foi o inteiramente casualizado, 12 dias de armazenamento, três repetições, cada qual constituída por três frutos. Os resultados foram submetidos à análise estatística de variância e ao teste de Tukey a 5% de significância; análise de correlação com base na correlação de Pearson e análise de regressão a 5% de significância. De acordo com os resultados obtidos, conclui-se que as cultivares BRS Platina e BRS Princesa apresentam maior resistência à Sigatoka amarela em relação à cultivar Prata-anã, porém não diferem quanto ao rendimento do cacho. Quanto ao crescimento vegetativo, destaca-se o maior porte apresentado pelas novas cultivares, BRS Platina e BRS Princesa, podendo conferir às essas cultivares maior suscetibilidade ao tombamento, principalmente devido a frequência de ventos fortes na região. Em relação ao ciclo de produção as cultivares não diferem entre si. Quanto à qualidade pós-colheita dos frutos, as bananas \'BRS Platina\' apresentam um amadurecimento mais acelerado e, consequentemente, senescência dos frutos. Somente a cultivar BRS Platina apresenta correlação positiva entre variáveis vegetativas e produção. / São Paulo state stands out as the main producer of banana (Musa spp.). The commercial production is mostly concentrated at Vale do Ribeira region and São Paulo coast. However, at the 1990 decade Banana cultivation started spreading towards the Paulista plateau where farmers sought cropping diversification. Maintaining the use of traditional cultivars has been challenging due to their susceptibility to main diseases.This study aimed evaluating two recently breed tetraploids hybrids (AAAB), \'BRS Platina\' and \'BRS Princesa\' resistant to yellow Sigatoka (Mycosphaerella musicola, Leach), comparing it to the commonly used \'Prata-anã\' cultivar (AAB). Knowing that the adoption of a new hybrid does not take place by simply considering its resistance to diseases, the evaluation of vegetative parameters, bunch yield and its correlations, cycle duration and post-harvest quality of the fruits were necessary. The study was installed in Piracicaba-SP (latitude: 22 43\' 30\'\' S, longitude de 47 38\' 56\'\' W e altitude of 554 meters), with Cwa climate classification where most rain occurs during summer and the winter is dry and cold. The adopted experimental desing was randomized blocks, with three replicates and three plants per plot. The post-harvest evaluations took place in a complete randomized desing, with three replicates and plots composed of three bananas. The results were submitted to analysis of variance and Tukey test at the level of 5% of significance; Pearson correlation analysis and regression analysis. The most valuable results related, the \'BRS Platina\' and \'BRS Princesa\' demonstre higher resistance to yellow Sigatoka when compared to \'Prata-anã\' but there are no difference in yield as a result of the components of the bunch of each cultivar. The news cultivars have pseudostem taller than \'Prata-anã\'. In terms of post-harvest quality, bananas \'BRS Platina\' has early fruit maturation, when compared to the others, and consequently sooner beginning off fruit decease process. Only the \'BRS Platina\' has positive correlation between vegetative and production parameters.
27

Estudos da maturação do fruto e das sementes de Physalis peruviana L. e do teste de germinação / Studies on the maturation of the fruit and seeds of Physalis peruviana L. and germination test

Diniz, Fábio Oliveira 04 December 2018 (has links)
O cultivo de fisális (Physalis peruviana L.) é uma alternativa promissora para os agricultores que se dedicam à produção de frutíferas exóticas, do segmento de \"pequenas frutas\", em decorrrência da valorização do fruto, que possue diversas qualidades organolépticas e funcionais. Entretanto, ainda são escassas as informações sobre a cultura nas condições edafoclimáticas brasileiras, especialmente em relaçao aos processos de maturação dos frutos e das sementes, de modo que possa ser indicado o momento adequado para a colheita, considerando a qualidade dos frutos e das sementes e, não menos importante, o estudo das condições ideais para o teste de germinação das sementes, uma vez que, este teste, além de ser empregado para auxiliar na identificação da maturidade fisiológica das sementes, seus resultados são parâmetro para comparação da qualidade das sementes dos lotes e para a comercialização das sementes. Portanto, a presente pesquisa foi realizada com os objetivos de avaliar as necessidades de luz, temperatura e substrato para o teste de germinação; estudar a maturação dos frutos e das sementes e, a incidência de fungos nas sementes de Physalis peruviana L., segundo o momento do florescimento da planta e a idade dos frutos. Desta forma, a pesquisa foi conduzida entre fevereiro de 2016 e novembro de 2017, nos Laboratórios Análise de Sementes (LAS), de Análise de Imagens (LAI), de Pós-Colheita de Produtos Hortícolas (LPCPH) e de Patologia de Sementes (LPS), pertencentes aos Departamentos de Produção Vegetal e de Fitopatologia e Nematologia, da Escola Superior de Agricultura \"Luiz de Queiroz\", Universidade de São Paulo (USP, ESALQ), em Piracicaba, São Paulo. Para os estudos do teste de germinação das sementes, primeirameite foram avaliados diferentes suprimentos de luz e temperatura, sendo utilizada uma mesa termogradiente regulada com nove intervalos de temperatura (variação de 15 °C a 35 °C) e duas alternadas 20-30 °C e 15-35 °C, com oito horas de fotoperíodo e na ausência total de luz. Após estabelecidos os requerimentos de luz e temperatura, foram estudados os substratos para germinação das sementes: papel mata-borrão (sobre papel), areia (entre areia) e vermiculita (entre vermiculita). Quanto aos estudos da maturação e análise sanitária, foram distinguidos dois momentos de florescimento das plantas, 55 e 105 dias após o transplante (DAT) e, em cada um destes momentos, as flores foram marcadas por ocasião da antese e os respectivos frutos e sementes avaliados aos 45, 60, 75 e 90 dias após (DAA). A germinação das sementes de Physalis peruviana L. ocorre em intervalo amplo de temperatura (15 a 30,2 °C), sendo ideais as temperaturas 25 °C constante e 20-30 °C alternada, com oito horas de luz. O substrato areia (entre areia) é mais adequado e, como alternativa, podem ser utilizados o papel (sobre papel) e a vermiculita (entre vermiculita). As avaliações do teste de germinação podem ser realizadas no 7º dia (primeira contagem) e no 14º dia (contagem final) após a instalação do teste. O momento do florescimento e o estádio de desenvolvimento do fruto têm influência sobre as características qualitativas deste e sobre a maturação das sementes. A idade (em dias após a antese) e as modificações da cor, da massa, do tamanho e do sabor que ocorrem durante o desenvolvimento são parâmetros indicativos da maturidade fisiológica tanto do fruto quanto das sementes, as quais ocorrem aos 75 DAA (55 DAT) e aos 60 DAA (105 DAT). Além disso, os frutos produzidos em Piracicaba, São Paulo, têm padrão para a comercialização e qualidade similar a dos frutos produzidos em outras regiões de cultivo. Os gêneros fúngicos constatados em sementes de Physalis peruviana L. são Alternaria, Aspergillus, Bipolaris, Cladosporium, Epicoccum, Fusarium, Nigrospora e Penicillium, sendo a menor incidência em sementes de 75 DAA. A presença dos fungos não afeta o componente fisiológico das sementes. / The cultivation of cape gooseberry (Physalis peruviana L.) is a promising alternative for the farmers who are dedicated to the production of exotic fruit, the \"small fruits\" segment, due to the valorization of the fruit, which has several organoleptic and functional qualities. However, information about the crop under Brazilian soil and climate conditions is still scarce, especially in relation to the fruit and seed maturation processes, so that the appropriate time for harvest can be indicated, considering the quality of the fruits and seeds and, not least, the study of the ideal conditions for the seed germination test, since this test, besides being used to help in the identification of the physiological maturity of the seeds, yours results are parameter for comparison the seed quality of the lots and for seed marketing. Therefore, the present research was developed out with the objective of evaluating the light, temperature and substrate requirements for the germination test and to study the maturation of fruits and seeds, and the incidence of fungi on seed of Physalis peruviana L., according to the moment of flowering of the plant and fruit age. The research was conducted between february 2016 and november 2017, in the Laboratories of Seeds Analysis (LAS), Analysis of Images (LAI), Post-Harvesting of Horticultural Plants (LPCPH) and Pathology Seeds (LPS), belonging to the Departments of Crop Science and Phytopathology and Nematology, Luiz de Queiroz College of Agriculture, University of São Paulo (USP/ESALQ), in Piracicaba, São Paulo. For the seed germination test, different light and temperature supplies were evaluated first, using a termo-gradient table regulated with nine temperature ranges (ranging from 15 °C to 35 °C) and two alternate 20-30 °C and 15-35 °C, with eight hours of photoperiod and in the total absence of light. After the light and temperature requirements were established, the substrates for seed germination were studied: blotter paper sheets (upon paper), sand (between sand) and vermiculite (between vermiculite). In the maturation and seed health studies, two flowering moments were considered, at 55 and 105 days after transplanting (DAT) of the plants, and in each of these moments, the flowers were marked in the anthesis and the respective fruits and seeds evaluated at 45, 60, 75 and 90 days after anthesis (DAA).The germination of the seeds of Physalis peruviana L. occurs in a wide temperature range (15 to 30,2 °C), with temperatures 25 °C constant and 20-30 °C alternating, with eight hours of light. The sand substrate (between sand) is more suitable and, alternatively, paper and vermiculite may be used. The germination test evaluations can be performed on the 7th day (first count) and on the 14th day (final count) after the test installation. The moment of flowering and the development stage of the fruit influence the qualitative characteristics of the fruit and the maturation of the seeds. The age (in days after anthesis) and changes in color, mass, size and flavor that occur during the development, are indicative parameters of the physiological maturity of both fruit and seeds, which occur at 75 DAA (55 DAT) and at 60 DAA (105 DAT). In addition, fruits produced in Piracicaba, São Paulo, has a commercial pattern and quality similar to the fruits produced in other regions. The fungal genus found in seeds of Physalis peruviana L. are Alternaria, Aspergillus, Bipolaris, Cladosporium, Epicoccum, Fusarium, Nigrospora and Penicillium, the lowest incidence occurring in seeds of 75 DAA. The presence of fungi does not affect the physiological component of the seeds.
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Fenologia e qualidade de frutos de nespereira / Fenology and fruit quality of Loquat

Grassi, Alexandre Manzoni 29 August 2008 (has links)
A nespereira é uma planta rústica, que prescinde da utilização sistemática de defensivos, o que torna o cultivo atraente, para atender ao público que cresce, dia a dia, à procura de produtos naturais.O trabalho teve por objetivo realizar a caracterização fenológica da nespereira, estabelecendo os estádios fenológicos e o ciclo de produção de 5 cultivares e de uma seleção.Também estudou-se a melhor fase para o ensacamento dos frutos e a intensidade de raleio para a obtenção de frutos de alta qualidade. Foi estabelecida uma escala fenológica contendo sete estádios de desenvolvimento para a nespereira. Os estágios observados foram: 0 Desenvolvimento da Gema; 1 Desenvolvimento das folhas; 3 Desenvolvimento dos Brotos; 5 Emergência da Inflorescência; 6 Florescimento; 7 Desenvolvimento dos frutos; 8 Maturação dos frutos, de acordo com a escala BBCH. Mediante o estudo da escala fenológica das 5 cultivares e da seleção IAC NE3, verificou-se a existência de diferenças no ciclo de produção das cultivares estudadas e também da seleção, possibilitando a observação de três grupos. O primeiro grupo, mais precoce, foi formado pelas cultivares Mizuho e Mizumo, com ciclo médio de 195 dias contados a partir do início do desenvolvimento das gemas até a colheita dos frutos. As cultivares Néctar de Cristal e Centenária formaram um segundo grupo apresentando um ciclo intermediário com uma média de 203 dias. Já a cultivar Mizauto e a seleção IAC NE3 foram as mais tardias, uma vez que o ciclo foi concluído 208 dias, em média, após o início do desenvolvimento das gemas.A intensidade de raleio a ser adotada deve ser de 4 ou 6 frutos por panícula, levando-se em conta a safra esperada; o ensacamento dos frutos deve ser realizado nos estádios 1 (frutos com 1,0 cm de diâmetro) ou 2 (frutos com 1,5 cm de diâmetro). / The Loquat is a rustic plant, which renounce the systematic use of defensive, which makes the cultivation attractive, to attend the public that grows, day by day, the demand for natural products. The study aimed to carry out the phenological characterization of loquat, setting the phenological stages and the cycle of production of 5 cultivars and a selection. Also studied is the best stage for the bagging of panicles and thinning intensity for obtaining fruits of high quality. Was established a scale containing seven phenological stages of development for loquat. The stages were observed: 0 - Development of bud, 1 - Development of the leaves, 3 - Development of shoot, 5 - Emergency of Inflorescence, 6 - Blooming; 7 - Development of fruit; 8 - Ripening fruits, according to the scale BBCH. Through the study of phenological scale from 5 cultivars and selection IAC NE3, there are differences in the production cycle of cultivars and the selection, enabling the observation of three groups. The first group, earlier, was formed by cultivars with Mizuho and Mizumo cycle average of 195 days counted from the beginning of the development of buds until the harvest fruit. Cultivars nectar of Cristal and Centenária formed a second group presenting a cycle intermediary with an average of 203 days. The cultivar Mizauto and the select IAC NE3 were the most late, since the cycle was completed 208 days on average after the start of the development of buds. The intensity of thinning to be used must be 4 or 6 fruits per raceme, considering the crop waited and the fruit price in the market. The fruit bagging must be realized in the harvest time 1(fruits with 1,0 cm of diameter) or 2(fruits with 1,5 cm of diameter).
29

Caracterização de determinantes genéticos envolvidos na qualidade industrial e nutricional do fruto de tomate / Characterization of genetic determinants involved in industrial and nutritional quality of tomato fruit

Salazar, Luisa Fernanda Bermúdez 11 August 2011 (has links)
A presente tese aborda o estudo do metabolismo dos frutos de tomate a partir de três estratégias complementares: i) a identificação de genes candidatos colocalizados com QTL, previamente descritos a partir do perfil metabólico de S. lycopersicum (cv. M82) e linhagens introgredidas de S. pennellii, associados ao conteúdo de metabólitos de interesse industrial e nutricional; ii) a análise estrutural das regiões genômicas portadoras desses genes; e iii) a análise funcional dos genes chaperona DnaJ e sec14 por meio de genética reversa mediante o silenciamento por RNAi. A análise de marcadores moleculares previamente mapeados nas regiões portadoras dos QTL permitiu identificar 127 genes candidatos cujos produtos foram mapeados nas rotas metabólicas correspondentes. Um subgrupo desses genes apresentou diferenças alélicas entre os progenitores da população utilizada para a identificação dos QTL. A análise de microssintenia revelou um alto grau de conservação na estrutura genômica, apresentando polimorfismos nas regiões codificantes e regulatórias, assim como no padrão de inserção de elementos de transposição. Baseado nessas diferenças, análises de expressão e funcionalidade putativa, dois genes foram escolhidos para a análise funcional utilizando a estratégia de RNA de interferência. Os resultados obtidos da avaliação fenotípica das plantas deficientes em chaperona DnaJ permitiram concluir que esta proteína, localizada nos cloroplastos, participa da regulação do metabolismo de açúcares, em particular na síntese de amido, controlando assim, a exportação de fotoassimilados. Já, a caracterização das linhagens silenciadas para o gene sec14, levou a postular que os conteúdos de tocoferol (VTE) nos frutos de tomate, não só dependem da regulação cinética das enzimas envolvidas na sua síntese, mas também da função da proteína do SEC14, não caracterizada em plantas até o momento. Essa proteína estaria envolvida no transporte de VTE entre os diferentes compartimentos do cloroplasto tendo impacto no equilíbrio oxidativo, na estrutura do plastídeo e, consequentemente, na biossíntese desta vitamina. Os resultados obtidos nesta tese reforçam a hipótese que o germoplasma selvagem constituem uma fonte de variabilidade a ser explorada para a identificação de determinantes genéticos que viabilizem novas estratégias de melhoramento de tomate por meio da manipulação do metabolismo central dos frutos. / This thesis addresses tomato fruit metabolism analysis by using three complementary approaches: i) the identification of candidate genes co-located with QTL previously described from metabolic profiles of S. lycopersicum (cv. M82) and S. pennellii introgressed lines, associated with industrial and nutritional quality traits; ii) the structural analyses of the genomic regions harboring the identified genes and ; iii) the functional analysis of the chaperone DnaJ and sec14 genes through reverse genetics mediated by iRNA silencing. The analysis of the molecular markers previously mapped onto the QTL-associated regions allowed the identification of 127 candidate genes whose products were mapped in the corresponding metabolic pathways. A subset of these genes showed allelic differences between the parental genotypes used for QTL identification. Based on these differences, together with the expression profile analysis and their putative function, two genes were selected for functional analysis using RNA interference approach. The phenotypic profile of the chaperone DnaJ deficient plants allowed to conclude that this protein, located in chloroplasts, participates in sugar metabolism, in particular, starch synthesis, controlling assimilates partitioning. The characterization of sec14-silenced transgenic lines leads to propose that fruit tocopherol (VTE) contents not only depend on the kinetic regulation of the biosynthesis-involved enzymes, but also on the SEC14 action, not yet characterized in plants. This protein might be involved in VTE transport between the different plastidial compartments thus, affecting oxidative balance, chloroplast structure and, consequently, VTE biosynthesis. All together these results support the hypothesis that wild germoplasm represents a remarkable source of variability to be explore aiming the identification of genetic determinants to develop new breeding approaches for tomato through metabolic engineering.
30

Caracterização de determinantes genéticos envolvidos na qualidade industrial e nutricional do fruto de tomate / Characterization of genetic determinants involved in industrial and nutritional quality of tomato fruit

Luisa Fernanda Bermúdez Salazar 11 August 2011 (has links)
A presente tese aborda o estudo do metabolismo dos frutos de tomate a partir de três estratégias complementares: i) a identificação de genes candidatos colocalizados com QTL, previamente descritos a partir do perfil metabólico de S. lycopersicum (cv. M82) e linhagens introgredidas de S. pennellii, associados ao conteúdo de metabólitos de interesse industrial e nutricional; ii) a análise estrutural das regiões genômicas portadoras desses genes; e iii) a análise funcional dos genes chaperona DnaJ e sec14 por meio de genética reversa mediante o silenciamento por RNAi. A análise de marcadores moleculares previamente mapeados nas regiões portadoras dos QTL permitiu identificar 127 genes candidatos cujos produtos foram mapeados nas rotas metabólicas correspondentes. Um subgrupo desses genes apresentou diferenças alélicas entre os progenitores da população utilizada para a identificação dos QTL. A análise de microssintenia revelou um alto grau de conservação na estrutura genômica, apresentando polimorfismos nas regiões codificantes e regulatórias, assim como no padrão de inserção de elementos de transposição. Baseado nessas diferenças, análises de expressão e funcionalidade putativa, dois genes foram escolhidos para a análise funcional utilizando a estratégia de RNA de interferência. Os resultados obtidos da avaliação fenotípica das plantas deficientes em chaperona DnaJ permitiram concluir que esta proteína, localizada nos cloroplastos, participa da regulação do metabolismo de açúcares, em particular na síntese de amido, controlando assim, a exportação de fotoassimilados. Já, a caracterização das linhagens silenciadas para o gene sec14, levou a postular que os conteúdos de tocoferol (VTE) nos frutos de tomate, não só dependem da regulação cinética das enzimas envolvidas na sua síntese, mas também da função da proteína do SEC14, não caracterizada em plantas até o momento. Essa proteína estaria envolvida no transporte de VTE entre os diferentes compartimentos do cloroplasto tendo impacto no equilíbrio oxidativo, na estrutura do plastídeo e, consequentemente, na biossíntese desta vitamina. Os resultados obtidos nesta tese reforçam a hipótese que o germoplasma selvagem constituem uma fonte de variabilidade a ser explorada para a identificação de determinantes genéticos que viabilizem novas estratégias de melhoramento de tomate por meio da manipulação do metabolismo central dos frutos. / This thesis addresses tomato fruit metabolism analysis by using three complementary approaches: i) the identification of candidate genes co-located with QTL previously described from metabolic profiles of S. lycopersicum (cv. M82) and S. pennellii introgressed lines, associated with industrial and nutritional quality traits; ii) the structural analyses of the genomic regions harboring the identified genes and ; iii) the functional analysis of the chaperone DnaJ and sec14 genes through reverse genetics mediated by iRNA silencing. The analysis of the molecular markers previously mapped onto the QTL-associated regions allowed the identification of 127 candidate genes whose products were mapped in the corresponding metabolic pathways. A subset of these genes showed allelic differences between the parental genotypes used for QTL identification. Based on these differences, together with the expression profile analysis and their putative function, two genes were selected for functional analysis using RNA interference approach. The phenotypic profile of the chaperone DnaJ deficient plants allowed to conclude that this protein, located in chloroplasts, participates in sugar metabolism, in particular, starch synthesis, controlling assimilates partitioning. The characterization of sec14-silenced transgenic lines leads to propose that fruit tocopherol (VTE) contents not only depend on the kinetic regulation of the biosynthesis-involved enzymes, but also on the SEC14 action, not yet characterized in plants. This protein might be involved in VTE transport between the different plastidial compartments thus, affecting oxidative balance, chloroplast structure and, consequently, VTE biosynthesis. All together these results support the hypothesis that wild germoplasm represents a remarkable source of variability to be explore aiming the identification of genetic determinants to develop new breeding approaches for tomato through metabolic engineering.

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