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Influence of bagging materials on maturity indices and post-harvest quality of 'roma vf' and 'tinker' cherry tomatoesMafotja, 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
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Irrigation scheduling of tomatoes (Lycopersicon esculentum Mill.) and cucumbers (Cucumis sativus L.) grown hydroponically in coirVan der Westhuizen, Rykie Jacoba 12 1900 (has links)
Thesis (PhD(Agric) (Agronomy))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The use of capacitance water sensors for the scheduling of irrigation for hydroponic tomato and
cucumber crops grown in coir was investigated in a series of laboratory and glasshouse experiments
in the Free State province of South Africa.
Laboratory experiments in a climate controlled chamber were conducted to accurately calibrate
ECH2O capacitance sensors, models EC-10 and EC-20, in coir with an improved calibration
procedure. Water content predictions by the coir-specific calibration and manufacturer’s calibration
equations were compared to actual water content measured from mass loss of the coir sample. The
manufacturer’s calibration equation indicated a poor accuracy of prediction, which mostly
underestimated the volumetric water content, compared to the near perfect prediction of the
coir-specific calibration of individual sensors. A rapid calibration procedure for EC-10 and EC-20
sensors was proposed to reduce the calibration time of the sensors and promote their commercial
use for irrigation management in coir. The accuracy of prediction by the rapid calibration procedure
for the plant available water content range was high for both EC-10 and EC-20 sensors and allowed
for the compensation for variation between sensors.
Glasshouse studies aimed to characterise the water retention and ability of coir to supply water to
greenhouse tomato and cucumber crops through the continuous monitoring of medium water
content in small and large growing bags with the EC-10 and EC-20 capacitance sensors during a
drying cycle, compared to well-watered plants. Stages of crop water stress were identified and,
based only on the plant’s response to the drying cycle, it was suggested that water depletion can be
allowed to the point of mild water stress for both greenhouse tomato and cucumber crops, which can
be detected by soil water sensors. In a second series of glasshouse experiments, the identified stages
of crop water stress were used to determine and apply depletion levels in coir and compare this
irrigation strategy to a well-watered treatment for greenhouse cucumber and tomato plants, with
regard to the water balance components, yield and water use efficiency for different bag sizes.
Results indicated that irrigation was successfully managed to the pre-determined water depletion
levels for cucumber and tomato plants in coir, through the use of in situ calibrated capacitance
sensors. For both crops the depletion of water varied between bag sizes, indicating that various bag
sizes require different irrigation management strategies. Scheduling to the highest pre-determined by 124 L m-2 in the small and 240 L m-2 in the large bags for
cucumbers and 427 L m-2 in the small and 487 L m-2 in the large bags for tomato plants, compared
to the well-watered treatments. Yields achieved by the greenhouse tomato plants in the large
growing bags and cucumber plants in the small and large bags were maintained or improved when
scheduled to the highest depletion level (approximately 60% available water content) compared to
the well-watered treatment. The combination of reduced irrigation and improved or maintained
yields resulted in improved water use efficiencies (based on irrigation and transpiration) for the
highest depletion level compared to the well-watered treatments. In all glasshouse experiments the
well-watered treatment resulted in luxury water use by the plants.
Finally, a study was conducted in order to compare crop water stress of greenhouse cucumber and
tomato plants under luxury water supply and cyclic water deficit conditions. The comparison was
based on the transpiration ratio and yield, while the use of capacitance sensors was evaluated for
irrigation scheduling in coir for both crops. Transpiration data indicated that cucumber and tomato
plants subjected to luxury water supply experience water stress earlier than plants subjected to
cyclic water deficit conditions, irrespective of bag size. Results also indicated that irrigation
scheduling according to water depletion levels in small bags is not yet recommended for greenhouse
tomato and cucumber plants grown in coir, until further research is conducted. Scheduling to water
depletion levels in large bags is, however, justified by the improved or maintained yields of the
greenhouse cucumber and tomato plants. The estimated depletion levels for large bags beyond
which yield are reduced was at 85% for tomatoes and 70% for cucumbers.
In conclusion, the results clearly indicated that the use of capacitance sensors in large growing bags
improves irrigation management of hydroponic cucumbers and tomatoes in coir by eliminating
over-irrigation and improving water use efficiency. More research is needed before a conclusion can
be made regarding irrigation scheduling with capacitance sensors in small growing bags. / AFRIKAANSE OPSOMMING: Die gebruik van kapasitansie water sensors vir besproeiingskedulering van tamatie en komkommer
plante wat hidroponies in kokosveen gegroei is, is ondersoek in ‘n reeks laboratorium en glashuis
eksperimente in die Vrystaat provinsie van Suid Afrika.
Laboratorium eksperimente is uitgevoer in ‘n klimaat beheerde kas om ECH2O kapasitansie sensors,
modelle EC-10 en EC-20, akkuraat te kalibreer vir kokosveen deur ’n verbeterde kalibrasie
prosedure. Waterinhoud voorspellings deur die kokosveen spesifieke kalibrasie en die vervaardiger
se kalibrasie vergelykings is vergelyk met die werklike waterinhoud wat gemeet is deur die
kokosveen monster se massaverlies te monitor. Akkuraatheid van voorspelling deur die
vervaardiger se kalibrasie vergelykings was swak en het meestal die volumetriese waterinhoud
onderskat in vergelyking met die byna perfekte voorspelling deur die kokosveen spesifieke
kalibrasie van individuele sensors. ’n Vinnige kalibrasie prosedure vir die EC-10 en EC-20 sensors
is voorgestel om die kalibrasie tyd te verkort en die kommersiële gebruik van die sensors vir
besproeiingsbestuur in kokosveen aan te moedig. Die akkuraatheid van voorspelling deur die
vinnige kalibrasie prosedure, binne die grense van plant beskikbare waterinhoud, was hoog vir beide
EC-10 en EC-20 sensors, terwyl die prosedure ook voorsiening maak vir variasie tussen sensors.
Glashuis studies is uitgevoer om die water retensie en vermoë van kokosveen om water te voorsien
aan tamatie en komkommer gewasse in kweekhuise, te karakteriseer. Dit is bereik deur die
mediumwaterinhoud van klein en groot plantsakke deurlopend te monitor met behulp van die EC-10
en EC-20 kapasitansie sensors gedurende ’n uitdroging siklus, en dit te vergelyk met ’n waterryke
behandeling vir elke gewas waarvolgens die plante agt keer per dag besproei is. Fases van gewas
waterstremming is geïdentifiseer en, volgens die reaksie van die plant tot die drogingsiklus, is dit
voorgestel dat wateronttrekking toegelaat kan word tot die punt van matige waterstremming wat
aangewys kan word deur kapasitansie water sensors vir beide kweekhuis tamatie en komkommer
gewasse. In ’n tweede reeks glashuis eksperimente is die geïdentifiseerde fases van gewas
waterstremming gebruik om onttrekkingsvlakke vir kokosveen te bepaal en toe te pas as
besproeiingskeduleringstrategie vir kweekhuis komkommer en tamatie plante. Toegepaste vlakke is
vir elke gewas vergelyk met ’n waterryke behandeling ten opsigte van die waterbalans komponente,
opbrengs en watergebruiksdoeltreffendheid in verskillede sakgroottes. Resultate het aangedui dat
besproeiing suksesvol bestuur is tot die voorafbepaalde wateronttrekkingsvlakke vir komkommer entamatie plante in kokosveen, deur gebruik te maak van in situ gekalibreerde kapasitansie sensors.
Die onttrekking van water deur beide gewasse het verskil tussen klein en groot sakke, wat aangedui
het dat verskillende sakgroottes verskillende besproeiingsbestuur strategieë vereis. Skedulering tot
die hoogste voorafbepaalde onttrekkingsvlak het, in vergelyking met die waterryke behandelings,
besproeiing verminder met 124 L m-2 in die klein en 240 L m-2 in die groot sakke vir komkommers,
en 427 L m-2 in die klein en 487 L m-2 in die groot sakke vir tamatie plante. Opbrengste van
kweekhuis tamatie plante in die groot plantsakke en komkommer plante in die klein en groot sakke
is gehandhaaf of verbeter deur skedulering tot die hoogste onttrekkingsvlak (ongeveer 60% van
beskikbare water inhoud), in vergelyking met die waterryke behandeling. Die kombinasie van
verminderde besproeiing en verbeterde of gehandhaafde opbrengste het gelei tot verbeterde
watergebruiksdoeltreffendheid (besproeiing en transpirasie) vir die hoogste onttrekkingsvlak, in
vergelyking met die waterryke behandelings. In al die glashuis eksperimente het die waterryke
behandeling gelei tot oorvloedige watergebruik deur plante.
’n Finale studie is uitgevoer om gewas waterstremming van kweekhuis komkommer en tamatie
plante wat onderwerp is aan oorvloedige watervoorsiening deur agt keer per dag te besproei en
sikliese watertekorttoestande, te vergelyk. Die vergelyking is gebaseer op die transpirasie
verhouding en opbrengs, terwyl die gebruik van kapasitansie sensors vir besproeiingskedulering in
kokosveen vir beide gewasse geëvalueer is. Transpirasie data het aangedui dat komkommer en
tamatie plante wat onderwerp is aan oorvloedige watervoorsiening vroeër waterstremming ervaar as
plante wat onderwerp is aan sikliese watertekorttoestande, ongeag van die sakgrootte. Resultate het
aangedui dat besproeiingskedulering volgens wateronttrekkingsvlakke vir klein sakke nog nie
aanbeveel kan word vir kweekhuis tamatie en komkommer plante alvorens verdere navorsing
gedoen is nie. Skedulering tot wateronttrekkingsvlakke vir groot sakke word egter geregverdig deur
die verbeterde of gehandhaafde opbrengste van kweekhuis komkommers en tamaties. Die beraamde
laagste onttrekkingsvlakke vir groot sakke wat nie opbrengs betekenisvol sal beïnvloed nie is 85%
vir tamaties en 70% vir komkommers.
Ten slotte dui die resultate duidelik daarop dat die gebruik van kapasitansie sensors in groot
plantsakke besproeiingsbestuur van hidroponiese komkommers en tamaties in kokosveen verbeter
deur oorbesproeiing uit te skakel en die watergebruiksdoeltreffendheid te verbeter. Meer navorsing
is nodig alvorens ’n gevolgtrekking gemaak kan word ten opsigte van besproeiingskedulering met
kapasitansie sensors in klein plantsakke.
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Effects of soil amendments on crusting, seedling emergence and yield of onion, tomatoes and peppers.Yacoub, Mohamed Mohamed. January 1991 (has links)
The effects of sulfur-containing amendments (H₂SO₄,Al₂(SO₄)₃ and gypsum) or crust formation, soil chemical properties, seedling emergence and yields of onions (Allium cepa), tomatoes (Lycopersicum esculentum) and chili peppers (Capsicum sp.) were studied on a Pima clay loam soil. Treatments were surface applied on a strip above the seeds. The chemicals influenced the penetrometer index, soil-pH, electrical conductivity, DPTA-extractable soil Fe, Cu, Zn, Mu and seedling emergence in two greenhouse experiments. Gypsum and H₂SO₄ increased seedling emergence while Al₂(SO₄)₃ reduced the soil-pH and EC more than H₂SO₄ and gypsum. Based upon penetrometer readings, H₂SO₄ was the best anti-crusting agent tested followed by gypsum and Al₂(SO₄)₃. At the end of the study, all soil samples were very low in KCl extractable Al, showing that Al toxicity was not responsible for seedling damage. Gypsum decreased levels of Mn and Zn but did not affect Fe and Cu. Al₂(SO₄)₃ increased Fe and Zn, decreased Cu but did not affect Mn. H₂SO₄ did not affect extractable Mn, Cu, Zn and Fe levels. In a field study using two water qualities at Safford, gypsum produced the most tomato seedlings whereas Al₂(SO₄)₃ and H₂SO₄ produced the least. Onion stand counts were not affected by the chemicals with either water. Gypsum, H₂SO₄ and Al₂(SO₄)₃ polymer produced the highest pepper stand counts with the saltier water but there were no differences with lower salt water. Tomatoes produced the highest yield with gypsum and lowest with H₂SO₄ and Al₂(SO₄)₃ with saltier water. With lower salt water, gypsum produced highest yield, followed by the H₂SO₄. Both H₂SO₄ treatments produce low yields. Onions showed no treatment response under lower salt water, while with saltier water, gypsum and H₂SO₄ produced the highest yields. Pepper yields were not affected by amendments with the lower salt water. Al₂(SO₄)₃ polymer, H₂SO₄ and gypsum increased yields with the saltier water. Varieties of peppers and tomatoes produced different yields in response to water quality in a supplementary field study.
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Characterization, Simulation, Analysis and Management of Hydraulic Properties of Greenhouse Plant Growth SubstratesChen Lopez, Jose Choc January 2011 (has links)
The greenhouse industry is facing significant challenges such as the demand for more efficient use of energy and natural resources and prevention of detrimental environmental impacts. Reducing negative environmental impacts can be achieved by utilizing recycled and environmentally friendly products and by optimizing the use of water and root zone substrates. New and advanced root zone substrates are currently tested as substitute for natural soils in greenhouse agriculture. They can be inert non-organic materials such as rockwool and perlite. These are mined products from the earth, and are difficult to dispose after use. Natural substrates such as peat are being consumed faster than being regenerated. A new potential substrate that consists of recycled foamed glass aggregates is considered an alternative, as it is environmentally friendly, non-toxic and disposable. Experiments with foamed glass aggregates and with foamed glass aggregate/coconut coir mixtures indicated that the yield of greenhouse tomatoes was not statistically significant different (α=0.05) when compared to rockwool. To investigate the potential application of recycled glass as a root zone substrate, physical and hydraulic properties were measured. For comparison, the same measurements were completed for rockwool, coconut coir, perlite, and PET/PE fibers as well as for a mixture of coconut coir and recycled glass. The water characteristics (WC) determined for each substrate exhibited distinct air entry potentials, which provided information for irrigation scheduling, water storage and aeration for optimum plant growth conditions. Coconut coir and rockwool exhibited a unimodal shaped water retention curve, while foamed glass aggregates and perlite exhibited bimodal shaped curves. The obtained substrate properties were used as input paramaters for HYDRUS- 2D/3D model to simulate water mass balance and matric potential distributions within a typical growth container of foamed glass aggregates. The simulated matric potential and water content distributions were compared to tensiometer measurements of matric potential in the foamed glass aggregates. The simulations compared favorably with laboratory experiments measured under controlled environmental conditions.
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Effect of post-harvest treatment on ripening and quality of tomato fruit using ozone : application of different ozone doses as controlled atmosphere storage for delay ripening and maintaining the quality of tomatoes and effect of ozone on antioxidant and sugar compounds at different stages of tomato fruit ripeningShalluf, Milad A. January 2010 (has links)
Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars. Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study.
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Participação de ácido jasmônico nas respostas do tomateiro ao sombreamento por plantas daninhas /Orzari, Izabela. January 2018 (has links)
Orientador: Pedro Luis da Costa Aguiar Alves / Coorientador: Rogério Falleiros Carvalho / Banca: Priscila Lupino Gratão / Banca: Tiago Pereira Salgado / Banca: Mariluce Pascoina Nepomuceno / Resumo: As plantas emitem sinais a fim de acionar respostas de defesa ao estresse sofrido pela baixa radiação solar (sombreamento), que pode ser causado pela presença de outras plantas. O fitormônio ácido jasmônico (AJ) pode fazer parte das respostas das plantas ao sombreamento. Os objetivos deste trabalho foram avaliar a participação do AJ nas respostas do tomateiro (Solanum lycopersicum L.), híbrido Heinz 9553, ao sombreamento artificial e à competição com a planta daninha Raphanus raphanistrum L. O primeiro experimento foi realizado em duas épocas do ano (outono-inverno e primavera-verão). O tomateiro foi cultivado sob sombreamento artificial (sombrite) e luz natural (ambiente sem cobertura), e aplicou-se metil-jasmonato (MeJA - 0; 0,15; 0,25 e 0,50 mM) e ibuprofeno (IBU - 0; 1,25; 2,5 e 5,0 mM) aos 7, 14, 21 e 28 dias após o transplante das mudas. Observou-se que a condição luminosa teve maior efeito nas respostas apresentadas pelas plantas do que o MeJA e o IBU, independente da concentração aplicada. Os efeitos nas análises bioquímicas foram mais pronunciados, mas não houve diferenças nas análises de crescimento. O segundo experimento consistiu em manter o tomateiro H9553 sob sombreamento promovido pela planta daninha R. raphanistrum L. (nabiça). Estudou-se a competição sob diferentes densidades da planta daninha (0, 11, 16 e 22 plantas m-2), sendo aplicado o MeJA (0,50 mM) no tomateiro. Os resultados mostraram que em condições de alto nível de sombreamento, o aumento da quantid... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Plants emit signals in order to trigger defense responses to the stress of low solar radiation (shading), which may be caused by the presence of other plants. Jasmonic acid phormonium (JA) may be part of the plants responses to shading. The aims of this work were to evaluate the participation of JA in tomato responses (Solanum lycopersicum L.), Heinz 9553 hybrid, to artificial shading and competition with the weed Raphanus raphanistrum L. The first experiment was carried out at two seasons of the year (autumn-winter and spring-summer). Tomatos were cultivated under artificial shading (sombrite) and natural light (uncovered environment), and methyl jasmonate (MeJA: 0, 0.15, 0.25 and 0.50 mM) and ibuprofen (IBU: 0, 1.25, 2.5 and 5.0 mM) were applied at 7, 14, 21 and 28 days after transplanting the seedlings. It was observed that the light condition had greater effect on the responses presented by the plants than the MeJA and the IBU, regardless of the applied concentration. The effects on biochemical analyzes were more pronounced, but there were no differences in growth analyzes. The second experiment consisted in keeping tomato H9553 under shading promoted by the weed R. raphanistrum L. (radish). Competition was studied under different densities of R. raphanistrum (0, 11, 16 and 22 plants m-2), and the MeJA (0.50 mM) was applied to the tomato. The results showed that in conditions of high shading, increasing the amount of JA did not interfere in the development of the plants and did not affect productivity, but the greatest effect on the crop was due to the low luminosity. Thus, in general, it can be concluded that the accumulation of JA is involved with conditions of low R:FR ratio, such as shading, but its effects on the plant due to this condition are not accentuated. However, further studies need to be performed on non-model plants to further assess JA participation in shaded plants. / Doutor
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An investigation of tomato curly stunt virus in South AfricaFali, Azola Kuhle 31 October 2006 (has links)
Student Number : 0314429G -
MSc research report -
School of Molecular and Cell Biology -
Faculty of Science / Tomato (Lycopersicon esculentum) is a horticultural commodity of great
economic importance in many parts of the world, including South Africa. A
previous study identified a new begomovirus, Tomato curly stunt virus (ToCSV),
as the causative virus of a new and potentially devastating disease of tomatoes in
South Africa. In this study, symptomatic plants, suspected of infection with an
uncharacterized ToCSV isolate (01/2521) were collected for screening from
Pietermaritzburg, South Africa. A host range study was conducted with the
original ToCSV isolate (99/0631). Two small DNA molecules (1449 nts and 755
nts) were found associated with ToCSV [01/2521] using near-full length primers
AL1c2745 and PAR1v32 specific for ToCSV. A single small DNA molecule (842
nts) was also found in association with the original ToCSV isolate. Nucleotide
sequence analysis revealed that the two small DNA molecules (1449bp and
755bp) have no significant nucleotide sequence identity (less than 20%) with any
known begomovirus. The 842bp molecule has the most significant nucleotide
sequence identity (48%) to that of ToCSV (AF261885), while less than 20%
nucleotide sequence identities were found when compared with other
begomoviruses. Nucleotide sequence alignment of the 842bp DNA molecule to
the ToCSV sequence, showed that this small DNA molecule is a chimeric
molecule that could have arisen through recombination, partly from the coding
regions of the ToCSV genome, but the rest of the molecule is of unknown origin.
All three small DNA molecules identified in this study were compared to some
known begomovirus associated subgenomic molecules and satellite molecules,
and sequence identities of less than 20% were found. To our knowledge, this is the
first report of a small DNA molecule found associated with the ToCSV genome.
The complete genome sequence of ToCSV [01/2521] was not determined. Based
on the results we obtained from the host range study, all the chosen test plants are
not susceptible to ToCSV infection. The infectivity of all the small molecules
identified in this study, is currently being investigated.
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Tomate seco obtido por energia solar e convencional a partir de mini-tomates congelados / Dried tomatoes produced by solar and conventional energy from mini-tomatoes frozenAlessi, Egly Sturion 18 October 2010 (has links)
O tomate constitui-se uma das hortaliças mais exploradas cientificamente, devido à sua importância comercial. O tomate pode, através de processamento adequado, dar origem a inúmeros produtos, alguns deles de elevado consumo no Brasil. Depois da boa aceitação do tomate cereja pelo consumidor, um novo segmento de mini-tomate, chamado Grape, começa a despontar nos mercados brasileiros. O destaque é o híbrido Sweet Grape, que está agradando ao gosto do consumidor e animando agricultores que aderiram às experiências com a nova cultivar. Seu teor de sólidos solúveis chega a 10 °Brix e tem menos acidez, comparado a outras variedades, as quais contem entre 4 e 5 °Brix. Nesse trabalho foi avaliado o processo produtivo do tomate seco, a partir de mini-tomates sweet grape, congelados desidratados em secador solar e convencional, visando obter um alimento seguro do ponto de vista microbiológico, físico-quimica, instrumental cor e aceitabilidade) Os tomates cereja tipo Sweet Grape, foram secos até teores de umidade entre 35% e 0%, e observadas suas mudanças em relação aos tomates in natura , e seu comportamento nos períodos de armazenamento após processados de 0, 30, 60 e 90 dias, verificando assim a sua estabilidade. Foi ainda caracterizado o fruto in natura e submetido a um précongelamento para uma previa perda de água facilitando a secagem. A avaliação da qualidade do produto foi realizada através das análises microbiológicas, físico-químicas, composição centesimal e sensorial. Houve diferença significativa entre os secadores, elétrico e solar, para todos os parâmetros analisados, porém não houve alteração significativa para o período de armazenamento. Em relação à avaliação sensorial, o tomate seco ao sol obteve melhor aceitação entre os provadores / The tomato is one of the vegetables are more scientifically investigated, due to its commercial importance. The tomato can, through appropriate processing, giving rise to numerous products, some of high consumption in Brazil. After the good acceptance by consumers of cherry tomatoes, a new segment of mini-tomato, called Grape, begins to emerge in the Brazilian markets. The highlight is the hybrid Sweet Grape, which is pleasing to the taste of consumers and encouraging farmers adhered to experiment with new cultivars. Your soluble solids content reaches 10 ° Brix and has less acidity compared to other varieties, which contain between 4 and 5 ° Brix. In this study we evaluated the production process of dried tomato, from mini-sweet grape tomatoes, frozen and dehydrated in conventional solar dryer was used to obtain a food safe from microbiological point of view,. physico-chemical, instrumental color and acceptability) Cherry Tomatoes Sweet Grape type, have been dried to moisture contents between 35% and 50%, and observed their changes for tomatoes in nature, and their behavior during periods of storage after processed 0, 30, 60 and 90 days, thus confirming its stability. It was further characterized the fresh fruit and undergo a pre-freeze to a predicted loss of water facilitating drying. Assessing the quality of the product was carried out by microbiological, physicochemical, chemical composition and sensory. There were significant differences between the dryers, electric and solar, for all parameters analyzed, but no significant change for the period of storage. Regarding the sensory evaluation, the sun-dried tomatoes the best won acceptance among judges
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Atividade anti-inflamatória de extrato fenólico de tomate roxo (Solanum Lycopersicum L.) em camundongo em modelo de peritonite induzido pelo LPS / Anti-inflammatory activity of phenolic extract of purple tomato (Solanum lycopersicum L.) in mouse model of peritonitis induced by LPS.Maia, Afonso Pinho da Silva 11 March 2015 (has links)
Visando a produção de um alimento que possua elevados teores de compostos bioativos, a piramidação de genes é uma técnica capaz de estimular o acúmulo e a expressão de novas classes de flavonoides em tecidos vegetais, como por exemplo, o tomate roxo, rico em antocianinas. As antocianinas podem atenuar o processo inflamatório através da modulação da cascata de sinalização e da expressão de enzimas, sendo este um dos possíveis mecanismos de ação que leva a promoção da saúde, atribuído a esta classe de compostos. Assim, o objetivo deste trabalho foi avaliar a ação anti-inflamatória do extrato de tomate roxo, obtido por piramidação dos genes Anthocyanin Fruit (Aft), Aubergine (Abg) e atroviolaceum (atv), em camundongos submetidos ao modelo de peritonite induzida por lipopolissacarídeo (LPS). O fruto tomate vermelho - Micro Tom (MT) e o transformado foram caracterizados quanto ao seu perfil de compostos fenólicos. A casca do tomate roxo, rica em antocianinas, apresentou conteúdo de fenólicos totais dez vezes maior quando comparado à casca do MT, apresentando também maiores quantidades de ácido ascórbico e capacidade antioxidante avaliado nos métodos DPPH e ORAC; em relação à polpa e casca do tomate vermelho e a polpa do tomate roxo. Os principais flavonoides identificados na casca do tomate roxo, por CLAE-DAD, foram: as antocianidinas petunidina (86,5 mg/100 g b.u.), delfinidina (6,85 mg/100 g b.u.), principalmente na forma acilada, e o flavonol rutina (106,26 mg/100 g b.u.). A propriedade anti-inflamatória dos compostos fenólicos foi avaliada através de um modelo de peritonite, em camundongos, induzida por LPS. O extrato aquoso do tomate roxo, rico em antocianinas (2 e 4 mg petunidina eq./100 g peso corpóreo) foi administrado, por via oral, 30 minutos antes do estímulo inflamatório. No exsudato peritoneal, coletado após 3h do estímulo, foi observada, no grupo que recebeu 4 mg quando comparado ao grupo estimulado com LPS, uma redução significativa (p<0,05) de cerca de 37% no número de leucócitos totais e de 64% na expressão gênica de mRNA de COX-2 e na produção de citocinas pró-inflamatórias (TNF-α, IL-1β, IL-2, IL-6 e MCP-1), assim como um aumento significativo da citocina anti-inflamatória IL-10. Em estudo de absorção, os metabólitos: delfinidina aglicona (m/z 303) e malvidina aglicona (m/z 331) foram detectados, por cromatografia líquida ESI-MS/MS, nas amostras de fígado dos animais eutanasiados após 30 minutos de administração do extrato do tomate roxo. Portanto, os resultados demonstram que as antocianinas presentes no tomate roxo, por meio dos metabólitos encontrados no fígado dos animais, apresentam atividade anti-inflamatória através do controle do influxo leucocitário, da modulação da expressão gênica de COX-2 e da produção citocinas. / Aiming to produce a food having high contents of bioactive compounds, the gene pyramiding is a technique capable of stimulating the expression and accumulation of new classes of flavonoids in plant tissues, such as purple tomato, rich in anthocyanins. Anthocyanins may attenuate the inflammatory process by modulating the signaling cascade and expression of enzymes, which is one of the possible mechanisms of action that leads to health promotion, assigned to this class of compounds. The objective of this study was to evaluate the anti-inflammatory action of the purple tomato paste, obtained by pyramiding of genes Fruit Anthocyanin (Aft), Aubergine (Abg) and atroviolaceum (atv) in mice submitted to peritonitis model induced by lipopolysaccharide (LPS). The tomato fruit - Micro Tom (MT) and the transformed were characterized according to their profile of phenolic compounds. The purple tomato peel, rich in anthocyanins, phenolics content presented ten times higher compared to the shell of the MT, and also provides increased amounts of ascorbic acid and antioxidant activity in the DPPH rated and the ORAC methods; than the pulp and peel the tomato pulp and purple tomatoes. The main flavonoids identified in tomato peel purple, by HPLC-DAD were: petunidin the anthocyanidins (86.5 mg / 100 g wb), delphinidin (6.85 mg / 100 g wb), especially in the acylated form, and flavonol rutin (106.26 mg / 100 g bu). The anti-inflammatory properties of the phenolic compounds was evaluated through a model of peritonitis in mice induced by LPS. The extract of purple tomato, rich in anthocyanins (2 and 4 petunidin mg eq. / 100 g body weight) was administered orally 30 minutes before the inflammatory stimulus. In the peritoneal exudate collected after 3 h of stimulation was observed in the group receiving 4 mg as compared to the LPS stimulated group, a significant reduction (p <0.05) of about 37% in the number of total leukocytes and 64 % mRNA gene expression of COX-2 and production of proinflammatory cytokines (TNF-α, IL-1β, IL-2, IL-6 and MCP-1), as well as a significant increase of the anti-inflammatory cytokine IL-10. In a study of absorption, the metabolites: aglycone delphinidin (m / z 303) and malvidin aglycone (m / z 331) were detected by HPLC - ESI-MS / MS, in liver samples from animals euthanized 30 minutes after administration the purple tomato extract. Therefore, the results show that anthocyanins present in the purple tomato, through the metabolites found in animal liver, exhibit anti-inflammatory activity by controlling the leukocyte influx, the modulation of gene expression of COX-2 and production cytokines.
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Cloning and analysis of promoter regulating the expression of a purple acid phosphatase.January 2001 (has links)
Zhang Siyi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 97-109). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / List of Tables --- p.vii / List of Figures --- p.viii / List of Abbreviations --- p.x / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.3 / Chapter 2.1 --- Phosphorus and higher plants --- p.3 / Chapter 2.1.1 --- Phosphorus is a macronutrient in higher plants --- p.3 / Chapter 2.1.2 --- The forms of phosphorus in plant cells --- p.3 / Chapter 2.1.3 --- Phosphorus compartments and pools in plant cells --- p.6 / Chapter 2.2 --- The acquisition of phosphorus in higher plants --- p.8 / Chapter 2.2.1 --- The forms of phosphorus absorbed by higher plants --- p.8 / Chapter 2.2.2 --- Soil phosphorus bioavailability --- p.9 / Chapter 2.2.3 --- Uptake and transportation of phosphorus --- p.10 / Chapter 2.3 --- Adaptive responses of higher plants to phosphorus deficiency --- p.11 / Chapter 2.3.1 --- Phosphorus homeostasis --- p.12 / Chapter 2.3.2 --- Enhancement of phosphorus uptake --- p.14 / Chapter 2.3.3 --- Phosphorus scavenging and recycling --- p.16 / Chapter 2.4 --- Regulation of gene expression under phosphorus starvation --- p.18 / Chapter 2.5 --- Acid phosphatase and purple acid phosphatase in plants --- p.22 / Chapter 2.5.1 --- Acid phosphatases --- p.22 / Chapter 2.5.2 --- Purple acid phosphatase (PAP) --- p.26 / Chapter Chapter 3: --- Hypothesis --- p.31 / Chapter Chapter 4: --- Materials and Methods --- p.33 / Chapter 4.1 --- Materials --- p.33 / Chapter 4.1.1 --- Chemicals --- p.33 / Chapter 4.1.2 --- Plant materials --- p.33 / Chapter 4.1.3 --- Plasmid vectors and bacterial strains --- p.33 / Chapter 4.1.4 --- DNA sequencing --- p.34 / Chapter 4.1.5 --- Softwares: --- p.34 / Chapter 4.2 --- Methods: --- p.35 / Chapter 4.2.1 --- Survey of PAP occurrence in higher plants --- p.35 / Chapter 4.2.2 --- Determination of multi-gene family and gene copy number of PAPin tomato genome --- p.40 / Chapter 4.2.3 --- Effect of environmental Pi on the morphology of tomato and APase induction --- p.43 / Chapter 4.2.4 --- PAP expression in tomato seedlings growing at different Pi concentrations --- p.46 / Chapter 4.2.5 --- Genomic library construction and PAP promoter isolation --- p.48 / Chapter 4.2.6 --- PAP promoter activity assay by transient expression of reporter gene..… --- p.52 / Chapter Chapter 5: --- Results --- p.56 / Chapter 5.1 --- Identification of PAP gene in higher plants --- p.56 / Chapter 5.1.1 --- Design of primers and total RNA extraction --- p.56 / Chapter 5.1.2 --- RT-PCR --- p.57 / Chapter 5.1.3 --- Further investigation of PAP homologous sequences in monocotyledons --- p.60 / Chapter 5.2 --- Determination of multi-gene family and gene copy number of tomato PAP gene (TPAP 1) --- p.62 / Chapter 5.2.1 --- Determination of TPAP 1 copy number --- p.62 / Chapter 5.2.2 --- Determination of tomato PAP multi-gene family --- p.63 / Chapter 5.3 --- Effect of environmental phosphorus on the morphology of tomato seedling and APase induction --- p.66 / Chapter 5.3.1 --- Morphological changes of tomato seedlings under phosphorus starvation --- p.66 / Chapter 5.3.2 --- Acid phosphatase assays --- p.72 / Chapter 5.4 --- The phosphorus-regulated expression of tomato PAP --- Northern blot analysis --- p.74 / Chapter 5.5 --- Genomic library construction and PAP promoter isolation --- p.76 / Chapter 5.6 --- PAP promoter sequence --- p.79 / Chapter 5.7 --- Promoter activity assay through transient expression of reporter gene --- p.84 / Chapter 5.7.1 --- Effect of untranslation region of PAP gene --- p.84 / Chapter 5.7.2 --- Assay of PAP promoter activities regulated by phosphorus --- p.85 / Chapter Chapter 6: --- Discussion --- p.88 / Chapter 6.1 --- The wide occurrence and high conservation of plant PAP --- p.88 / Chapter 6.2 --- Tomato as a model plant and the organization of PAP gene in genome --- p.89 / Chapter 6.3 --- Morphological changes of tomato under phosphorus starvation and the induction of APase --- p.90 / Chapter 6.4 --- Regulation of PAP in tomato --- p.92 / Chapter 6.5 --- Isolation of PAP promoter --- p.92 / Chapter 6.6 --- Assay of PAP promoter activity --- p.93 / Chapter 6.7 --- Future perspectives --- p.94 / Chapter Chapter 7: --- Conclusion --- p.95 / References --- p.97
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