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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.
211

The role of arbuscular mycorrhizal fungi in sustainable tomato production.

Martin, Ashley William January 2007 (has links)
The work in this thesis aimed to demonstrate the contribution of arbuscular mycorrhizal (AM) fungi to the yield and fruit quality of field-grown processing tomatoes, and the potential to increase the sustainability of tomato production through greater fertiliser use efficiency by inoculating tomato seedlings with beneficial AM fungi. Previously, the conclusion that tomato growth is unresponsive to AM colonisation, particularly in high-P soils, has often been based on only a part of the tomato life-cycle. However, there is increasing evidence that that positive AM yield responses can occur in soils with relatively high plant-available P, and that AM responsiveness of tomato during vegetative growth may be a poor predictor of reproductive growth. A preceding industry study found that AM colonisation of field-grown processing tomatoes was very low, mostly less than 5%. The reason for the low colonisation was unclear since previous studies have shown that tomato can become relatively highly colonised by AM fungi. It was not known if farm practices, such as soil cultivation and chemical sterilisation, which have been shown to decrease AM colonisation of tomato and other crops, could have contributed to the low colonisation. Furthermore, it was unclear what contribution AM fungi were making to the yield and fruit quality of tomato in commercial production, and what their potential contribution might be if greater AM colonisation could be achieved through inoculating seedlings. Yield and fruit quality are important to tomato growers as both are used to calculate payment when the fruits are sold. Large amounts of soluble fertilisers, particularly P, are applied during tomato production with the aim of increasing yield and quality. However, fertiliser use efficiency, particularly P, on tomato farms has been identified as being low, and needing to be improved in order to increase the economic and environmental sustainability of tomato farming. Increasing P, and also other nutrients, such as Zn and Ca, in tomatoes could also help to improve agricultural sustainability by alleviating human malnutrition in developing countries and, in the case of Ca, have the potential to reduce blossom end rot, which can severely reduce marketable yield. There is considerable potential for AM fungi to assist in the supply of these nutrients to field-grown tomatoes. AM fungi are widely accepted to increase plant uptake of P. This has mostly been demonstrated in low-P soils, as increases in plant-available P are generally known to be detrimental to AM colonisation and any subsequent growth effects. However, there is increasing evidence of the ability of AM fungi to increase P uptake and yield even in high P soils. There is also good evidence of increased Zn uptake by mycorrhizal supply to plants. Evidence for increased Ca uptake in mycorrhizal plants is in comparison limited and conflicting, but has been demonstrated in some cases. It is possible that AM fungi could allow applications of these nutrients, particularly P, to be reduced while maintaining or increasing fruit yield and quality. However, the ability of indigenous or inoculated AM fungi to do so in the relatively high-P farm soils used in this project was unknown. In order to address these uncertainties a series of pot studies and a field experiment were conducted using field soils from tomato farms and an adjacent nature reserve for comparison. Data on soil characteristics from five farms, collected during the previous industry study, was analysed in conjunction with data from another farm located nearby with contrasting soil properties. Two farm soils and an unfarmed comparison were selected on the basis of their having contrasting levels of P, Zn and Ca, and pH, with the constraint that they were located within 50 km of each other to minimise travel time in the study area. The two farmed soils had a relatively high concentration of plant-available P (103 and 58 mg/kg Colwell), while plant-available P in the unfarmed soil was probably marginal to that required for healthy tomato growth (27 mg/kg Colwell). Samples of the soils were taken soon after commencement of the work and used in pot studies. Firstly, a bioassay was conducted to establish the ability of tomato to become colonised in the three field soils. AM colonisation of tomato and medic, which is known to be highly susceptible to AM colonisation, was compared between three harvests over an approx. 16 week period. Vegetative growth was also measured. The total colonisation of tomato mostly did not differ from that of medic at each harvest in any soil. Furthermore, despite the large differences in plant-available P between the three soils, colonisation and vegetative growth of tomato did not differ between soils at any harvest. In a subsequent pot experiment, the effect of colonisation by AM fungi in the three field soils on the vegetative and reproductive growth, and nutrient status of tomato was determined using the tomato mutant rmc (reduced mycorrhizal colonisation) and its progenitor 76R. A number of non-destructive vegetative and reproductive growth measurements were repeatedly measured over an approx. 24 week period. Destructive measurements were carried out at two harvests, 39 and 164 days after planting. Tomato 76R was again well colonised in all soils. Tomato rmc remained uncolonised, and was therefore an effective non-mycorrhizal control. AM colonisation had little effect on plant growth or nutrient status in any soil at the first harvest, but significant growth and nutrient responses were recorded at the second harvest. In particular, AM colonisation markedly increased vegetative growth in the unfarmed soil. AM colonisation did not affect vegetative growth in either of the farmed soils. However, AM colonisation increased reproductive growth, particularly yield over time, in all soils. AM colonisation increased shoot P concentration and content, but effects on Zn were mixed and largely inconclusive. Shoot Ca concentration and content were mostly reduced by AM colonisation. Similar patterns were observed in fruit nutrient status. The potential of pre-inoculation with AM fungi to increase AM colonisation and/or AM growth and nutrient effects in the field was considered. A commercial AM fungal inoculum was initially proposed for use, but was found to be unreliable and laboratory cultures of Scutellospora calospora and Glomus mosseae were used instead. Tomato seedlings were inoculated by amending a commercial seed-raising medium with an equal mixture of S. calospora and G. mosseae inocula. Seeds of tomato rmc, 76R and the commercial processing tomato cultivar U941 were sown and raised according to the practices followed by a commercial seedling nursery. After 9 weeks a sub-sample of inoculated seedlings of 76R and U941 had become colonised by both AM fungi, although the total colonisation was relatively low (approx. 10%). There was no difference in the shoot or root dry weights between inoculated and non-inoculated seedlings. The remaining seedlings were then used in the field experiment. Seedlings were transplanted amongst a commercial processing tomato crop on two farms and grown to maturity. A substitute farm with soil of moderate P (66 mg/kg Colwell) was used as tomatoes were no longer being grown on the initial farm with moderate P. Two P treatments, ‘normal’ and ‘reduced’ P fertilisation, were imposed in order to investigate the effect of P fertilisation on colonisation by indigenous and inoculated AM fungi, and growth and nutrient status of tomato in the field. Non-destructive growth measurements and soil core samples to assess mycorrhizal colonisation were taken mid-season (approx. 10 weeks after transplanting). Destructive growth measurements and core samples to assess colonisation were taken at harvest (approx. 19 weeks after transplanting). Colonisation of rmc was insubstantial and it again served as an effective non-mycorrhizal control to 76R. Colonisation was insubstantial in all treatments on the farm where soil had moderate plant-available P. On the other farm, where soil had relatively high plant-available P, colonisation of all plants was low mid-season, but was mostly substantial (>20%) in 76R and U941 at harvest. Low colonisation on both farms was probably the result of farming practices, particularly soil cultivation. However, a combination of inoculation and reduced P fertilisation increased colonisation. Colonisation by indigenous AM fungi had no effect on the growth or nutrient status of field grown tomatoes. In contrast, pre-inoculation with AM fungi increased fruit yield by a mean of approx. 40% in 76R and U941. This was the result of an 18% increase in the fresh weight of individual fruits and, when inoculation was combined with reduced P fertilisation, a 21% increase in the number of fruits on each plant. The increase in the number of fruits on each plant was associated with an increase in the number of flowers at the most advanced growth stage. Inoculation also increased vegetative growth, and fruit P, Zn and Ca contents. A small (4%) decrease in fruit brix was more than offset by increased yield. This study has shown that while AM fungi indigenous to tomato farm soils have the ability to substantially colonise tomato, they appear to have little effect on tomato growth, yield or nutrition in the field. In contrast, inoculation of tomato seedlings with mutualistic AM fungi during nursery production can substantially increase the growth, yield and fruit nutrient contents of field-grown tomatoes under commercial conditions. This increase could also be enhanced by a reduction in P fertilisation. Increased yield and fruit nutrient contents, and decreased P fertilisation neatly address the aims of increased agricultural sustainability. Incorporating pre-inoculation of tomato into existing farming practices has a potential to increase the productivity and sustainability of processing tomato production worldwide. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292847 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007
212

Analyse des variations de poids et de teneurs en sucres du fruit de tomate par une approche intégrative combinant des études écophysiologique, génétique et moléculaire

Prudent, Marion 19 March 2009 (has links) (PDF)
Le poids et la teneur en sucres du fruit sont deux caractères complexes, importants pour la qualité de la tomate. L'objectif de cette thèse est de disséquer ces deux caractères par une démarche pluridisciplinaire, impliquant des approches écophysiologiques, génétiques et moléculaires. Une population de 20 lignées d'introgression de Solanum chmielewskii dans le fonds génétique de S. lycopersicum a été cultivée en 2006 et en 2007 sous deux conditions de charges en fruits afin de moduler sa disponibilité en carbone : une forte charge où tous les fruits sont conservés sur les bouquets, et une faible charge constituée par un unique fruit par bouquet. Des indicateurs de processus écophysiologiques impliqués dans le poids et la teneur en sucres du fruit ont été mesurés ou estimés. Ils ont permis de caractériser les principaux processus écophysiologiques sous-jacents aux QTL de qualité, notamment la division et l'expansion cellulaire, la transpiration du fruit, et l'allocation carbonée pour la synthèse de composés structuraux. Un fort effet de la charge en fruits a été mis en évidence sur l'expression des QTL pour la plupart des caractères observés, indiquant l'occurrence d'interactions génotype x charge en fruits. L'utilisation d'un modèle écophysiologique prédisant la teneur en sucres d'un fruit de tomate à maturité, combiné à une détection de QTL, a permis d'identifier des colocalisations entre QTL de qualité et QTL de variables de fonctionnement du fruit telles que la fourniture du fruit en assimilats, la transformation métabolique des sucres en d'autres composés, ou la dilution des composés par l'entrée d'eau dans le fruit. Enfin, une lignée d'introgression portant des QTL de poids frais et de sucres avec des allèles aux effets opposés ainsi que la lignée conférant le fonds génétique ont été étudiées au niveau moléculaire par une analyse du transcriptome en phase d'expansion cellulaire. Des gènes candidats dont le niveau d'expression serait associé aux variations de poids et de teneurs en sucres du fruit, engendrées par une modification de la charge en fruits ont été identifiés. L'analyse en cinétique de l'expression de quelques gènes candidats a permis de mettre en évidence des liens entre variables écophysiologiques et moléculaires.
213

DEFENCE GENE EXPRESSION IN THE TOMATO-VERTICILLIUM PATHOSYSTEM

Castroverde, Christian Danve 22 April 2010 (has links)
In tomato (Solanum lycopersicum), race-specific resistance against the fungal wilt pathogen Verticillium dahliae race 1 (Vd1) is established in the stem. However, the molecular factors and mechanisms leading to this resistance response are still unknown. In this study, Craigella resistant (CR) and susceptible (CS) tomato plants were successfully infected with Vd1 and this was verified by fungal quantification and symptom score assays. Previous microarray results showed interesting patterns of defence gene expression that correlated with biological phenomena. Plant defence genes code for proteins that are responsible for or associated with the plant resistance response. Through RT-PCR, this thesis set out to confirm these microarray observations and also to generate expression data for genes in which sensitivity was an issue in the microarray. The standard RT-PCR data confirmed a number of the microarray results, but some conflicts remained. From the defence genes investigated, there was agreement between the microarray data and the RT-PCR data for pre-mRNA processing factor 8, class IV chitinase, cyclin-dependent kinase inhibitor and IMP dehydrogenase/GMP reductase. Partial agreement was observed for genes coding for ethylene response factor 2, phenylalanine ammonia lyase and P6 protein. However, there was total disagreement for 14-3-3, beta-glucanase, P1a, RNA-binding protein, calcium-binding protein and S-Adenosyl-L-methionine: hydroxide adenosyltransferase. Real-time RT-PCR was attempted to clarify the remaining issues but further discrepancies arose, particularly in the Ve resistance genes. To resolve these discrepancies, two approaches were designed: (1) one based on the use of a universal internal control and (2) another based on restriction enzyme digestion. In general, the results were more consistent with standard RT-PCR. Overall, this study showed that standardization of a system involving vascular pathogens, leading to reproducible analysis, was possible but only with proper controls and additional validation. Standard RT-PCR appeared to offer a more accurate picture of the expression of defence genes in the tomato-Verticillium pathosystem. The defence gene expression results confirmed in this study remain as potential insights into the molecular mechanisms for Verticillium resistance in tomato plants.
214

Irrigação subsuperficial deficitária no cultivo de tomateiro em casa de vegetação

Mendonça, Thaís Grandizoli 17 April 2017 (has links)
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:29Z No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:36Z (GMT) No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:43Z (GMT) No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Made available in DSpace on 2017-08-16T20:20:49Z (GMT). No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) Previous issue date: 2017-04-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The tomato is a demanding crop in regards to water and is among the most consumed vegetables in Brazil. The search for alternatives to improve tomato productivity, as well as reduce the water use in the crop cycle, is essential for agricultural production and environment. The objectives of this work were to evaluate the contribution of subsurface drip irrigation to yield and fruit quality of Grape tomatoes and to estimate the water use efficiency (EUA). The experiment was carried out in the CCA / UFSCar and consisted of three treatments with four randomized blocks. Irrigation management considered the storage soil water capacity (CAD), the soil moisture being high according to the water content reference of the treatment, 0.33 (T1), 0.29 (T2) and 0.25 m3 m-3 (T3), corresponding to 100 % replacement of CAD, and deficit irrigations of 75 and 50 % of CAD, respectively. Water content was monitored by TDR probes and the roots depth obtained through a root images scanner. The Grape tomatoes were transplanted under drip lines installed at 0.20 m depth. Quantitative and qualitative characteristics of the fruits were evaluated in relation to the proposed treatments, being: fruits number per plant, average fruit mass and productivity, quantitative characteristics and; Diameter, length, soluble solids, fruit pH and dry mass of leaves and stem, qualitative characteristics. The total water applied was 1297 mm in T1, 471 mm in T2 (36 % of water applied in T1) and 234 mm in T3 (18 % of T1). Among the characteristics evaluated, the T2 did not differ from the T1 treatment, except in the diameter and pH. The T3 treatment was equal to T1 only in the fruits number per plant. The average fruit mass was different among all treatments and there was no difference between soluble solids values. The T3 treatment obtained higher EUA, followed by T2 and T1, but did not have higher productivity nor better results in other evaluated attributes. Deficit subsurface irrigation of 75 % of CAD did not interfere in Grape tomato productivity and fruit quality, being the most recommended because of qualitative and quantitative attributes similar to full irrigation and to increase the EUA. It is concluded that deficit subsurface irrigation had productivity and fruit quality of Grape tomatoes like full irrigation when used 75 % of CAD, increased the water use efficiency and contributed with water use reduction in crop cycle. / O tomateiro é uma cultura exigente em água e está entre as hortaliças mais consumidas no Brasil. A busca por alternativas que melhorem sua produtividade, bem como reduzam o uso da água no ciclo da cultura, é essencial para a produção agrícola e para o meio ambiente. Este trabalho teve o objetivo avaliar a contribuição da irrigação subsuperficial deficitária na produtividade e qualidade dos frutos de tomateiros Grape e estimar a eficiência no uso da água (EUA). O experimento foi realizado no CCA/UFSCar e consistiu de três tratamentos com doze parcelas em blocos casualizados. O manejo da irrigação levou em consideração a capacidade de água disponível no solo (CAD), sendo a umidade do solo elevada de acordo com a umidade de referência do tratamento, 0,33 (T1), 0,29 (T2) e 0,25 m3 m-3 (T3), correspondendo à reposição de 100 % da CAD, e irrigações deficitárias de 75 e 50 % da CAD, respectivamente. A umidade do solo foi monitorada por sondas TDR e o crescimento das raízes por imagens obtidas através de scanner de raízes. As mudas de tomateiro Grape foram transplantadas sob linhas de gotejamento instaladas a 0,20 m de profundidade. Foram avaliados atributos quantitativos e qualitativos dos frutos em relação aos tratamentos propostos, sendo eles: número de frutos por planta, massa média dos frutos e produtividade como atributos quantitativos; diâmetro, comprimento, sólidos solúveis, pH dos frutos e massa seca das folhas e caule como atributos qualitativos. A lâmina total de água aplicada foi 1297 mm em T1, 471 mm em T2 (36 % da lâmina aplicada em T1) e 234 mm em T3 (18 % de T1). Entre os atributos avaliados, o diâmetro e pH dos frutos do tratamento T2 diferiram do T1. Já o tratamento T3 foi igual ao T1 apenas no número de frutos por planta. A massa média dos frutos foi diferente entre todos os tratamentos e não houve diferença no valor de sólidos solúveis. O tratamento T3 obteve maior EUA, seguido por T2 e T1, porém não teve maior produtividade e nem melhores resultados em outros atributos avaliados. A irrigação subsuperficial deficitária de 75 % da CAD não interferiu na produtividade do tomateiro Grape e na qualidade dos frutos, sendo a mais recomendada por apresentar atributos qualitativos e quantitativos similares à irrigação plena e aumentar a EUA. Conclui-se com este trabalho que irrigação subsuperficial deficitária teve produtividade e qualidade de frutos de tomateiro Grape semelhante à irrigação plena quando utilizado 75 % da CAD, aumentou a eficiência no uso da água e contribuiu com a redução no uso da água no ciclo da cultura.
215

Hormetic UV treatments for control of plant diseases on protected edible crops

Scott, George January 2017 (has links)
Hormesis is a dose response phenomenon where low doses of a stress bring about a positive response in the organism undergoing treatment. UV-C hormesis has been known for over three decades and has a broad range of benefits on postharvest produce. Benefits include increased nutritional content, delayed chlorophyll degradation and disease resistance. The beneficial effects have been observed on many varieties of fresh produce including climacteric and non-climacteric fruit, tubers, salads and brassicas. The majority of previous studies have used low-intensity (LIUV) UV-C sources. LIUV sources require lengthy treatment times, which are in the region of 6 minutes for tomato fruit. This has, in part, prevented the commercial application of this technique. High-intensity, pulsed polychromatic light (HIPPL) sources, however, have recently been developed. HIPPL sources may have the potential to drastically reduce treatment times and increase their commercial viability. It was shown, here, that the use of HIPPL can control disease (reduce disease progression) caused by Botrytis cinerea and Penicillium expansum and also delay ripening on tomato fruit. Both disease control and delayed ripening were at similar levels for LIUV and HIPPL treatments on mature green fruit. The HIPPL treatments used in these studies can reduce treatment times for tomato fruit by 97.3%. Both HIPPL and LIUV treatments elicit local responses irrespective of the treatment orientation and tomato fruit, therefore, require full surface irradiation. Furthermore, UV-C in the HIPPL source is not required for disease control or delayed ripening. It does, however, contribute approximately 50% towards the total observed effects. Investigations into the mechanisms underpinning postharvest HIPPL and LIUV hormesis, on tomato fruit, identified that the expression of genes involved in plant hormone biosynthesis, defence, secondary metabolism and ripening were affected. This indicates that disease control is achieved through induced resistance. Changes to expression, following treatment, were highly similar for both HIPPL and LIUV treatments and were mediated by salicylic acid, jasmonic acid and ethylene. This may lead to broad range resistance against necrotrophic and biotrophic pathogens as well as abiotic stresses and herbivorous pests. Recently, the exposure of foliage to UV-C has been shown to induce resistance against B. cinerea on Arabidopsis thaliana. The horticultural applications of such treatments, however, have not been explored. Pre-harvest treatments of lettuce in the glasshouse showed variation in damage threshold and optimal treatment to control disease following LIUV and HIPPL treatment. Further sources of variation included the cultivar, pathogen of interest and the point that treatment was applied during the year. Using a controlled environment allowed seasonal variation to be mitigated and both HIPPL and LIUV treatments controlled disease against B. cinerea. For pre-harvest treatments to be a success in the glasshouse, further studies into how both biotic and abiotic factors influence treatment is required. To circumvent the problems associated with pre-harvest treatments and environmental variation in the glasshouse, LIUV seed treatments were performed on tomato. Control of B. cinerea was established with an approximately 10% reduction in incidence and disease progression with a 4 kJ/m2 treatment. When monitoring the effect of treatment on germination and early seedling development it was also identified that an 8 kJ/m2 treatment led to biostimulation of germination and root and shoot growth.
216

Uso de paclobutrazol na produção de mudas, no crescimento, produção e qualidade de frutos de tomateiro em ambiente protegido

Seleguini, Alexsander [UNESP] 05 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-05Bitstream added on 2014-06-13T19:24:51Z : No. of bitstreams: 1 seleguini_a_dr_ilha.pdf: 1010511 bytes, checksum: eb32bdc0873ccf57c670095c19e87ff7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente trabalho foi avaliar os efeitos de três concentrações (0, 50 e 100 mg L-1) e dois métodos de aplicação (embebição de sementes e rega de plântulas) de paclobutrazol (PBZ) na produção de mudas, no desenvolvimento e produção de plantas, bem como na qualidade físico-química e vida de prateleira de frutos de tomateiro, híbrido longa vida AF 7631. O trabalho foi conduzido na Universidade Estadual Paulista (UNESP), campus de Ilha Solteira, Estado de São Paulo, Brasil, de setembro de 2006 a março de 2007. As embebições de sementes com 50 e 100 mg L-1 de PBZ inibiram e atrasaram a emergência de plântulas, mas foram ineficientes na redução da altura das plântulas. Entretanto, a aplicação do regulador, via rega, nas mesmas concentrações, aos 15 dias após a semeadura, controlou o desenvolvimento da parte aérea, como demonstrado pelos menores valores médios de altura, área foliar e massa de matéria seca de parte aérea das plântulas, determinando, ainda, o aumento do diâmetro da haste e do desenvolvimento do sistema radicular das plântulas. Após o transplantio das mudas em ambiente protegido, observou-se que os métodos de aplicação e o incremento das concentrações de PBZ não influenciaram significativamente a produtividade. O tratamento das mudas via rega, com concentrações crescentes de PBZ, reduziu linearmente a altura das plantas, a taxa de crescimento absoluto, a altura de inserção da primeira inflorescência e a massa de matéria seca de folhas e hastes. Independentemente do método de aplicação de PBZ, o aumento das concentrações reduziu significativamente o vigor das brotações laterais e aumentou a produção de frutos pequenos. Ainda, as regas das mudas com 50 e 100 mg L-1 de PBZ, aos 15 dias após a semeadura, não alteraram a vida de prateleira dos frutos, porém, com o aumento... / The aim of the present work was to evaluate the effects of three solution concentrations (0, 50, 100 mg L-1) and two methods of application (seed imbibition and drench of seedlings) of paclobutrazol (PBZ), on seedlings production, plant development and yield, as well as physico-chemical quality and shelf-life of tomato fruits, hybrid AF 7631. The experiment was conducted out at São Paulo State University, UNESP, campus of Ilha Solteira, São Paulo State, Brazil, from September of 2006 to March of 2007. It was found that the seeds imbibitions with PBZ, at 50 and 100 mg L-1, inhibited or delayed the seedlings emergence, as well as it was ineffective in reducing the height of the seedlings. However, the use of growth regulator drenches, in the same concentrations, at the 15th day after the sowing, was effective in controlling the plant development, as showed by the lowest means of seedlings height, leaf area and dry mass, and it still contributed to the increase in the stem diameter, measured at the base of the hypocotyls, and in the development of seedlings roots of tomatoes. After the seedlings transplant to the greenhouse, it was observed that the methods of application, as well as plant growth regulator concentration, did not affected significantly the yield. The seedling drenches, with increasing PBZ concentrations, induced linear decrease in the plant height, in the absolute growth rate, in the height of the first inflorescence and in the dry matter mass of leaves, shoots and stem. It was also observed that, independently of the method of application, the increase in PBZ solution concentrations significantly reduced the side shoots vigour and increased the yield of fruits classifield as small size. Further more, the drenches of PBZ on tomato seedlings, in concentrations of 50 and 100 mg L-1, did not ...(Complete abstract click electronic access below)
217

Uso de paclobutrazol na produção de mudas, no crescimento, produção e qualidade de frutos de tomateiro em ambiente protegido /

Seleguini, Alexsander. January 2007 (has links)
Orientador: Max José de Araújo Faria Júnior / Banca: Shizuo Seno / Banca: Jacira dos Santos Isepon / Banca: Arlete Marchi Tavares de Melo / Banca: Marie Yamamoto Reghim / Resumo: O objetivo do presente trabalho foi avaliar os efeitos de três concentrações (0, 50 e 100 mg L-1) e dois métodos de aplicação (embebição de sementes e rega de plântulas) de paclobutrazol (PBZ) na produção de mudas, no desenvolvimento e produção de plantas, bem como na qualidade físico-química e vida de prateleira de frutos de tomateiro, híbrido longa vida AF 7631. O trabalho foi conduzido na Universidade Estadual Paulista (UNESP), campus de Ilha Solteira, Estado de São Paulo, Brasil, de setembro de 2006 a março de 2007. As embebições de sementes com 50 e 100 mg L-1 de PBZ inibiram e atrasaram a emergência de plântulas, mas foram ineficientes na redução da altura das plântulas. Entretanto, a aplicação do regulador, via rega, nas mesmas concentrações, aos 15 dias após a semeadura, controlou o desenvolvimento da parte aérea, como demonstrado pelos menores valores médios de altura, área foliar e massa de matéria seca de parte aérea das plântulas, determinando, ainda, o aumento do diâmetro da haste e do desenvolvimento do sistema radicular das plântulas. Após o transplantio das mudas em ambiente protegido, observou-se que os métodos de aplicação e o incremento das concentrações de PBZ não influenciaram significativamente a produtividade. O tratamento das mudas via rega, com concentrações crescentes de PBZ, reduziu linearmente a altura das plantas, a taxa de crescimento absoluto, a altura de inserção da primeira inflorescência e a massa de matéria seca de folhas e hastes. Independentemente do método de aplicação de PBZ, o aumento das concentrações reduziu significativamente o vigor das brotações laterais e aumentou a produção de frutos pequenos. Ainda, as regas das mudas com 50 e 100 mg L-1 de PBZ, aos 15 dias após a semeadura, não alteraram a vida de prateleira dos frutos, porém, com o aumento...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the present work was to evaluate the effects of three solution concentrations (0, 50, 100 mg L-1) and two methods of application (seed imbibition and drench of seedlings) of paclobutrazol (PBZ), on seedlings production, plant development and yield, as well as physico-chemical quality and shelf-life of tomato fruits, hybrid AF 7631. The experiment was conducted out at São Paulo State University, UNESP, campus of Ilha Solteira, São Paulo State, Brazil, from September of 2006 to March of 2007. It was found that the seeds imbibitions with PBZ, at 50 and 100 mg L-1, inhibited or delayed the seedlings emergence, as well as it was ineffective in reducing the height of the seedlings. However, the use of growth regulator drenches, in the same concentrations, at the 15th day after the sowing, was effective in controlling the plant development, as showed by the lowest means of seedlings height, leaf area and dry mass, and it still contributed to the increase in the stem diameter, measured at the base of the hypocotyls, and in the development of seedlings roots of tomatoes. After the seedlings transplant to the greenhouse, it was observed that the methods of application, as well as plant growth regulator concentration, did not affected significantly the yield. The seedling drenches, with increasing PBZ concentrations, induced linear decrease in the plant height, in the absolute growth rate, in the height of the first inflorescence and in the dry matter mass of leaves, shoots and stem. It was also observed that, independently of the method of application, the increase in PBZ solution concentrations significantly reduced the side shoots vigour and increased the yield of fruits classifield as small size. Further more, the drenches of PBZ on tomato seedlings, in concentrations of 50 and 100 mg L-1, did not ...(Complete abstract click electronic access below) / Doutor
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Caracteriza??o fenot?pica de plantas transg?nicas de tomateiro expressando a prote?na reprimida por auxina (SIARP)

Estevam, Renata Kaline Souza 27 May 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-27T13:32:41Z No. of bitstreams: 1 RenataKalineSouzaEstevam_TESE.pdf: 2591439 bytes, checksum: 8a5092689ed7b6122d0702466b33f854 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-31T13:43:08Z (GMT) No. of bitstreams: 1 RenataKalineSouzaEstevam_TESE.pdf: 2591439 bytes, checksum: 8a5092689ed7b6122d0702466b33f854 (MD5) / Made available in DSpace on 2017-01-31T13:43:08Z (GMT). No. of bitstreams: 1 RenataKalineSouzaEstevam_TESE.pdf: 2591439 bytes, checksum: 8a5092689ed7b6122d0702466b33f854 (MD5) Previous issue date: 2016-05-27 / A flora??o ? um processo vital durante o ciclo de vida das plantas e ? marcado pela convers?o do meristema apical vegetativo em reprodutivo devido a intera??es de fatores internos e externos ? planta. Apesar de amplo conhecimento ter sido gerado nessa ?rea, ainda se conhece muito pouco sobre o processo de flora??o e frutifica??o em tomateiro. Pesquisas anteriores realizadas pelo nosso grupo identificaram o cDNA hom?logo a Prote?na Reprimida por Auxina (ARP) em bibliotecas subtrativas reprodutivas de tomateiro. Existem poucos dados sobre a prote?na ARP na literatura, h? relatos de que o gene ARP est? relacionado com a matura??o do fruto em morango, dorm?ncia da gema lateral em ervilha e matura??o do p?len em tabaco, mas a fun??o da prote?na ARP ainda n?o est? clara. Portanto, o intuito deste trabalho foi compreender o papel da prote?na ARP no desenvolvimento vegetativo e nos processos de flora??o e frutifica??o por meio da perda e/ou do ganho de fun??o deste cDNA em plantas transg?nicas de tomateiro contendo o cassete de superexpress?o em orienta??o senso e antissenso para este cDNA. Dessa forma, foram observadas algumas altera??es fenot?picas e estruturais nas plantas transg?nicas (35S::SlARP antissenso e senso), como flora??o e frutifica??o precoce verificada nas plantas 35S::SlARP antissenso nas gera??es T1 a T4, em rela??o ?s controles (transformada com o plasm?deo vazio e n?o transformada). Na an?lise histol?gica, notaram-se ?vulos maduros nas flores das plantas 35S::SlARP antissenso (gera??es T2 a T4), enquanto que as flores das controles n?o apresentaram ?vulos maduros no mesmo per?odo de tempo. Outra modifica??o observada foi o n?mero superior de gemas laterais desenvolvidas nas plantas 35S::SlARP antissenso nas gera??es T3 e T4 quando comparado ?s plantas 35S::SlARP senso e ?s plantas controles (transformada com o plasm?deo vazio e n?o transformada) . Essas produziram ramos com folhas, flores e frutos. Assim como altera??es estruturais nos pec?olos das plantas 35S::SlARP antissenso, incluindo uma aparente quantidade maior de elementos de vaso (xilema e floema) do que os pec?olos as plantas 35S::SlARP senso e mutantes relacionados ? sinaliza??o da auxina (dgt e entire) e plantas controles. Portanto, estes dados sugerem que a prote?na ARP possa estar envolvida na flora??o, frutifica??o e na dorm?ncia das gemas axilares em tomateiro. / Flowering is a vital process during the plant life cycle and it is characterized by the conversion from the vegetative apical meristem into reproductive meristem due to internal and external factors. Despite the considerable knowledge has been produced in this field, not much is known about the flowering and fruiting process in tomato. Furthermore, previous research from our group has identified a cDNA with homology to AUXIN REPRESSED PROTEIN (ARP) in reproductive subtractive libraries from tomato. In the literature, there are few reports where the ARP gene has been associated to fruit ripening in strawberry, dormancy in pea and pollen maturation in tobacco plants, but it is not clear the ARP protein function yet. Therefore, the aim of this work was to understand the role of ARP protein in vegetative development, flowering and fruit set processes through the loss and/or gain of function using this cDNA in transgenic tomato plants with the overexpression cassette constructs in sense and antisense cDNA orientation. Thus, it was observed some phenotypic and structural modifications in transgenic plants (35S::SlARP antisense and sense) such as early flowering and fruiting that was observed in 35S::SlARP antisense plants from the T1 to T4 progeny when compared to controls plants (with the empty vector and wild type plant). In the histological analysis, it was observed mature ovule in 35S::SlARP antisense flowers (progeny T2 to T4), while for the controls plant it wasn?t observed a mature ovule at the same period of time. The other modification observed was a higher number of lateral buds developed in 35S::SlARP antisense plants (progeny T3 and T4) when compared to 35S::SlARP sense and controls plants. These plants produced branches with leaves, flowers and fruits. Besides, it has been observed some structural changes in the petioles from 35S::SlARP antisense plants, including a high number of vessel elements (xylem and phloem) when compared to 35S::SlARP sense, and to dgt and entire mutants (related to auxin signaling) and controls plants (with empty vector and wild type plant). Therefore, these data suggest that ARP protein may be involved in flowering, fruit set and dormancy of axillary buds in tomato.
219

Srovnání biolistické a agrobakteriem zprostředkované transgenoze rajčete (Solanum lycopersicum L.) / The comparison of biolistic and Agrobacterium mediated transformation of tomato (Solanum lycopersicum L.)

DĚDOUCHOVÁ, Martina January 2008 (has links)
Currently we can do genetic manipulation by means of direct and indirect methods. Indirect methods use strategy of gram-negative soil bacteria Agrobacterium tumefaciens, which introduces part of its own genes carried by the section of plasmid Ti called T-DNA into the genome of infected plants. It is difficult to reach the transformation of monocotyledonous plants using this method. Application of direct methods of transformation offers the possibility for transformation of monocotyledonous plants. One of the most effective methods of direct transformation is biolistic transformation. This diploma thesis dealt with the comparison of efficacy of biolistic and A. tumefaciens mediated transformation of tomato (Solanum lycopersicum L.).
220

Evapotranspiração e coeficiente de cultura do tomateiro industrial estimado por sensoriamento utilizando o algoritmo SAFER / Evapotranspiration and crop coefficient of tomato by sensor using algorithm SAFER

Sales, Déborah Lídya Alves 02 March 2016 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-06-02T17:11:39Z No. of bitstreams: 2 Dissertação - Déborah Lídya Alves Sales - 2016.pdf: 2080595 bytes, checksum: 8e8ea7a4a6459b955d318cfa8219c08a (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-03T12:18:31Z (GMT) No. of bitstreams: 2 Dissertação - Déborah Lídya Alves Sales - 2016.pdf: 2080595 bytes, checksum: 8e8ea7a4a6459b955d318cfa8219c08a (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-03T12:18:31Z (GMT). No. of bitstreams: 2 Dissertação - Déborah Lídya Alves Sales - 2016.pdf: 2080595 bytes, checksum: 8e8ea7a4a6459b955d318cfa8219c08a (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2016-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The production of industrial tomato has stood out in the Brazilian agribusiness scenario. In the Cerrado region, production occurs in the dry season (May to October), in large irrigated areas, mainly by central pivot (irrigation system accounts for about 90% of the industrial tomato production area). Although the production is considered hi-tech, the sector is still very lacking in technical and scientific information to assist the crop reaches potential productivity and quality in the region. Proof of this is the low average yield obtained (80 t/ha) compared to major producing regions in the world (Spain, United States, mainly), which feature double that productivity. One of the required information is the water requirement of tomato hybrids on local growing conditions. The refinement of this information can contribute to a better design of irrigation projects, as well as better water management throughout the cycle, and the better management of water resources. However, traditional methods of research, in this area, require the use of evapotranspirometers, which are expensive and require occasional and data acquisition systems, which complicates their use. More, remote sensing techniques have been applied effectively, already tested in other regions and have been quite promising. This study aimed to estimate the current crop evapotranspiration (ET) two tomato hybrid for industrial processing, N901 and H1308, and their respective crop coefficients (Kc) by the energy balance model SAFER (Simple Algorithm for Evapotranspiration Retrieving) is using images from Landsat 8 OLI / TIRS in orbit 221/72 and 222/71, and compared to traditional micrometeorological method using reference evapotranspiration (ETo Penman-Monteith), with Kcs recommended by FAO 56 and Embrapa. The study was conducted at Fazenda head of Piracanjuba in the municipality of Silvânia-GO, in the period from May to August 2015, in clay soil with conventional tillage. In addition, the leaf water potential (weekly) and the water content in the soil water balance by the dynamic site was monitored. The water potential in leaf and soil moisture show that no water deficit throughout the 122-day cycle. The results showed also that the culture accumulated total evapotranspiration of 351.97, 340.97 and 356.24 mm, by FAO 56, EMBRAPA and SAFER methods, respectively. The Kcs estimated by SAFER method showed a significant correlation with the methods FAO 56 and Embrapa (FAO 56, R ² = 0.98; Embrapa, R² = 0.95).A ETa estimated by SAFER method showed a significant correlation with micrometeorological methods (FAO 56, R2 = 0.97 and EMBRAPA, R2 = 0.97). Therefore, Safer can be used to estimate the tomato ETa in the Cerrado region. / A produção de tomate industrial vem se destacando no cenário agroindustrial brasileiro. Na região do Cerrado, a produção ocorre no período seco do ano (maio a outubro), em grandes áreas irrigadas, principalmente por pivô central (sistema de irrigação responsável por cerca de 90% da área de produção de tomate industrial). Apesar da produção ser considerada tecnificada, o setor ainda é muito carente de informações técnico-científicas que auxiliem a cultura atingir o potencial de produtividade e qualidade na região. A prova disso é a baixa produtividade média atual (80 t/ha) em comparação a importantes regiões produtoras no mundo (Espanha e Estados Unidos, principalmente), que apresentam o dobro desta produtividade. Uma das informações fundamentais é a necessidade hídrica dos híbridos de tomateiro nas condições locais de cultivo. O refinamento desta informação pode auxiliar no melhor dimensionamento de projetos de irrigação, assim como no melhor manejo da água ao longo do ciclo, e pela melhor gestão dos recursos hídricos. Entretanto, os métodos tradicionais de pesquisa nesta área requerem o uso de evapotranspirômetros que são onerosos e pontuais e necessitam de sistemas de aquisição de dados, o que dificulta sua utilização. Mas, técnicas de sensoriamento remoto vêm sendo aplicadas com eficiência, já testadas em outras regiões e tem se mostrado bem promissoras. Assim, este estudo teve o objetivo de estimar a evapotranspiração atual da cultura (ETa) de dois híbridos de tomateiro para o processamento industrial, N901 e H1308, e os seus respectivos coeficientes de cultura (Kc) pelo modelo de balanço de energia SAFER (Simple Algorithm for Evapotranspiration Retrieving) utilizando imagens do satélite Landsat 8 OLI/TIRS, na órbita 221/72 e 222/71, e comparação com tradicional método micrometeorológico utilizando evapotranspiração de referência (ETo Penman-Monteith), com os Kcs recomendados pela FAO 56 e EMBRAPA. O estudo foi realizado na Fazenda cabeceira do Piracanjuba, no município de Silvânia-GO, no período de maio a agosto de 2015, em solo argiloso com preparo convencional. Além disso, foi monitorado o potencial de água na folha (semanalmente) e o conteúdo de água no solo pelo balanço hídrico dinâmico local. O potencial de água na folha e a umidade do solo revelaram que não ocorreu déficit hídrico ao longo do ciclo de 122 dias. Os resultados mostraram, ainda, que a cultura acumulou uma evapotranspiração total de 351,97, 340,97 e 356,26 mm pelos métodos FAO 56, EMBRAPA e SAFER, respectivamente. Os Kcs estimado pelo método do SAFER apresentou significante correlação com os métodos FAO 56 e Embrapa (FAO 56, R² = 0,98; Embrapa, R² = 0,95). A ETa estimada pelo método do SAFER apresentou significante correlação com os métodos micrometeorológicos (FAO 56, R2 = 0,97; Embrapa, R2 = 0,97), podendo este ser utilizado para estimativa da ETa do tomateiro na região.

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