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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.
581

Effects of haulm killing and gibberellic acid on seed potato (<em>Solanum tuberosum L.</em>) and techniques for micro- and minituber production in northern latitudes

Virtanen, E. (Elina) 06 May 2014 (has links)
Abstract Seed potato is the starting point in the potato (Solanum tuberosum L.) production chain. In order to secure potato production in a variety of production conditions, plant diseases must be controlled and the yield characteristics of the used cultivars ensured. In addition, production must be cost-effective. Characteristics particular to northern production conditions include long periods of daylight and a short growing season as well as a several months long seed potato storage period. The focus of the present study is on northern production conditions and methods, including haulm killing and sprout control, which are presumed to affect seed potato quality, as well as the initial stages of the seed potato production chain, i.e. micro- and minituber production, which could influence cost-effectiveness and propagation. Haulm killing is one of the methods used in seed potato production to regulate tuber size. It is often carried out on unsenesced plants. The present results, however, indicate that cultivar properties have a greater effect on the sprouting and crop yield of seed potatoes than production-phase haulm killing or temperature sum accumulation. Nevertheless, haulm killing carried out three weeks after flowering (75 DAP) accelerated emergence. When the effect of haulm killing methods on seed potatoes was compared with natural haulm senescence, haulm killing was shown to increase disease pressure. Black scurf (Rhizoctonia Solani) was present in seed tubers whose haulm had been destroyed by mechanical or mechanical-chemical haulm killing. Naturally senesced haulm had less black scurf, and crop quantity and starch content developed to a level typical of the cultivar. Storage periods lasting several months make controlling seed potato sprouting more challenging. Therefore, use of the plant hormone gibberellic acid (GA) in sprout control was investigated. GA treatments at lower concentration (100 mM) increased the number of tubers in the cultivar Fambo. Thus, the timing of haulm killing and in the case of Fambo, GA treatment influenced the characteristics of seed potatoes. Conventionally, the first tuber generation is produced using microplants to produce minitubers in greenhouses. This production method is, however, labour-intensive, and energy and investment costs are high. With the aim of increasing production efficiency in northern production conditions, the production of minitubers in the laboratory using a novel bioreactor technology and in growth rooms using the hydroponic technique was investigated. The Liquid LabTM Rocker bioreactor system was used in vitro, all the cultivars examined (Asterix, Timo, Van Gogh and Velox) produced microtubers. The quantity of tubers produced per dish varied between 30 (for the cultivar Asterix in eight weeks) and 75 (for the cultivar Velox in 11 weeks). The results showed hydroponic production of minitubers to be successful in indoor conditions: the cultivars Desiree and Van Gogh developed their first tuber three weeks faster than Asterix, and the minituber yield was 4.5 per plant for Desiree, 7.5 for Van Gogh and 4.0 for Asterix. When the results indicate that both the Liquid LabTM Rocker production method and the hydroponic production method are suitable for mass production of seed potatoes. / Tiivistelmä Siemenperuna on lähtökohta perunan (Solanum tuberosum L.) tuotantoketjussa. Jotta perunantuotanto turvataan eri tuotanto-olosuhteissa, on hallittava siemenperunan kasvitaudit, taattava sadontuotto-ominaisuudet ja tuotannon on oltava lisäksi kustannustehokasta. Pohjoisissa tuotanto-olosuhteissa erityispiirteinä ovat valoisuudeltaan pitkät päivät ja kestoltaan lyhyet kasvukaudet. Lisäksi siemenperunoiden varastointijakso kestää useita kuukausia. Tässä tutkimuksessa selvitettiin vaikuttavatko pohjoiset tuotanto-olosuhteet tai tuotannossa käytetyt varsistonhävitys tai itämisen hallinta siemenperunoiden laatuominaisuuksiin. Lisäksi selvitettiin siemenperunoiden ensimmäisen mukulasukupolven (mikro- ja minimukula) tuotantoa eri tekniikoilla. Siemenperunatuotannossa varsistonhävitystä käytetään mukulakoon säätelykeinona. Varsistonhävitys tehdään usein tuleentumattomaan kasvustoon. Saatujen tulosten perusteella lajikeominaisuudet vaikuttivat itämiseen ja sadontuotto-ominaisuuksiin enemmän kuin varsistonhävitys tai mukuloihin kerääntynyt lämpösumma. Varsistonhävitys kolme viikkoa kukinnasta (75 päivää istutuksen jälkeen) nopeutti kuitenkin siemenperunoiden taimettumista. Vertailtaessa varsistonhävitysmenetelmien vaikutusta siemenperunaan verranteena kasvuston luontainen tuleentuminen, varsistonhävitys lisäsi kasvitautipainetta. Mekaanis-kemiallisesti ja mekaanisesti varsistonhävityissä satomukuloissa tuli esiin seittirupea (Rhizoctonia solani). Luontaisesti tuleentuneen kasvuston sadoissa oli seittirupea vähemmän ja myös sadon määrä ja tärkkelyspitoisuus kehittyivät lajikkeelle luontaiselle tasolle. Useiden kuukausien varastointijakso vaikeuttaa siemenperunoiden itämisen hallintaa. Kun tutkittiin gibberelliinihapon (GA) käyttöä itämisen hallintaan, alhaisemman konsentraation (100mM) GA –käsittely lisäsi Fambo –lajikkeen mukulalukumäärää. Tulosten perusteella varsistonhävityksen ajoittamisella ja GA –käsittelyllä (Fambo –lajike) vaikutettiin siemenperunoiden ominaisuuksiin. Siemenperunan ensimmäisen mukulasukupolven eli minimukuloiden tuottaminen tapahtuu perinteisesti kasvihuonekasvatuksena mikrokasveista. Tuotantotapa on työvoima-, energia- ja invetointikustannuksia vaativaa. Tuotannon tehostamiseksi pohjoisissa tuotanto-olosuhteissa tutkittiin mikro- ja minimukuloiden tuotantoa eri teknologioilla. Mikromukuloita tuotettiin bioreaktorimenetelmällä laboratoriossa ja minimukuloita hydroponisella menetelmällä kasvatushuoneissa. Tulokset osoittavat, että kaikki tutkitut lajikkeet (Asterix, Timo, Van Gogh ja Velox) tuottivat bioreaktorissa mikromukuloita. Mikromukuloiden määrä vaihteli 30:sta (Asterix, 8 viikon kasvatus) 75:een (Velox, 11 viikon kasvatus). Myös minimukuloiden hydroponinen tuotanto sisätiloissa on mahdollista; kaikki lajikkeet muodostivat mukuloita, Desiree ja Van Gogh 3 viikkoa nopeammin kuin Asterix. Desiree tuotti minimukuloita 4.5 kpl/kasvi, Van Gogh 7.5 ja Asterix 4.0. Tulokset osoittavat, että molemmat menetelmät (bioreaktori ja hydroponinen) soveltuvat mikro- ja minimukuloiden massatuotantoon.
582

A predictive biogeography of selected alien plant invaders in South Africa

Youthed, Jennifer Gay January 1997 (has links)
Five techniques were used to predict the potential biogeography of the four alien plant species, Acacia longifolia, Acacia mearnsii, Opuntia ficus-indica and Solanum sisymbrifolium. Prediction was based on five environmental factors, median annual rainfall, co-efficient of variation for rainfall, mean monthly maximum temperature for January, mean monthly minimum temperature for July and elevation. A geographical information system was used to manage the data and produce the predictive maps. The models were constructed with presence and absence data and then validated by means of an independent data set and chisquared tests. Of the five models used, three (the range, principal components analysis and discriminant function analysis) were linear while the other two (artificial neural networks and fuzzy logic) were non-linear. The two non-linear techniques were chosen as a plant's response to its environment is commonly assumed to be non-linear. However, these two techniques did not offer significant advantages over the linear methods. The principal components analysis was particularly useful in ascertaining the variables that were important in determining the distribution of each species. Artifacts on the predictive maps were also proved useful for this purpose. The techniques that produced the most statistically accurate validation results were the artificial neural networks (77% correct median prediction rate) and the discriminant function analysis (71% correct median prediction rate) while the techniques that performed the worst were the range and the fuzzy classification. The artificial neural network, discriminant function analysis and principal component analysis techniques all show great potential as predictive distribution models.
583

Response of potato to paclobutrazol and manipulation of reproductive growth under tropical conditions

Tsegaw, Tekalign 08 February 2006 (has links)
High temperature limit successful potato cultivation in the lowlands of tropical regions. One effect of high temperature may be an increase in gibberellin activity that is inhibitory to tuberization. Paclobutrazol blocks gibberellin biosynthesis and reduces its level in the plant. The effect of paclobutrazol on potato was examined under non-inductive conditions in a greenhouse and under field conditions in the hot tropical lowlands of eastern Ethiopia. Paclobutrazol was applied as a foliar spray or soil drench at rates equivalent to 0, 2, 3, and 4 kg a. i. per ha. Paclobutrazol increased chlorophyll a and b content, and photosynthetic efficiency, enhanced early tuber initiation, delayed physiological maturity, and increased tuber fresh mass, dry matter content, specific gravity and crude protein content. It reduced the number of tubers per plant and extended the tuber dormancy period. Paclobutrazol reduced shoot growth, and plant height, and increased the partitioning of assimilates to the tubers while reducing assimilate supply to the leaves, stems, roots and stolons. Stomatal conductance and the rate of transpiration were reduced. In addition, paclobutrazol treatment increased tuber N, Ca and Fe content while reducing P, K and Mg content. Growth analyses indicated that paclobutrazol decreased leaf area index, crop growth rate, and total biomass production. It increased specific leaf weight, tuber growth rate, net assimilation rate, and partitioning coefficient (harvest index). Microscopic observations showed that leaves of treated plants developed thicker epicuticular wax layers. The epidermal, palisade and spongy mesophyll cells were larger. It increased the thickness of the cortex and the size of vascular bundles and pith cells of the stem. It also increased the width of the cortex and favoured the formation of more secondary xylem vessels, resulting in thicker roots. Deposition of starch grains in the stem pith cells, and cortical cells of the stem and root, were stimulated in response to paclobutrazol treatment. In most instances the method of application did not affect the efficiency of paclobutrazol. The effect of cultivar and reproductive growth on growth, photosynthetic efficiency, water relations, dry matter production, tuber yield and quality of potato was also the subject of investigation. Non-flowering, flowering and fruiting plants of cultivars Al-624, Al-436, CIP-388453-3(A) and CIP-388453-3(B) were evaluated under field conditions of a sub-humid tropical highland of eastern Ethiopia. Cultivars exhibited differences with respect to leaf stomatal conductance, rate of transpiration, net photosynthesis, biomass production and allocation, tuber yield, tuber size distribution, specific gravity, dry matter content and nutrient composition. Fruiting plants had higher leaf stomatal conductance, and higher rates of transpiration and photosynthesis rates. The leaf area index, tuber growth rate, and partitioning coefficient (harvest index) of the fruiting plants were reduced, but crop growth rates and net assimilation rates were higher. Without affecting total dry matter production, fruit development reduced the amount partitioned to the leaves, stems, roots, and tubers. Fruit development reduced total and marketable tuber mass and tuber numbers. The effect of MCPA and paclobutrazol were studied under greenhouse and field conditions. Single foliar sprays were applied during the early and full bud development stages at rates of 0, 250, 500, and 750 g a.i. ha-1. Both MCPA and paclobutrazol greatly reduced the number of flowers and completely inhibited berry set. MCPA did not affect the number, yield, dry matter content and specific gravity of tubers. Without affecting the number of tubers, paclobutrazol increased tuber yield, dry matter content and specific gravity. / Thesis (DPhil (Horticultural Science))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted
584

Germinação e crescimento inicial de três espécies pioneiras do bioma cerrado no Distrito Federal, Brasil / Germination and initial growth of three pioneer species of Cerrado Bioma in the Federal District, Brazil

Martins, Rosana de Carvalho Cristo 30 July 2004 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-01-12T10:57:12Z No. of bitstreams: 1 texto completo.pdf: 1369974 bytes, checksum: 9fd8ea4315b0b8b8c2670673f4f5c850 (MD5) / Made available in DSpace on 2017-01-12T10:57:12Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1369974 bytes, checksum: 9fd8ea4315b0b8b8c2670673f4f5c850 (MD5) Previous issue date: 2004-07-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As espécies Sclerolobium paniculatum Vogel var. subvelutinum Benth. e Solanum lycocarpum A. St.-Hil. são típicas do Cerrado sensu stricto que sobressaem em áreas degradadas por desmatamentos e pelo fogo, enquanto a espécie Cecropia pachystachya Trécul se destaca em Matas de Galeria perturbadas pela formação de clareiras; ambas as espécies apresentam comportamento pioneiro. Este trabalho visou verificar o pioneirismo em espécies de Cerrado sensu stricto e de Matas de Galeria do Bioma Cerrado, através da análise da germinação e do crescimento inicial dessas espécies, assim como foram avaliados os bancos de sementes dos solos de áreas do Cerrado e de Matas de Galeria, com e sem perturbações. O estudo do comportamento germinativo das sementes revelou que, uma vez aplicados os tratamentos para superação da dormência, todas as espécies apresentam elevado percentual de germinação, independentemente das condições de luz. A escarificação mecânica e o corte do tegumento aceleram a germinação de Sclerolobium paniculatum var. subvelutinum e Solanum lycocarpum, enquanto Cecropia pachystachya apresentou dormência fisiológica superada por ácido giberélico e nitrato de potássio. As três espécies apresentam comportamento similar quanto à germinação em diferentes condições de luz, uma vez superada a barreira da dormência. O desenvolvimento das variáveis alométricas e a produção de biomassa indicaram a necessidade de elevados percentuais de luz para o desenvolvimento destas, confirmando seu caráter pioneiro. O estudo do banco de sementes da Cascalheira, do Cerrado sensu stricto com e sem perturbação, das Matas do Capetinga e do Gama, com e sem perturbação, mostrou que,quanto maior o grau de perturbação, maior o estoque do banco de sementes formado por diásporos com características de gramíneas, em detrimento de espécies arbóreas. Constatou-se a existência de um gradiente no Cerrado sensu stricto no qual a relação sementes viáveis/sementes totais do banco foi: Cerrado não-perturbado > Cerrado perturbado por fogo e desmatamento > Cascalheira. Também no caso da Mata de Galeria do Capetinga houve uma nítida distinção entre área perturbada (com clereira) e não (ou menos) perturbada (interior da mata), sendo: Mata do Capetinga não perturbada > Mata do Capetinga perturbada. Contudo, na Mata de Galeria do Gama, por se tratar de uma mata mais conservada do que a do Capetinga, a relação sementes viáveis/sementes totais do banco foi semelhante para ambas as condições (borda e interior da mata), sendo possível a recuperação das áreas degradadas através do banco de sementes. / Sclerolobium paniculatum Vogel var. subvelutinum Benth. and Solanum lycocarpum A. St.-Hil. are typical species of the Cerrado sensu stricto that occur mostly in degraded lands by deforestations and fire, while Cecropia pachystachya Trécul occurs mostly in Gallery forest gaps. The objective of this work was to detect the pioneer behavior of these three species, through the analysis of germination and initial growth. Moreover, seed banks in the Cerrado sensu stricto and Gallery forest areas, with and without disturbances, were evaluated. The study of the seeds germinative behavior showed that once applied adequate treatments to overcome dormancy, all the species presented high germination levels, independent of light conditions. Mechanic scarification and seed tegument cutting accelerated germination of Sclerolobium paniculatum var. subvelutinum and Solanum lycocarpum, while physiological dormancy of Cecropia pachystachya was surpassed by giberelic acid and potassium nitrate. The three species showed a similar behavior related to germination at various light conditions, since the dormancy barrier was surpassed. The pioneering character was confirmed since alometric variables and biomass production was associated with high light percentages. The seed banks studies showed that a higher number of grass diaspora was found in the more degraded areas, replacing the forest trees species seed bank. These results suggested a gradient in relation to viable seeds/total seeds in the seed bank of the Cerrado sensu stricto: not disturbed Cerrado > Cerrado disturbed by fire and deforestation > Gravel pit. In the Capetinga gallery forest, that is a forest disturbed by fire, there was a clear distinction between a degraded area (large gap) and a less disturbed one. However, in the Gama gallery forest, that is a less disturbed forest, the relation viable seeds/total seeds was similar between disturbed and undisturbed areas (interior of the forest), allowing to state that the recovery of disturbed areas, in this forest, could occur naturally through the seed bank. / Não foi localizado o cpf do autor.
585

Puesta en valor de variedades tradicionales de tomate

Cortés Olmos, Carles 31 March 2015 (has links)
Las variedades tradicionales de tomate son apreciadas por los consumidores, que están dispuestos a pagar mayores precios por recuperar el sabor del tomate. Este interés ha propiciado que los estudios referentes a estos materiales se hayan multiplicado durante los últimos años, aunque normalmente se ciñen a pocas variedades, pocas poblaciones por variedad, o a aspectos muy concretos de sus características. El presente trabajo aborda una caracterización de variedades tradicionales del levante español que permita reunir e integrar los resultados de caracterización morfo-agronómica, organoléptica, funcional y molecular, en un intento de poner en valor estos importantes recursos fitogenéticos. Dentro de las poblaciones de las variedades tradicionales evaluadas se han observado niveles elevados de variación en características morfo-agronómicas y funcionales. Dicha variación puede deberse a factores micro-ambientales o diferencias genotípicas, puesto que se trata de variedades población. No obstante, las diferencias observadas en los niveles de variación respecto a híbridos F1 empleados como control, sugiere que las diferencias genotípicas entre individuos no serían tan importantes como cabría pensar. La variación detectada entre poblaciones de la misma variedad es, en general, mayor en todos los niveles (morfo-agronómico, organoléptico, funcional y molecular). Aunque parece existir una cierta tendencia en el perfil organoléptico, funcional y morfológico para cada variedad, lo cierto es que los rangos de variación de estos perfiles entre distintas variedades se solapan. La selección diferencial realizada por cada agricultor dentro de variedad podría ser una de las principales causas de la elevada variabilidad detectada. A ésta se añade los efectos de la mezcla de semillas y los cruzamientos espontáneos que se han evidenciado en la evaluación de los materiales (tanto por segregación morfo-agronómica como por los niveles de heterocigosidad observada en algunas poblaciones). De esta forma, tras estos sucesos el agricultor aplicaría una elevada presión de selección para recuperar las características básicas externas de la variedad, pero la variación se mantendría, especialmente, en los caracteres internos. La elevada variabilidad entre las poblaciones de una misma variedad presenta varios problemas a la hora de abordar la promoción de su cultivo y su conservación in situ. Por un lado, la existencia de tanta variación complica que los consumidores asocien un morfotipo muy definido con un elevado estándar de calidad. Además, la falta de un ideotipo claro y relativamente uniforme, dificulta el registro de los materiales como variedades de conservación. Por otro lado, no todas las poblaciones de una variedad aglutinan una morfología y estructura del fruto adecuada, representativa de la variedad y que además manifieste el mejor sabor posible. Por ello, es conveniente llevar a cabo programas de depuración varietal en los que se realicen selecciones de las mejores poblaciones que reúnan las mejores características. Por otro lado, también sería recomendable realizar selecciones dentro de población en los casos en los que la variación intra-poblacional sea excesiva. En ocasiones, y de forma complementaria, podría contemplarse la introgresión de genes de resistencia a virosis en variedades tradicionales, como medida necesaria en aquellas zonas especialmente afectadas por determinadas enfermedades. De forma adicional, considerando el creciente interés por los alimentos saludables, la detección de variedades o poblaciones dentro de variedad que destaquen por un elevado valor funcional, puede contribuir a identificar un valor añadido que permita valorizar estas variedades tradicionales. En este contexto, se han encontrado poblaciones con niveles de vitamina C próximos a los mostrados por cultivares “Double Rich”, de licopeno dentro del rango de variación mostrado por cultivares “high pigment” y de β-caroteno comparables a los mejores resultados obtenidos en cultivares “high pigment”. Estos materiales resultan potencialmente útiles como fuentes de variación o pueden ser directamente aprovechables para ser reintroducidos en el mercado con un valor añadido contrastado. Aunque se ha encontrado variación para el contenido en polifenoles totales, éstos han sido intermedios. Finalmente, a la hora de realizar una adecuada identificación del ideotipo varietal, de depurar una variedad descartando poblaciones, de acelerar programas de introgresión de genes o simplemente para defender los mercados de calidad frente a fraudes que pretendan aprovechar los diferenciales de precio de las variedades tradicionales, es necesario contar con herramientas de caracterización molecular eficientes. En este trabajo se ha seleccionado y comprobado la efectividad de una colección de marcadores SNP para caracterizar variedades tradicionales de tomate y se han obtenido huellas moleculares para las variedades: “Centenares”, “Cuarenteno”, “De la pera”, “De pera”, “Flor de baladre”, “Gordo rojo”, “Moruno”, “Muchamiel”, “Negre”, “Pimiento”, “Valenciano” y “Tomaca gallega”. La tipificación varietal, la identificación de un valor añadido en las características organolépticas y funcionales de estos materiales, y la detección de perfiles moleculares que permitan autentificarlos, son elementos clave y necesarios para asegurar la protección de estos recursos genéticos. Estas actividades contribuirán a consolidar los mercados de calidad, satisfaciendo las demandas de los consumidores, y ofreciendo una alternativa de cultivo rentable a agricultores en sistemas minifundistas. / Cortés Olmos, C. (2015). Puesta en valor de variedades tradicionales de tomate [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48532 / TESIS
586

Adubação mineral na cultura da batata e do residual no feijoeiro /

Feltran, José Carlos, 1969- January 2005 (has links)
Orientador: Leandro Borges Lemos / Banca: Dirceu Maximino Fernandes / Banca: Domingos Fornasieri Filho / Banca: Paulo Cesar Tavares de Melo / Banca: Newton do Prado Granja / Resumo: A cultura da batata tem grande importância econômica para o Brasil e o Estado de São Paulo, sendo Vargem Grande do Sul e Itapetininga os principais pólos produtores paulistas. Nestes, além da cultura da batata, a do feijoeiro destaca-se por sua importância econômica e social. Geralmente os produtores utilizam o feijoeiro em sucessão à batata e objetivando obter alta produtividade de grãos, realizam a adubação de semeadura, desprezando a possível influência residual da adubação da batata. O trabalho objetivou avaliar a influência da adubação de plantio na cultura da batata, da fertilização residual da batata e de semeadura sobre o feijoeiro em sucessão. Para isso foram avaliados por meio de sua contribuição nas características agronômicas e nutricionais das plantas, das alterações nos atributos químicos do solo, bem como a combinação recomendada da adubação de plantio e de semeadura para a batata e o feijão quanto ao retorno econômico. Foram conduzidos dois experimentos, sendo o primeiro em Itapetininga (SP) num Nitossolo Vermelho Distroférrico típico, textura argilosa e o segundo em São Manuel (SP) num Latossolo Vermelho-Amarelo Distrófico típico, textura média. Em ambos foi utilizado o delineamento experimental de blocos casualizados em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram constituídas das adubações de plantio da batata (0, 1.000, 2.000, 3.000 e 4.000 kg ha-1 de 8-28-16) e as subparcelas pela adubação de semeadura do feijoeiro (0 e 330 kg ha-1 de 8-28-16 em Itapetininga e 0, 150, 300 e 450 kg ha-1 de 8-28-16 em São Manuel). Foram utilizadas as cultivares de batata e de feijão Agata e Pérola, respectivamente. Para o solo de textura argilosa a produtividade total e comercial de tubérculos aumentou até a dose próxima de 3.000 kg ha-1 de 8-28-16. A produtividade...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Potato crop has great economical importance for Brazil and São Paulo State. In São Paulo State, Vargem Grande do Sul and Itapetininga are the main producing areas, where beans crop also plays a major economical and social role. Usually, growers plant beans crop after potato crop, aiming high grain yield. They make sowing fertilization and ignore the possible residual influence of potato fertilization. Therefore, the purpose of this research was to evaluate the planting fertilization influence on the potato crop, the residual potato fertilization influence on beans crop in sequence to potato crop, through its contribution in the plant nutrition and agronomic characteristics, and changes in electrical conductivity and chemical soil attributes. This study also tries to find the best economic combination of sowing and planting fertilization recommended for potato and beans crop. Two experiments were carried out, the first one being in Itapetininga (SP) in a typical "Nitossolo Vermelho Distroférrico", clay texture, and the second one in São Manuel (SP) in a typical "Latossolo Vermelho-Amarelo Distrófico", sandy loam texture. The experimental design was in randomized blocks with split plot analyses, with four replicates. The plot treatments consisted of potato fertilization (0, 1,000, 2,000, 3,000 and 4,000 kg ha-1 of 8-28-16) and the split plot of beans sowing fertilization (0 and 330 kg ha-1 of 8-28-16 in Itapetininga, and 0, 150, 300 and 450 kg ha-1 of 8-28-16 in São Manuel). Agata and Pérola varieties for potato and beans, respectively, were used in the experiments. For the clay texture the total and commercial tuber yields increased until near 3,000 kg ha-1 of 8-28-16. No grain yield response to potato fertilization residual was observed. The beans crop fertilization reduced the grain yield. The use of 8-28-16 fertilization increased the P, K and Ca and CE contents in the soil...(Complete abstract click electronic access below) / Doutor
587

Transformace lilku bramboru genem kódujícím proteázový inhibitor SPI-2 / Transformation of potato with protease inhibitor gene SPI-2

Říhová, Barbora January 2013 (has links)
The subject of my thesis was to genetically modify a potato for increased resistance against its pathogens and pests. In developing a resistant plant, it is quite common to use the same type of molecules that plants use themselves in their defense reactions. In this work I used the gene SPI-2 originating from a honeycomb moth (Galleria mellonella). The protein SPI-2 is a member of serine protease inhibitors. Since the previous attempts of the team to detect the protein in transformed plants haven't been successful, the basic form of the gene was modified by adding a Kozak sequence near the start codon, which should have increased the translation initiation and hence increase the level of the protein. Two constructs were prepared for the transformation: SPI-2-T a SPI-2-Y. They differ by one amino acid, which slightly changes their inhibitory activity. First, the construct SPI-2-T was used for a transient transformation of tobacco Nicotiana benthamiana by agroinfiltration of its leaves. Then both constructs were used for a stable transformation of Solanum tuberosum cv. Desireé. The detection of the protein has not been successful, although the inserted gene was transcribed and his sequence was verified by sequencing. It is therefore most likely that the protein has a low stability in the cytoplasm....
588

Generación de líneas T-DNA de tomate (Solanum Lycopersicon cv.p73) e identificación de mutantes de inserción.

Angarita Díaz, Mª del Pilar 17 February 2012 (has links)
El empleo de herramientas genómicas ayudará a superar dos de los retos que todavía subsisten en el campo de la mejora molecular (i.e., vía transformación): la identificación de los genes que realmente controlan los caracteres de interés agronómico y la detección de señales de regulación que permitan modular la expresión de los transgenes a nivel espacial y temporal. Entre las vías para lograr tales objetivos, destaca la mutagénesis insercional por T-DNA, que en los últimos años se ha convertido en una herramienta básica para la identificación y etiquetado de genes, así como para el análisis de su función. En efecto, la disrupción de un gen endógeno o la integración del T-DNA en la vecindad del mismo pueden ocasionar la anulación o alteración de función, dando una valiosa información sobre el papel de un cierto gen en un carácter dado. Otra aplicación de la mutagénesis insercional por T-DNA estriba en la detección de elementos de regulación mediante el empleo de los denominados "sistemas trampa" (trapping) que permiten detectar secuencias reguladoras y asignar una función a partir de datos de expresión del delator que mimetiza la expresión del gen endógeno. El aspecto más relevante de estas aproximaciones es que, tras la identificación de un cierto gen, éste queda etiquetado por el T-DNA, lo que facilita su clonación. El principal objetivo de esta Tesis Doctoral ha sido la generación una colección de líneas de inserción por T-DNA en tomate y la identificación de mutantes afectados en caracteres relacionados con el desarrollo. En concreto, se han generado más de 1200 líneas T-DNA y se han obtenido sus descendencias TG2. La caracterización de estas líneas en TG1 ha conducido a la detección de 255 mutantes (de tipo dominante, semidominante o aditivo) afectados en caracteres vegetativos y/o reproductivos. Asimismo, se ha caracterizado una pequeña muestra de progenies TG2 (en concreto 37) lo que ha permitido la identificación de 6 mutantes recesivos. / Angarita Díaz, MDP. (2009). Generación de líneas T-DNA de tomate (Solanum Lycopersicon cv.p73) e identificación de mutantes de inserción [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14718 / Palancia
589

Rediscovering pepper, eggplant and lettuce landraces of the Valencian Community; an ancient resource with vast potential for the future

Martínez Ispizua, Eva 05 January 2023 (has links)
Tesis por compendio / [ES] La erosión genética provocada en los cultivos al primar producción sobre calidad ha derivado en pérdida de biodiversidad, lo que compromete la seguridad alimentaria mundial. Los agricultores, a través de un proceso histórico de selección, han ido diferenciando variedades tradicionales de cultivo que sonfuente de biodiversidad agrícola que además favorece el desarrollo de la economía local. Por este motivo, su recuperación, clasificación y cultivo son clave para la economía y futuro alimentario. La conservación de las variedades tradicionales requiere un conocimiento de las mismas a través de la descripción detallada de las características fenotípicas, agronómicas, y de calidad nutricional como valor añadido. La Comunitat Valenciana, cuenta con un extenso patrimonio hortícola constituido por una gran diversidad de variedades tradicionales de hortalizas. Estas son fruto de la adaptación a variadas condiciones agroclimáticas de la geografía valenciana, por un lado, y de la selección aplicada por los agricultores en cada localidad por otro. En este sentido, estas variedades tienen un gran valor como patrimonio etnobotánico y como tal deberían ser conservadas. Asimismo, en la actualidad, el cultivo y el consumo de las variedades tradicionales están creciendo, ya que son especialmente atractivas para los consumidores por su diversidad y su alta calidad nutracéutica. En este contexto, esta tesis doctoral se basa en la caracterización fenotípica y nutricional para valorizar las variedades tradicionales de la comunidad, correspondientes a los cultivos de pimiento, berenjena y lechuga, con la finalidad de promover su conservación y cultivo en las zonas de origen, e impulsando la diversidad. La caracterización morfológica de las variedades autóctonas ha sido objeto de numerosos estudios, necesarios porque proporcionan información sobre los caracteres fenotípicos diferenciadores, y contribuyen a optimizar los programas de mejora vegetal. En este sentido, la caracterización de las variedades hortícolas valencianas seleccionadas se realizó siguiendo las directrices del IBPGR. Además, en esta tesis doctoral se han realizado estudios sobre el valor nutracéutico de las tres variedades seleccionadas por ser uno de los principales intereses del consumidor. Por ello, el contenido de algunos compuestos bioactivos y antioxidantes (fenoles, flavonoides, antocianinas, ácido ascórbico, licopeno, carotenoides, clorofilas y la actividad antioxidante), azucares y minerales fueron monitoreados para establecer parámetros de calidad en las especies mencionadas. También se determinó los parámetros indicativos de estrés oxidativo, para establecer la capacidad de conservación de atributos físico-químicos de la lechuga en el ensayo de post-cosecha. / [CA] L'erosió genètica provocada en els cultius com a conseqüència de posar per davant producció sobre qualitat ha derivat en pèrdua de biodiversitat, fet que compromet la seguretat alimentària mundial. Els agricultors, a través d'un procés històric de selecció, han generat la diferenciació varietats tradicionals de cultiu que hui són font de biodiversitat agrícola. A més, s'afavoreix el desenvolupament de l'economia local. Per aquest motiu, la seva recuperació, classificació i cultiu són clau per a l'economia i el futur alimentari. La conservació de les varietats tradicionals requereix un coneixement de les mateixes mitjançant la descripció detallada de les seues característiques fenotípiques, agronòmiques, i de qualitat nutricional com a valor afegit. La Comunitat Valenciana compta amb un extens patrimoni hortícola constituït per una gran diversitat de varietats tradicionals d'hortalisses. Aquestes són fruit de l'adaptació a diverses condicions agroclimàtiques de la geografia valenciana, d'una banda, i de la selecció aplicada pels agricultors a cada localitat de l'altra. En aquest sentit, aquestes varietats tenen un gran valor com a patrimoni etnobotànic i com a tal haurien de ser conservades. Així mateix, actualment, el cultiu i el consum de les varietats tradicionals estan creixent, ja que són especialment atractives per als consumidors per la seua diversitat i la seua alta qualitat nutracèutica. En aquest context, aquesta tesi doctoral es basa en la caracterització fenotípica i nutricional per valoritzar les varietats tradicionals de la Ccomunitat, corresponents als cultius de pebre, albergínia i encisam, amb la finalitat de promoure'n la conservació i el cultiu a les zones d'origen, i impulsant la diversitat. La caracterització morfològica de les varietats autòctones ha estat objecte de nombrosos estudis, necessaris perquè proporcionen informació sobre els caràcters fenotípics diferenciadors, i contribueixen a optimitzar els programes de millora vegetal. En aquesta línia, la caracterització de les varietats hortícoles valencianes seleccionades es va fer seguint les directrius de l'IBPGR. A més, en aquesta tesi doctoral s'han fet estudis sobre el valor nutracèutic de les tres espècies seleccionades per ser un dels principals interessos del consumidor. Per això, el contingut d'alguns compostos bioactius i antioxidants (fenols, flavonoides, antocianinas, àcid ascòrbic, licopè, carotenoides, clorofil·les i l'activitat antioxidant), sucres i minerals van ser monitoritzats per establir paràmetres de qualitat a les espècies esmentades. També es van determinar els paràmetres indicatius d'estrès oxidatiu, per establir la capacitat de conservació d'atributs fisicoquímics de l'encisam a l'assaig de postcollita. / [EN] Genetic erosion in crops, gained from prioritising production over quality, has led to biodiversity loss, which compromises global food security. By a historic selection process, farmers have been differentiating traditional crop varieties, which are a source of agricultural biodiversity that also favours the development of local economy, which makes their recovery, classification and cultivation key for food economy and the future. The conservation of traditional varieties requires knowledge of them, obtained from a detailed description of their phenotypical, agronomic and nutritional quality characteristics as added value. The Valencian Community (east Spain) has extensive horticultural heritage that is made up of a high diversity of traditional vegetable varieties. These are the result of adapting to the varied agroclimate conditions of the Valencian geography: on the one hand, the selection applied by farmers to each locality; on the other hand, these varieties are very valuable as ethnobotanical heritage and should be preserved. Moreover, the cultivation and consumption of traditional varieties are currently growing because they are particularly appealing to consumers for their diversity and high nutraceutical quality. In this context, the present doctoral thesis is based on a phenotypical and nutritional characterisation to evaluate traditional varieties in the Valencian Community, which correspond to pepper, eggplant and lettuce crops, to promote their conservation and cultivation in areas of origin, and to boost diversity. The morphological characterisation of landraces has been the subject of many studies, which are necessary because they provide information about differentiating phenotypical characteristics and help to optimise plant-breeding programmes. The characterisation of the selected Valencian vegetable varieties was carried out following IBPGR guidelines. Furthermore, studies were conducted in this doctoral thesis into the nutraceutical value of the three selected crops because this value is one of the main consumer interests. The content of some bioactive compounds and antioxidants (phenols, flavonoids, anthocyanins, ascorbic acid, lycopene, carotenoids, chlorophylls, antioxidant activity), sugars and minerals were monitored to establish quality parameters in the aforementioned species. Parameters indicative of oxidative stress were also determined to establish the conservation capacity of the physico-chemical attributes of lettuce in the post-harvest test. / Martínez Ispizua, E. (2022). Rediscovering pepper, eggplant and lettuce landraces of the Valencian Community; an ancient resource with vast potential for the future [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191053 / Compendio
590

Naturally occurring variation in the promoter of the chromoplast-specific Cyc-B gene in tomato can be used to modulate levels of ß-carotene in ripe tomato fruit

Orchard, Caleb January 2014 (has links)
No description available.

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