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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.
41

Efeito do Cloreto de SÃdio sobre o crescimento e acumulaÃÃo de nutrientes da Mamoneira / Effect of sodium chloride on the development and absorption of nutrients of castor bean

CÃcera Raquel Fernandes Rodrigues 05 March 2007 (has links)
nÃo hà / Recentemente, especial Ãnfase tem sido direcionada ao cultivo da mamoneira, contudo, poucos sÃo os resultados disponÃveis na literatura sobre o real potencial desta cultura em se desenvolver e produzir quando cultivada em Ãreas salinizadas. Por tratar-se de uma cultura naturalmente vigorosa, de fÃcil propagaÃÃo e que pode apresentar relevante importÃncia social e econÃmica para o paÃs, especialmente para o nordeste e considerando os escassos estudos relacionados, visou-se neste trabalho, avaliar a tolerÃncia da salinidade e seus efeitos sobre os teores de nutrientes na planta. Foi instalado um experimento casa de vegetaÃÃo em condiÃÃes hidropÃnicas. Usou-se 10 tratamentos de salinidade correspondentes a CE da soluÃÃo nutritiva de 1,7; 2,5; 3,0; 4,0; 5,0; 6,0; 7,5; 9,0, 12,5 e 15,0 dS/m. o delineamento experimental adotado foi inteiramente ao acaso, com trÃs repetiÃÃes. A salinidade afeta negativamente o crescimento das plantas de mamona e acarreta sintomas visuais de toxidez, caracterizados por queima das bordas e Ãpice das folhas e, em estÃgio mais avanÃado, amarelecimento do limbo e queda das mesmas, à considerada moderadamente sensÃvel a salinidade, apresentando a salinidade limiar està entre 1,7 a 2,5 dS/m, houve aumentos nos teores de fÃsforo nas raÃzes da mamona, decrÃscimos nos teores de potÃssio nas folhas, o cÃlcio e o magnÃsio tiveram seus teores constantes, sendo que o cÃlcio apresentou maiores acÃmulos nas folhas, os teores do zinco foram maiores nos caules, enquanto que o cobre apresentou maior acumulo nas raÃzes, tanto o ferro, quanto o manganÃs apresentaram maiores teores nas raÃzes e os teores de sÃdio e cloro aumentaram significativamente em todas as partes da planta com o aumento da salinidade, sendo os teores de cloro, maiores que sÃdio. Para os dois Ãons Na+ e Cl-, ocorreu maior acumulo ocorreu nas raÃzes, seguidos dos caules e folhas. / Special emphasis has recently been given to the culture of castorbean, however available results about the potential of this culture to develop and to produce when cultivated in salinized areas are not greatly found in the literature. To be a vigorous culture and to disseminate easily it can be of great social and economic importance for Brazil and especially for the Northeast region. Thus, considering the scarce related studies, the current work was aimed to evaluate the tolerance to salinity of this plant species as well the effects of different salinity levels in the nutrient solution on the plant growth. The plants were hidroponically cultivated under greenhouse conditions. The treatments consisted of ten salinity levels that corresponded to the following nutrition solutions CEâ s: 1,7; 2,5; 3,0; 4,0; 5,0; 6,0; 7,5; 9,0; 12,5 e 15,0 dS/m. The experiment was an entirely randomized block design with three replications. The salinity negative affects the castorbean growth and causes visual symptoms of toxicity, which had been characterized by burning of the edges and apex of leaves. With increasing toxicity symptoms intensity the leaves yellowed then dropped off. Castorbean is considered a moderately sensitive plant species to salinity and it has salinity threshold between 2,5 and 1,7 dS/m. It was seen that phosphorus increased in the castorbean roots while potassium of leaves decreased; the calcium and magnesium concentrations kept constant in the roots, and in the leaves calcium concentrated more. The zinc concentration was higher in the stem while cupper was higher in the roots. Iron and manganese concentrated more in the roots and the contents of sodium and chloride significantly increased, mainly of chloride, with increasing external salinity in all plant parts. The sodium and chloride concentrations were higher in the roots followed by leaves and stem.
42

Tolerance of selected crops to gypsiferous water originating in coal mines

Mentz, Wilma Henriette 11 November 2003 (has links)
The disposal of gypsiferous water, generated in coal mining operations, has become a problem in the Mpumalanga Highveld region in South Africa. As part of an investigation into the feasibility of using this water for irrigation, sand and water culture experiments were conducted in a glasshouse and growth chambers to determine growth responses of maize, sorghum, pearl millet, sunflower, soybean, cowpea, dry bean, wheat, rye, triticale, oats, barley, annual ryegrass, and lucerne cultivars to gypsiferous mine water in the germination, seedling and vegetative growth stages. Germination %’s were generally not affected. The seedling growth of maize, sorghum, pearl millet and lucerne was more sensitive and showed more significant cultivar differences than the seedling growth of soybean and the annual temperate crops. Seedling growth curves with increasing concentrations of Ca, Mg and SO4 followed a similar pattern for most of the crops: where CaSO4 was in solution, growth decreased in a linear manner, but above saturation concentrations with increasing gypsum crystal content, it increased despite decreasing osmotic potentials of the treatment solutions. The vegetative growth of sunflower, lucerne, dry bean and rye was more tolerant than seedling growth, but was more sensitive for maize and cowpea, and the same as seedling growth for sorghum, pearl millet, wheat, oats, triticale and annual ryegrass. It was concluded that the major property of this water that suppressed growth was the decreased osmotic potential. However, it is the ‘effective’ osmotic potential (i.e., the average osmotic potential during the whole growth period) and not that of the treatment solutions, that was mainly responsible for the eventual growth. The ‘effective osmotic potential’ is determined by evapotranspiration and the rapidity of gypsum precipitation, which in turn may be affected by the growth rate, temporal, environmental and soil factors. Sensitivity of crops and growth stages is therefore related to its sensitivity to the external osmotic potential, whereas tolerance both in the seedling and vegetative growth stages was found in crops primarily affected by the ionic effects of Na and/or Cl. Possible nutrient effects due to the high Ca and SO4 need further investigation. / Thesis (PhD (Plant Production and Soil Science))--University of Pretoria, 2004. / Plant Production and Soil Science / unrestricted
43

Biotechnological tools applied to the improvement of persimmon (Diospyros kaki Thunb) culture.

Gil Muñoz, Francisco 26 October 2020 (has links)
[ES] El cultivo del caqui ha crecido enormemente en la región Valenciana en los últimos 20 años al presentarse como una alternativa interesante al cultivo de cítricos. Sin embargo, su cultivo se enfrenta a tres problemas importantes. En primer lugar, su producción es monovarietal y se centra en la variedad Rojo Brillante, lo que conlleva un riesgo sanitario y de mercado importante que pone de manifiesto la necesidad de aumentar el número de variedades disponibles. En segundo lugar, el cambio climático pone en peligro la producción de caqui en zonas mediterráneas debido a un aumento en la salinidad del agua y suelo. La salinidad afecta especialmente al caqui debido a sus efectos sobre la producción, calidad y postcosecha de la fruta. La falta de patrones tolerantes a la salinidad compatibles con las condiciones de cultivo además agrava este problema, por lo que es necesario el desarrollo de patrones clonales tolerantes a la salinidad. En tercer lugar, la industria del caqui está basada en la aplicación de tratamientos postcosecha de desastringencia. Aunque existen variedades naturalmente no astringentes, su uso en el Mediterráneo es complicado debido a la incompatibilidad con los patrones existentes. Además, la salinidad afecta gravemente la eficacia del tratamiento de desastringencia. Por ello, cabe destacar que se necesita más información acerca de los mecanismos moleculares que controlan el desarrollo de la astringencia para poder desarrollar nuevas variedades y/o unos tratamientos de desastringencia más efectivos. En el contexto de la mejora genética y la biología molecular, pueden distinguirse tres objetivos para mejorar las condiciones de cultivo en esta región: el desarrollo de nuevas variedades de caqui con una época de madurez distinta a Rojo Brillante, el desarrollo de patrones clonales tolerantes a la salinidad y compatibles con variedades no astringentes y la obtención de nuevos conocimientos acerca de las bases moleculares del mecanismo de regulación de la astringencia para optimizar los tratamientos postcosecha. La presente tesis ha contribuido a estos tres objetivos. Respecto a la obtención de nuevas variedades, se ha desarrollado un análisis de diversidad genética del banco de germoplasma del IVIA, lo que es un recurso importante para la planificación de cruces. Para asegurar una mejora genética eficiente y evitar redundancias en la colección, se ha efectuado un análisis de diversidad usando secuencias microsatélites. El análisis ha arrojado datos de gran utilidad, como el descubrimiento de alelos únicos, que permiten la identificación rápida de variedades, o la división de la colección de acuerdo con el tipo de astringencia del fruto, confirmando el fondo genético común de las accesiones que comparten este carácter. Además, el mapa de las relaciones filogenéticas generado será de gran utilidad para la planificación futura de cruces dentro del programa de mejora de caqui. Para abordar el problema de la salinidad, se han realizado distintos ensayos de estrés salino en invernadero con distintas poblaciones de especies utilizadas como patrón de caqui: Diospyros virginiana (tolerante a salinidad), Diospyros kaki (sensible a salinidad y compatible) y Diospyros lotus (sensible a salinidad). Además, debido a los caracteres de gran interés presentes en estas dos especies, se incluyó en los ensayos una población proveniente de un retrocruce entre D. kaki y D. virginiana. Como resultado, varios individuos de estas poblaciones se han seleccionado debido a su tolerancia a la salinidad, ya que podrían tener las características adecuadas para ser patrones clonales. Complementariamente, se han usado aproximaciones fisiológicas, transcriptómicas y de secuenciación masiva de transcriptoma para hacer una primera descripción de los mecanismos de tolerancia a la salinidad presentes en estas especies. Como resultado, se han descrito los principales caracteres relacionados con la tolerancia a la salinidad en el género Diospyros, como la compartimentalización de iones, la expresión en raíz de un gen similar a HKT-1, la abundancia de canales de cloruro o la arquitectura de raíz. Finalmente, para obtener más información sobre la biosíntesis de proantocianidinas, la molécula responsable de la astringencia, se formuló la hipótesis de la existencia de un complejo proteico del tipo MBW (MYB-bHLH-WD40) que podía regular la ruta molecular de forma análoga a la regulación existente en otras especies estudiadas. En primer lugar se secuenció un gen tipo WD40, posible ortólogo de TTG1 de Arabidopsis thaliana. El papel de este gen y otros genes del hipotético complejo (MYB2, MYB4 y MYC1) han sido estudiados mediante un análisis transcriptómico en distintos estadios de madurez de frutos astringentes y no astringentes. Además, se ha observado mediante microscopía la localización celular de estos genes mediante la expresión transitoria con fusión con fluorescencia en hojas de Nicotiana benthamiana y hemos analizado su interacción mediante ensayos de doble híbrido en levadura y BiFC (complementación bimolecular de fluorescencia) mediante expresión transitoria en hojas de Nicotiana benthamiana. Finalmente, hemos analizado los efectos de estos genes y de sus interacciones en la ruta de biosíntesis de proantocianidinas usando el promotor del gen ANR (antocianidin reductasa) y promotores de los genes reguladores MYC1 y MYB4, fusionándolos con una luciferasa como gen delator y coexpresándolos con distintas combinaciones de los genes del complejo MBW mediante expresión transitoria en hojas de Nicotiana benthamiana. Los resultados de estos ensayos confirman la interacción nuclear de estos genes y su papel en la regulación de la producción de la astringencia, dando lugar a un modelo básico con algunas diferencias a los propuestos en otras especies. / [EN] Persimmon culture has vastly grown in the last 20 years as an alternative to citrus production in the Valencian region. However, its production faces three important problems. First, monovarietal production based on Rojo Brillante is a sanitary and market risk that requires to increase the number of varieties available. Second, climate change has threatened persimmon production in the Mediterranean areas because the salinity increase in water and soil. Salinity severely affects production, quality and postharvest life of the fruit. The lack of salt-tolerant rootstocks compatible with the cultural conditions aggravates the problem; hence clonal salt-tolerant rootstocks are needed. Third, persimmon industry relies on the postharvest deastringency treatment of the varieties. Even though there are varieties that are naturally non-astringent, its culture in the Mediterranean area is limited due to rootstock incompatibility. Additionally, the costly postharvest treatment is also affected by salinity. Consequently, more information is needed about the molecular mechanism of astringency biosynthesis in persimmon fruit in order to develop new varieties and/or more effective treatments for removing astringency of the fruit. In the context of breeding and molecular biology, three goals need to be approached in order to improve the cultural conditions: development of new persimmon varieties with maturity date different from Rojo Brillante, development of salt-tolerant clonal rootstocks compatible with non-astringent varieties and research on the molecular bases of the mechanism of astringency production to optimize the postharvest treatments. This research contributes and provides knowledge to address these goals. Concerning breeding of new varieties, the IVIA persimmon germplasm collection is an important resource for breeding of new varieties. To ensure efficient breeding and avoid redundancy in the collection, a SSR analysis was carried out to solve this problem. This analysis has provided useful data, such as the discovery of unique alleles, that allows rapid identification of varieties or the division of the population according to its astringency type, confirming the common genetic background of the accessions concerning to this trait. The generated genetic diversity map will be useful for designing crosses in the breeding program. To address the salinity problem, several salt-stress assays were done in greenhouse using different persimmon rootstocks populations: Diospyros virginiana (salt-tolerant), Diospyros kaki (salt-sensitive fully compatible) and Diospyros lotus (salt-sensitive). Furthermore, due to the desirable characters present in these species, a backcross progeny between D. kaki and D. virginiana was obtained and included in the salt-stress assays. Thus, several individuals from all the populations have been selected, which are tolerant to salinity and could meet the desired characteristics for appropriate persimmon clonal rootstocks. Furthermore we have used physiological, transcriptomic and mass transcriptome sequencing approaches in order to discover the physiological and genetic bases of salinity tolerance in these species. As a result, we described the main facts related to salinity tolerance mechanisms in Diospyros species, such as ion compartmentalization, HKT-1-like root expression, abundancy of chloride channels and root architecture. Finally, in order to get a deeper insight on the biosynthesis of proanthocyanidins, the responsible molecule of astringency, we hypothesized the presence of a MBW protein complex (MYB-bHLHWD40) in persimmon fruit, involved in the regulation of the proanthocyanidins synthesis pathway in a similar way to other species. We firstly sequenced the putative persimmon WD40 orthologue of TTG1 gene from Arabidopsis thaliana. The role of this gene and other genes of the complex (MYB2, MYB4 and MYC1) was studied through transcriptomic analysis in different stages of nonastringent and astringent fruit. Furthermore, we have observed through microscopy the subcellular localization of these genes using fluorescent protein fusions and transient expression in Nicotiana benthamiana leaves, and analyzed its interaction through yeast twohybrid assays and BiFC (bimolecular fluorescence complementation) experiments in Nicotiana benthamiana leaves. In addition, we have analyzed the effects of these interactions in the pathway of proanthocyanidin biosynthesis using the ANR (anthocyanidin reductase) gene promoter and the promoters of some of these genes (MYB4 and MYC1) fused with a luciferase reporter, together with the coexpression of the MBW genes using transient expression in Nicotiana benthamiana leaves. The results of these assays have confirmed the nuclear interaction of these genes and its role in the regulation of astringency biosynthesis, providing a basic model with some differences with respect to the models proposed in other species. / [CA] El cultiu del caqui ha crescut enormement en la regió Valenciana en els últims 20 anys al presentar-se com una alternativa interessant al cultiu de cítrics. No obstant, el seu cultiu s’enfronta a tres problemes importants. En primer lloc, la seua producció es monovarietal i està centrada en la varietat Rojo Brillante, el que suposa un risc sanitari i de mercat important que posa de manifest la necessitat de augmentar el nombre de varietats disponibles. En segon lloc, el canvi climàtic posa en perill la producció de caqui a la zona mediterrània degut a un augment en la salinitat del aigua i del sòl. La salinitat afecta de forma especialment al caqui degut al seus efectes sobre la producció, qualitat i vida post collita de la fruita. La falta de patrons tolerants a salinitat compatibles amb les condicions de cultiu a més agreuja aquest problema, pel que es necessari el desenvolupament de patrons clonals tolerants a salinitat. En tercer lloc, la industria del caqui esta basada en la aplicació de tractaments post collita de deastringència. Encara que existixen varietats naturalment no astringents, el seu us al mediterrani es complicat degut a la incompatibilitat en els patrons existents. A més, la salinitat afecta gravement a la eficàcia del tractament post collita de deastringència. Per això, cal destacar que es necessita conèixer millor els mecanismes moleculars que controlen el desenvolupament de la astringència per a la obtenció de noves varietats i/o uns tractaments post collita més efectius. En aquest context de millora genètica i biologia molecular, es poden distingir tres objectius per a millorar les condicions del cultiu en aquesta regió: el desenvolupament de noves varietats de caqui en una època de maduresa distinta a la de Rojo Brillante, el desenvolupament de patrons clonals tolerants a salinitat i compatibles amb varietats no astringents i la obtenció de nous coneixements sobre les bases moleculars del mecanisme de producció de astringència per optimitzar els tractaments post collita. La present tesi ha contribuït a aquests tres objectius. En el que respecta a la obtenció de noves varietats, s’ha desenvolupat un anàlisi de diversitat genètica del banc de germoplasma de l’IVIA, el qual es un recurs important per a la planificació de creuaments. Per a assegurar una millora genètica eficient i evitar redundàncies a la col·lecció, s’ha efectuat un anàlisi en microsatèl·lits. El anàlisi ha resultat en dades de gran utilitat, com el descobriment de al·lels únics, que permiteixen la identificació rapida de varietats, o la divisió de la col·lecció d’acord en el tipus d’astringència del fruit, confirmant el fons genètic comú de les accessions que comparteixen aquest caràcter. A més, el mapa de les relacions filogenètiques elaborat serà de gran utilitat per a la planificació futura de creuaments dins del programa de millora de caqui. Per a abordar el problema de la salinitat, s’han realitzat distints assajos d’estrés salí en hivernacle amb distintes poblacions de patró de caqui: Diospyros virginiana (tolerant a salinitat), Diospyros kaki (sensible a salinitat i amb compatibilitat) i Diospyros lotus (sensible a salinitat). A més, degut als caràcters de gran interès presents en aquestes dos espècies, es va incloure en els assajos una població provenient de un retrocreuament entre D. kaki i D. virginiana. Com a resultat, diversos individus d aquestes poblacions s’han seleccionat degut a la seua tolerància a salinitat, ja que podrien tindre les característiques adequades per a ser patrons clonals. Complementàriament, s’han utilitzat aproximacions fisiològiques, transcriptòmiques i de seqüenciació massiva de transcriptoma per a fer una primera descripció dels mecanismes de tolerància a salinitat presents en aquestes espècies. Com a resultat s’han descrit els principals caràcters relacionats amb la tolerància a la salinitat en el gènere Diospyros, com la compartimentalització de ions, la expressió en arrel de un gen similar a HKT-1, la abundància de canals de clorur o la arquitectura de la arrel. Finalment, per a obtenir mes informació sobre la biosíntesi de proantocianidines, la molècula responsable de la astringència, es va formular la hipòtesi de la existència de un complex proteic del tipus MBW (MYB-bHLH-WD40) que podria regular la ruta molecular de forma anàloga a la regulació existent en altres espècies estudiades. En primer lloc, es va seqüenciar el gen ortòlog putatiu del tipus WD40 de TTG1 de Arabidopsis thaliana. El paper de aquest gen i altres gens del hipotètic complex (MYB2, MYB4 i MYC1) han sigut estudiats mitjançant un anàlisi transcripcional en diferents estats de maduresa de fruits astringents i no astringents. A més, s’ha observat amb microscòpia la localització cel·lular de aquestos gens mitjançant la expressió transitòria amb fusió a fluorescència en fulles de Nicotiana benthamiana i hem analitzat la seua interacció amb un assaig de doble híbrid en llevat i BiFC (complementació bimolecular de fluorescència) mitjançant expressió transitòria en fulles de Nicotiana benthamiana. Finalment hem analitzat els efectes de aquests gens i de les seues interaccions en la ruta de biosíntesi de proantocianidines utilitzant el promotor del gen ANR (antocianidin reductasa) i promotors dels gens reguladors MYC1 i MYB4 fusionant-los amb una luciferasa com a gen delator i coexpressant-los amb diferents combinacions dels gens del complex MBW mitjançant expressió transitòria en fulles de Nicotiana benthamiana. Els resultats de aquests assajos confirmen la interacció nuclear de aquestos gens i el seu paper en la regulació de la producció de la astringència, donant lloc a un model bàsic amb algunes diferències als proposats en altres espècies. / Gil Muñoz, F. (2020). Biotechnological tools applied to the improvement of persimmon (Diospyros kaki Thunb) culture [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/153155 / TESIS
44

Herbicide, Salinity, and Flooding Tolerance of Foxtail Barley (Hordeum jubatum L.) and Desirable Pasture Grasses

Israelsen, Karl R. 01 December 2009 (has links)
Research trials performed in the greenhouse compared the tolerance and response of Hordeum jubatum and desirable pasture grass species to herbicides, salinity, and flooding. Desirable grass species used in this study included: `Fawn' tall fescue (Festuca arundinaceae), `Garrison' creeping foxtail (Alopecurus arundinaceus), `Palaton' reed canarygrass (Phalaris arundinacea), `Climax' timothy (Phleum pratense), `Alkar' tall wheatgrass (Thinopyrum ponticum), `Potomac' orchardgrass (Dactylis glomerata), and `Mustang' altai wildrye (Leymus angustus). Tolerance to herbicides, salinity, and flooding varied significantly among grass species. Herbicide tolerance was tested using four herbicides at five rates each. The herbicides used were imazapic (Plateau), propoxycarbazone (Olympus), sulfosulfuron (Outrider), and flucarbazone (Everest) at rates of 0, 10, 25, 50, 100, and 200 g ha-1. Foxtail barley was least tolerant of sulfosulfuron and propoxycarbazone. Tall fescue, creeping foxtail, and reed canarygrass were susceptible to all the herbicides tested. Timothy and foxtail barley were moderately tolerant while tall wheatgrass exhibited the greatest tolerance to flucarbazone. Orchardgrass was most tolerant to propoxycarbazone. Salinity tolerance was determined by exposing grasses to increasing electrical conductivity (EC) over time. Reed canarygrass and timothy were most susceptible to salinity. Orchardgrass, creeping foxtail, and tall fescue were moderately tolerant of salinity. Foxtail barley, altai wildrye, and tall wheatgrass exhibited the highest tolerances to salinity, and continued to persist at the highest EC levels tested. Flooding tolerance was determined by flooding grasses in 18 cm of water for 2, 4, 6, and 8 weeks. Grasses that were able to extend above the water surface survived, whereas plants that failed to extend beyond the water surface experienced higher mortality rates.
45

Effects of Recycled Water on Landscape Plants

Miranda, Casey R 01 June 2010 (has links) (PDF)
ABSTRACT EFFECTS OF RECYCLED WATER ON LANDSCAPE PLANTS Casey Ray Miranda Recycled water is water that has been previously used, has suffered a loss of quality, and has been properly treated for redistribution (Wu et al. 2001). The use of recycled water as an alternative to fresh water in the landscape can have positive and negative effects. Experimentation on 40 different plant species during a 32 week period (2 phases of 16 weeks), was conducted to analyze the effects of recycled water irrigation on the appearance of landscape plants. Each species of plant was planted into 10 individual number 2 pots and irrigated with recycled water daily. Media and water were tested for nutrients and other constituents. In phase I there were four different species of grasses and grass-like plants, five different perennials, five species of shrubs, and four annuals tested; while phase II tested four species of herbaceous perennials, eight different species of shrubs, six species of groundcovers, and four species of annuals. All tests were conducted at the Paso Robles Waste Water Treatment Plant. Of the grasses and grass like species Yucca spp. and Buchloe spp. performed best. Osteospermum fruticosum, Lavandula angustifolia, Rosmarinus officinalis, Phormium tenax, and Pennisetum setaceum had the best appearance of the herbaceous perennials tested. For the shrubs, Coprosma repens, Cistus purpureus, Dodonea viscosa, Eleagnus pungens, Baccharis pilularis, Ceanothus thysiflorus, Thuja orientalis, and Nerium oleander had the best appearance when irrigated with recycled water. The best annuals were Senecio cineraria, Antirrhinum majus, Primula spp., Viola spp., and Calendula officinalis. Of the groundcovers Heuchera spp., Lonicera japonica, Vinca major, Hedera helix, and Ceanothus griseus had the best results. From the experiment a list of tolerant and non-tolerant plants was compiled (Appendices 1 and 2). While many plants were capable of developing and growing normally, other plants were sensitive to recycled water irrigation. In order to prevent salt damage to plants and expand the use of recycled water, salt tolerance of landscape plant material must be identified (Niu et.al, 2006).
46

Efeitos da salinidade e da composiÃÃo iÃnica da Ãgua de irrigaÃÃo sobre o desenvolvimento de plantas de feijÃo-de-corda / Effects of salinity and ionic composition of the water irrigation on the development of cowpea plants [Vigna unguiculata(L.)].

Robson Alexsandro de Sousa 12 March 2007 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O uso de Ãgua de qualidade duvidosa na irrigaÃÃo pode ser prejudicial Ãs plantas. O objetivo deste trabalho foi avaliar os efeitos da salinidade e da composiÃÃo quÃmica da Ãgua de irrigaÃÃo sobre o crescimento, as trocas de gasosas, a nutriÃÃo mineral e os teores de solutos orgÃnicos em plantas de feijÃo-de-corda [Vigna unguiculata (L.) Walp.] cv. PitiÃba. As plantas foram cultivadas em vasos contendo 22 kg de areia lavada, sob condiÃÃes de casa de vegetaÃÃo, e submetidas a 4 diferentes condutividades elÃtricas da Ãgua de irrigaÃÃo (0,5; 1,5; 3,0 4,5 dS m-1), obtidas com sais de NaCl, CaCl2.2H2O e MgCl2.6H2O (A1), com sais de Na2SO4, CaCl2, MgCl2, Na2CO3, NaHCO3 (A2), ou somente com NaCl (A3). O delineamento experimental foi o inteiramente casualizado em esquema fatorial 3 x 4, com 5 repetiÃÃes. Durante a conduÃÃo do experimento mediu-se a taxa de transpiraÃÃo, taxa de fotossÃntese lÃquida, teores de clorofila e a condutÃncia estomÃtica, bem como se analisou a condutividade elÃtrica da Ãgua percolada e do substrato. As plantas foram coletadas com 48 dias apÃs o plantio, medindo-se a Ãrea foliar; e, as massas frescas e secas de folhas, caules e raÃzes. Determinaram-se, em laboratÃrio, nas folhas e caules, os teores de Na+, Cl-, K+, Ca2+, P, Cu, Fe, Mn e Zn; nas folhas foram determinados os teores de prolina, proteÃnas, carboidratos e N-aminossolÃveis. A salinidade afetou a produÃÃo de biomassa, o crescimento foliar e as trocas gasosas das plantas, porÃm, com pequena influÃncia da composiÃÃo da Ãgua sobre esses parÃmetros. No entanto, a composiÃÃo iÃnica da Ãgua de irrigaÃÃo influenciou os teores de nutrientes minerais, especialmente sobre os teores de micronutrientes. Por outro lado, nÃo foram observados relacionamentos significativos entre os teores dos solutos orgÃnicos analisados e os nÃveis de salinidade e a composiÃÃo quÃmica da Ãgua. A composiÃÃo quÃmica da Ãgua de irrigaÃÃo à relevante quando se pretende irrigar, pois o aporte de diferentes sais ao solo poderà influenciar especificamente na absorÃÃo de nutrientes minerais, com possÃveis repercussÃes negativas no metabolismo da planta e na sua produtividade. / The use of the inadequate water in irrigation can be prejudicial to the plants. The objective of this work was to evaluate the effect of salinity and chemical composition of irrigation water on plant growth, mineral nutrition, gas exchange, and organic solutes contents of cowpea plants [Vigna unguiculata (L.) Walp.]. Plants were cultivated in plastic pots, using 22 kg of soil at greenhouse conditions and subjected to four different salt stress concentrations (0.5; 1.5; 3.0; and 4.5 dS m-1) in irrigation water. These different salt concentrations were obtained by adding NaCl, CaCl2.2H2O and MgCl2.6H2O (A1), a mixture of chloride, sulphate, carbonates, and bi-carbonates salts (A2), or alone NaCl (A3). A completely randomized design, in a factorial arrangement (3 x 4), with five replicates was adopted. During the experimental period, the following responses were evaluated: transpiration rate, stomatal conductance, net photosynthesis, chlorophyll contents. After 48 days after sowing they were measured total leaf area and fresh and dry masses of leaves, stems and roots. The contents of inorganic (Na, Cl, K, Ca, P, Cu, Fe, Mn, and Zn) and organic (proline, protein, carbohydrates e N-amino soluble) solutes were also determined. The salinity of irrigation water caused reduction in the biomass production, leaf growth and gas exchange, but it was not observed effects of the chemical composition of water on these parameters. However, the ionic composition of irrigation water affected the contents of mineral nutrients, especially the contents of micronutrients. On the other hand, it was not found significant relationships between organic solutes contents and the levels of salinity or chemical composition of the water. The results suggest that chemical composition of irrigation water is an important factor, since it could affect mineral nutrients uptake, which can cause negative effects on plant metabolism and productivity.
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Biometric and physiological responses of bean inoculated with Dark septate endophytic fungi under salt stress / Biometria e respostas fisiolÃgicas de feijÃo-de-corda inoculado com fungos endofÃticos dark septate sob estresse salino

Gabriel Castro Farias 21 February 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / With the increasing of areas degraded by soil salinization process, is necessary to increase of agricultural investments to be able to reach a production acceptable. In order to reduce such inputs, studies of microorganisms involved in the production process are becoming more constant. The objective of this study was to evaluate the associations between endophytic fungi Dark Septate and cowpea plants when irrigated with water of different salinities, analyzing biometrics, gas exchange, nutrient content and accumulation of organic solutes in the leaves. Cowpea plants were grow in containers of five liters under greenhouse conditions and subjected to four different electrical conductivity of irrigations water (1.2; 2.2; 3.6; 5.0 dS m-1). Were used for the inoculation strains Bâ2 and 21W and treatments were as follows: F1 â plants that were not inoculated; F2 â plants inoculated with strains 21W and F3 â plants inoculated with strain Bâ2. during the experiment was measured gas exchange and at the end of the experiment the plant were collected and determinate the leaf area, shoot dry mass, root dry mass, concentration of the foliar nutrients and organic solutes, and was made the determination colonization of roots by the fungus. The salinity caused significant reductions in biomass, leaf area and leaf gas exchange, however, the presence of the endophytic fungi provided a large tolerance to the adverse effects of salinity. There was a larger accumulation of calcium, sodium, clore and phosphorus in cowpea leaves with increasing salinity and decrease in the leaves of nitrogen and potassium. The presence of the fungus in the plant provided a foliar phosphorus and nitrogen. / With the increasing of areas degraded by soil salinization process, is necessary to increase of agricultural investments to be able to reach a production acceptable. In order to reduce such inputs, studies of microorganisms involved in the production process are becoming more constant. The objective of this study was to evaluate the associations between endophytic fungi Dark Septate and cowpea plants when irrigated with water of different salinities, analyzing biometrics, gas exchange, nutrient content and accumulation of organic solutes in the leaves. Cowpea plants were grow in containers of five liters under greenhouse conditions and subjected to four different electrical conductivity of irrigations water (1.2; 2.2; 3.6; 5.0 dS m-1). Were used for the inoculation strains Bâ2 and 21W and treatments were as follows: F1 â plants that were not inoculated; F2 â plants inoculated with strains 21W and F3 â plants inoculated with strain Bâ2. during the experiment was measured gas exchange and at the end of the experiment the plant were collected and determinate the leaf area, shoot dry mass, root dry mass, concentration of the foliar nutrients and organic solutes, and was made the determination colonization of roots by the fungus. The salinity caused significant reductions in biomass, leaf area and leaf gas exchange, however, the presence of the endophytic fungi provided a large tolerance to the adverse effects of salinity. There was a larger accumulation of calcium, sodium, clore and phosphorus in cowpea leaves with increasing salinity and decrease in the leaves of nitrogen and potassium. The presence of the fungus in the plant provided a foliar phosphorus and nitrogen.
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The effect of compost and priming on the salt tolerance of bread wheat (Triticum aestivum L. cv. S-24 and cv. Slambo) during germination and early seedling establishment

Gadeh, H. M. January 2013 (has links)
Soil salinity and the arid climate in Libya are major constraints in agriculture and predominantly in foodstuff production which are limiting wheat production and yield. The effect of pre-sowing seed treatments with 50 mM of KCl, NaCl, CaCl2, and distilled water as hydropriming on germination and early seedling growth in two wheat (Triticum aestivum L.) cultivars S-24 (tolerant) and Slambo (untested before) under 0, 100, 200 and 300 mM NaCl concentrations was examined. CaCl2 was the only priming treatment that significantly improved the germination percentage, germination rate, and mean germination time in both cultivars under almost all NaCl concentrations. Thus, priming with CaCl2 was selected for further experiments. In the greenhouse, seeds primed with 50 mM of CaCl2 also improved the emergence percentage, emergence rate, shoot and root length, and fresh and dry weight of shoots and roots of both cultivars under all NaCl concentration except at 300 mM where the emergence was completely inhibited. The response of wheat cultivars to three compost treatments including cow manure compost (CC), greenwaste compost (GC) and 50:50 mixture (mix) between them and sand at percentage inclusions of 10 and 30 % by weight under 0, 100, 200, and 300 mM of NaCl was also investigated. Among all compost treatments, 30% GC and 30% mix were the best treatment and improved almost all growth parameters under salt stress, and 30% GC was also the only treatment that had any emergence at 300 mM NaCl. 30% GC and 30% mix were selected for further experiments. The effect of the combination of the selected priming agent (CaCl2) and the best two compost treatments (30% GC and 30% mix) on the emergence and early seedling growth of both cultivars was tested. The results showed that all the treatments enhanced plant growth parameters including seedling ion uptake in both cultivars, with preference to primed seeds sown in 30% GC. The treatments had the following order of the performance of both cultivars under salt stress. Primed seeds sown in 30% GC > unprimed seeds sown in 30% GC > primed seeds sown in 30% mix > unprimed seeds sown in 30% mix. This enhancement is possibly due to the provision of Ca2+ and / or the improvement in the availability of water as both of them were improved by the application of priming and compost.
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ANÃLISE DA TOLERÃNCIA Ã SALINIDADE EM PLANTAS DE SORGO, FEIJÃO-DE-CORDA E ALGODÃO / ANALYSIS OF SALINITY TOLERANCE IN SORGHUM, BEANS AND COTTON.

Carlos Henrique Carvalho de Sousa 14 February 2007 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O objetivo deste trabalho foi avaliar os teores e distribuiÃÃo de Ãons e alguns parÃmetros morfosiolÃgicos associados com a tolerÃncia à salinidade em plantas de sorgo, feijÃo-de-corda e algodÃo. As plantas foram cultivadas em vasos contendo 15 kg de areia lavada, em condiÃÃes de casa-de-vegetaÃÃo, e irrigadas com Ãguas com trÃs nÃveis de salinidade (0,5, 4,0 e 8,0 dS m-1). O experimento foi montado seguindo um delineamento inteiramente casualizado, com arranjo fatorial 3 x 3 (3 espÃcies x 3 nÃveis de salinidade), com quatro repetiÃÃes. Durante a conduÃÃo do experimento foram mensuradas a altura da planta e o consumo de Ãgua. ApÃs 42 dias do inÃcio dos tratamentos foram medidas> acÃmulo de sais na Ãgua drenada e no solo, a Ãrea foliar e a produÃÃo de matÃria seca de folhas, caules e raÃzes. Foram tambÃm determinados: a suculÃncia foliar, a massa especÃfica foliar, a partiÃÃo de carbono e os teores de Na+, Cl-, K+, Ca2+ e prolina. A aplicaÃÃo de Ãgua salina afetou a partiÃÃo de carbono, reduziu o crescimento e o consumo de Ãgua pelas plantas, e provocou acÃmulo de sais na Ãgua drenada e no solo. No entanto, as percentagens de extraÃÃo de sais foram baixas nas trÃs espÃcies, sendo maior em algodoeiro e menor em sorgo A tolerÃncia à salinidade foi avaliada atravÃs dos dados de crescimento, os quais confirmaram a maior sensibilidade do feijÃo-de-corda e a maior tolerÃncia do algodÃo. O algodÃo se diferenciou das duas outras espÃcies por apresentar maior acÃmulo e retenÃÃo de Na+ e Cl- nas raÃzes, maior acÃmulo desses Ãons nos limbos foliares, menores alteraÃÃes nos teores de K+ e aumento nos teores de prolina em resposta ao aumento da salinidade. O sorgo apresentou menores teores de Ãons potencialmente tÃxicos (Na+ + Cl-) nos limbos foliares, porÃm, apresentou reduÃÃes nos teores de K+ e Ca2+ na parte aÃrea. O elevado acÃmulo de Cl- nas folhas, associado à falta de outros mecanismos eficientes de proteÃÃo, contribuiu, pelo menos em parte, para a maior sensibilidade do feijÃo-de-corda ao estresse salino. / The objective of this paper was to evaluate ions concentration and some morphophysiological parameters associates to the salt tolerance in sorghum, cowpea, and cotton plants. Plants were cultivated in plastic pots, using 15 kg of sand soil at greenhouse conditions and subjected to three different salt concentrations (0.5; 4.0; and 8.0 dS.m-1) in irrigation water. A completely randomized design, in a factorial arrangement 3 x 3 (3 species x 3 salt levels), with four replicates was adopted. During the experimental period, plant height and water use was measured. After 42 days of salt application they were measured the salinity of drained water and in the soil, total leaf area and dry masses of leaves, stems and roots. Leaf succulence, specific leaf mass, carbon partitioning and the concentrations of Na, Cl, K, Ca, and proline were also determined. The application of saline water affected the carbon partitioning, reduced plant growth and water use, and caused salt accumulation in drained water and into the soil. However, the percentage of ion extraction from the soil was low in the three species, being higher in cotton and lower in sorghum. The tolerance index, on the basis of the growth data, confirmed the highest sensibility of the cowpea and the highest tolerance of the cotton. The cotton showed some important difference to the other species, presenting greater accumulation and retention of Na and Cl in the roots, greater accumulation of these ions in the leaf blades, lower changes in K concentration and increase in proline contents in response to sat stress application. On the other hand, sorghum showed lower concentrations of potentially toxic ions (Na plus Cl) in the leaf blades. However, it also presented reductions in K and Ca contents, what can contribute to growth inhibition in this species. The high leaf Cl concentration, associated with the absence of the other protection mechanisms, contributed, at least in part, to higher sensibility of the cowpea to salt stress imposed.
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Physiology, comparative genomics and germplasm development for improvement of salt tolerance in hexaploid wheat

Mullan, Daniel John January 2006 (has links)
[Truncated abstract] Lophopyrum elongatum, a wild relative of wheat, can be used as a source of novel genes for improving the salt tolerance of bread wheat. Na+ `exclusion? is a major physiological mechanism for salt tolerance in the wheat L. elongatum amphiploid, and a large proportion (~50%) of the improved Na+ `exclusion? is contributed by a gene(s) on chromosome 3E. This study integrated physiological analysis with comparative genomics to identify gene orthologues that may regulate Na+ transport, and designed and implemented molecular markers for developing wheat L. elongatum recombinant lines with reduced portions of L. elongatum chromatin retaining the Na+ `exclusion? trait. Physiological analysis of leaf Na+ accumulation in wheat L. elongatum substitution lines confirmed that the 3E chromosome contributes a major effect on reduced leaf Na+ accumulation in wheat when grown at 200 mM NaCl. Candidate genes from the model plant, Arabidopsis thaliana, controlling Na+ transport into and from cells (SOS1, HKT1) or compartmentalisation within vacuoles (NHX1, NHX5, AVP1, AVP2) were targeted for comparative analysis in wheat. Wheat gene orthologues were identified by BLAST searching to identify either FL-cDNAs or ESTs, which were subsequently used to amplify genomic DNA, and orthologues confirmed by similar intron-exon structure between Arabidopsis and rice. Intron-exon comparisons showed the majority of exons were conserved between Arabidopsis, rice and wheat, but also indicated exon shuffling events since divergence from a common ancestor. Gene orthologues were assigned to homoeologous chromosomes and non-syntenic regions between wheat and L. elongatum, with the SOS1 orthologue located on group 3 chromosomes in wheat and L. elongatum. ... The recombinant line 524-568 contains a small introgression on the distal end of the long arm of wheat chromosome 3A and represents the most desirable line presently available for further germplasm development. The main outcomes of this thesis have been an increased understanding of the physiology and evolution of orthologues for Na+ transport in wheat and L. elongatum, improved methodologies for designing alien-specific PCR markers, and the development of overlapping recombinant lines that provide a source of novel genes for pyramiding into wheat and improving its tolerance to salt stress.

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