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Herbert, Nick. "The mineral nutrition of heather on calcareous soil." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285878.
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Ericaceous plants grow preferentially on soils with a low pH, and generally perform poorly in areas with high pH calcareous soils. The reasons for the calcifuge behaviour of species of one genus, Erica, was studied in a calcareous rendzina collected from the South Downs, with a view to identifying physiological characteristics which could be used to select for improved lime-tolerance in the Ericaceae. Varieties of E. carnea and E. x darleyensis were shown to be relatively resistant to chalk-soil compared with varieties of E. vagans. In soil-based screening experiments, E. vagans 'Lyonesse' and 'Mrs D. F. Maxwell' rapidly developed severe foliar chlorosis, or lime-induced chlorosis, and their growth in soil was depressed by up to 7-fold compared with plants in an acid (pH 4) peat compost. E. carnea and E. x darleyensis varieties were resistant to chlorosis and remained green in chalk soil. The addition of nutrients (NPK and trace elements) increased the growth of the lime-resistant varieties in both peat and chalk soil. In nutrient solution, the source of nitrogen (nitrate or ammonium ions) had little effect on the growth of either lime-resistant or lime-sensitive varieties, although some varieties performed better when a component of the N was in the form of N03'. In an Fe-free nutrient solution, 1 mM NaHCO3 markedly reduced the root and shoot growth of both lime-tolerant and sensitive varieties. The clear differences between lime-resistant and lime-sensitive varieties found in soil experiments were not apparent with NaHCO3 in solution culture indicating that low concentrations of bicarbonate in nutrient solution may not be an appropriate method of screening for improved lime-tolerance in Erica. Bicarbonate and high pH in nutrient solution depressed the uptake of the radioisotopes 59Fe and 86Rb in both lime-resistant and lime-sensitive cultivars. Iron deficiency, induced by withholding Fe in nutrient solution, resulted in an elevated rate of root Fe(III)EDTA (ethylenediaminetetraacetic acid) reduction compared with Fesufficient plants. The maximum induced Fe(III)EDTA reduction rate (Vn,. ) of limeresistant cultivars (0.96-0.107 pmol. g"' FWT. h'') was lower than that of lime-sensitive varieties (0.125-0.404 tmol. g' FWT. h-1), suggesting that roots of lime-sensitive varieties have a greater capacity for Fe absorption than lime-tolerant varieties. Spraying or watering with Fe chelate (FeEDDHA - ethylenediamine di(ohydroxyphenylacetic acid)) remedied chlorosis in the lime-sensitive varieties and increased leaf chlorophyll by up to six fold and whole plant biomass by up to two fold. Chlorosis was associated with a reduced concentration of o-phenanthroline-extractable ('active') Fe, and a high concentration of total Fe, compared with green tissue. It is concluded that in chalk soil, lime-induced chlorosis, caused by the immobilisation of Fe in the shoot and a reduction in 'physiologically active' Fe in the leaf tissue, characterises lime-sensitive heather varieties. Resistance to chalk soil in Erica appears not to be related to root physiology. Rather the ability to transport and distribute Fe within the shoot under calcareous conditions is a major factor contributing to limeresistance in heathers.
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Coyle, Kieran. "An investigation of the role of soil micro-organisms in phosphorus mobilisation : a report submitted to fulfil the requrements of the degree of Doctor of Philosophy." Title page, table of contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phc8814.pdf.
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Kim, Hak Jin. "Ion-selective electrodes for simultaneous real-time analysis for soil macronutrients." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4471.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (April 26, 2007) Vita. Includes bibliographical references.
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Santos, Francisco SÃrgio Ribeiro dos. "Production and nutrition in strawberry crop soil and hydroponic." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13165.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorTraditional soil based strawberry production currently faces some obstacles, both by excessive use of pesticides, as the diseases caused by fungi and other pathogens and ergonomic difficulties of cultivating the soil. Strawberry soilless cultivation combined with greenhouse and the use of substrate promotes some advantages such as: eliminating the use of products for soil disinfection, precocity, increased yields, better crop management conditions and crop protection against adverse weather conditions, pest attacks and diseases.. The objective of the study was to evaluate yield and nutrition of four strawberry cultivars in three cropping systems in Serra da Ibiapaba â CearÃ. The experiment was conducted in 3 x 4 factorial design, randomized blocks, with three cultivation systems arranged in strips (soil, hydroponic in gutters and bags), with four strawberry cultivars (Oso Grande, Albion, and Camarosa and Festival) and five replications. Coconut fiber was used as substrate in the hydroponic systems. In the period between the sixth and thirty-eighth week after transplanting, the number and average fruit weight, yield per plant and yield were determined. From the beginning of flowering, leaves were collected every two months to determine the levels of macro and micronutrients. Hydroponic gutter and bag systems increased the number of fruits per plant, but did not increase average fruit weight. The strawberry yield in hydroponic cultivation system was superior to soil cultivation. Cultivar Festival presented more fruits than the other cultivars in hydroponic systems. The Oso Grande and Festival cultivars stood out as the average fruit weight and yield, respectively, and may be recommended for hydroponic cultivation for the region of Serra da Ibiapaba. Based on the leaf nutrient contents, it is suggested adjustments in concentrations of phosphorus and magnesium in the nutrient solution used in hydroponic strawberry crop. Keywords: Fragaria x ananassa, cultivar, nutrients, crop system,
O cultivo do morangueiro no solo enfrenta atualmente alguns entraves, tanto pelo uso excessivo de defensivos, como pelas doenÃas causadas por fungos e outros patÃgenos e as dificuldades ergonÃmicas do cultivo no solo. O cultivo em sistemas sem solo combinado com ambiente protegido e o uso de substrato proporciona algumas vantagens como: eliminaÃÃo do uso de produtos destinados à desinfecÃÃo do solo, antecipaÃÃo do inÃcio das colheitas, aumento da produÃÃo, proteÃÃo da cultura Ãs condiÃÃes meteorolÃgicas adversas, ataque de pragas e doenÃas e melhores condiÃÃes de manejo da cultura. O experimento teve como objetivo avaliar a produÃÃo e nutriÃÃo de quatro cultivares de morango em trÃs sistemas de cultivo na Serra da Ibiapaba â CearÃ. O experimento foi conduzido em esquema fatorial 3 x 4, em blocos casualizados, sendo trÃs sistemas de cultivo dispostos em faixa (solo, hidropÃnico em calhas e em s a c o l a s ), com quatro cultivares de morangueiro (Oso Grande, Albion, Camarosa e Festival), com cinco repetiÃÃes. No sistema hidropÃnico foi utilizado como substrato fibra de coco. No perÃodo entre a sexta e trigÃsima oitava semana apÃs o transplantio, foi determinado o nÃmero e peso mÃdio de frutos, produÃÃo por planta e produtividade. A partir do inÃcio do florescimento, foram coletadas a cada dois meses folhas para determinaÃÃo dos teores de macro e micronutrientes. Os sistemas hidropÃnicos em calha e em sacolas aumentaram o nÃmero de frutos por planta, porÃm nÃo aumentaram o peso mÃdio de frutos. A produtividade do morangueiro cultivado no sistema hidropÃnico foi superior ao cultivo no solo. A cultivar Festival apresentou maior nÃmero de frutos em relaÃÃo as demais cultivares nos sistemas hidropÃnicos. As cultivares Oso Grande e Festival destacaram-se quanto a peso mÃdio de frutos e produtividade, respectivamente, sendo recomendadas para cultivo hidropÃnico para regiÃo da Serra da Ibiapaba. Com base nos teores de nutirentes na folha sugere-se ajustes nas concentraÃÃes de fÃsforo e magnÃsio na soluÃÃo nutritiva utilizada no cultivo hidropÃnico do morangueiro. Palavras-chaves: Fragaria x ananassa, cultivar, sistema de cultivo, nutrientes.
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Yeap, Simon Guo Hong. "Implications of soil water repellence for crop growth and nutrition." Thesis, Yeap, Simon Guo Hong (2020) Implications of soil water repellence for crop growth and nutrition. PhD thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/59040/.
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In water-limited environments, dryland crop and pasture production on water-repellent sandy soils is often constrained by reduced water infiltration, accentuated overland flow and soil erosion, unstable wetting patterns, and the development of preferential flow paths in the soil profile, which consequently cause considerable spatial heterogeneity in soil water content, increased prevalence of isolated dry zones, and decreased overall soil water retention. The same processes are also likely to affect soil nutrient bioavailability and plant nutrient uptake. Indeed, while problems with crop nutrition on water-repellent sandy soils have been reported by many Australian growers, the role of soil water repellence in crop nutrition has not been studied to date and the mechanisms remain unclear. While various methods exist to manage soil water repellence for improving crop and pasture production (e.g., deep soil cultivation, clay spreading, wetting agent application, stimulation of wax-degrading microorganisms, furrow/on-row sowing and water harvesting, and no-tillage and stubble retention), the outcomes for crop nutrition post-amelioration are not well understood.
Several field and glasshouse experiments were, therefore, conducted to assess the implications of soil water repellence and its management on crop growth and nutrition on several sandy soil types from the southwest region of Western Australia. Preliminary field results showed that soil water repellence, if left unmanaged, could adversely affect wheat plant density, shoot dry matter production, K nutrition, and grain yield on a Grey Bleached-Ferric Kandosol (deep grey sandy duplex soil) at Meckering with a moderate water repellence value of up to 1.6 M using the molarity of ethanol droplet (MED) test, supporting the hypothesis that soil water repellence can adversely affect crop growth, nutrition, and grain production. However, it was also revealed at another site, with a Ferric Chromosol (sandy loam yellow duplex soil) at Kojonup, that increased soil water repellence could also increase canola plant density, shoot dry matter production, Cu nutrition, and seed yield when sown with 1 L/ha of banded wetting agent, despite prolonged severe water repellence (MED of 3.4 M) throughout the growing season. Although the underlying mechanisms could not be established from this preliminary study, it was concluded that soil water repellence may have both adverse and beneficial implications, but specific effects on nutrient availability in the root zone and crop nutrition were not defined.
Additional field studies were conducted to assess the effect of soil management practices (spading, one-way plough, subsoil clay spreading, and blanket applications of wetting agent) to alleviate soil water repellence on crop growth and nutrition. While all treatments except for one-way ploughing alleviated soil water repellence, only spading significantly improved wheat emergence, shoot dry matter, K nutrition, and grain yield on a Grey Tenosol (pale deep sandy soil) at Badgingarra. By contrast, at Moora, one-way plough treatments improved canola shoot dry matter and nutrition (Ca, S, B, Cu, and Zn contents) but did not mitigate severe water-repellence on a Ferric Chromosol (sandy ironstone gravel duplex soil), and had no effect on plant density or seed yield. However, the improvements due to soil cultivation can be attributed to the alleviation of soil compaction, given that the alleviation of soil water repellence by blanket-applied wetting agent (50 L/ha) and subsoil clay spreading treatments (250 t/ha; 50 % clay; 159 mg K/kg) had negligible effect on crop growth, nutrition, and grain production. Alleviation of soil water repellence was, therefore, not important for crop production at the Badgingarra and Moora study sites, presumably due to the presence of other soil constraints.
To avoid the confounding effects from multiple limiting factors evident in the field studies, a series of controlled glasshouse experiments were conducted to examine the effects of topsoil water repellence, topsoil thickness, fertiliser placement, variable low water supply, plant density, and/or surface topography on soil water content, soil nutrient availability, and early wheat growth and nutrition in 27 L containers. All glasshouse experiments demonstrated that severely water-repellent topsoil with a wettable furrow, which ensured uniform seedling emergence, significantly increased wheat seedling development, tiller number, shoot dry matter production, and nutrition (especially N, P, and K) during the early vegetative stage in wheat (40-51 DAS), under low but regular water supply (3.4-5.4 mm every two days). The growth stimulation was attributed to in situ water harvesting caused by preferential flow in the wettable furrow which increased the soil wetting and root depth relative to the completely wettable topsoil treatments that exhibited an even but shallow wetting depth. The even but shallow wetting patterns in completely wettable treatments consequently led to an overall decrease in plant-available water and plant water use efficiency, resulting in poor wheat growth and nutrition, especially under a limited water supply. These findings underscore the high efficacy of in situ water harvesting for improving early wheat growth and nutrition on water-repellent soils relative to completely wettable soils, thus demonstrating a beneficial role of soil water repellence in crop growth and nutrition. Adopting in situ water harvesting principles (i.e., furrow sowing, banding wetting agent in the furrow, and using winged knife-points and/or press-wheels) can, therefore, be an effective strategy for managing crop growth and nutrition on water-repellent sandy soils by maximising the use efficiency of limited soil water supply during the crop establishment period.
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Strömgren, Monika. "Soil-surface CO₂ flux and growth in a boreal Norway spruce stand : effects of soil warming and nutrition /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6304-1.pdf.
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Gosling, Paul. "The role of tree lupin (Lupinus arboreus, sims) in primary succession, with particular reference to phosphorus." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320630.
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Martinez-Sanchez, Jose Luis. "Aspects of rain forest nutrition dynamics at Los Tuxtlas, Mexico." Thesis, University of Stirling, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311704.
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Kering, Maru K. Blevins Dale G. "Manganese nutrition and photosynthesis in NAD-malic enzyme C-4 plants." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/7201.
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Title from PDF of title page (University of Missouri--Columbia, viewed on February 24, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Dale Blevins. Vita. Includes bibliographical references.
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Su, Jinghan. "Nitrogen fertilization and soil mineral nitrogen dynamics to optimize canola yield and nutrition in Québec." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117231.
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Canola is an ideal feedstock for biodiesel production because of its high oil and low saturated fat concentrations. There is interest in producing more canola in Québec, but producers lack fertilization guidelines to optimize high oilseed yield and quality in canola. Nitrogen (N) is the most important determinate of oilseed yield and quality and N fertilization is important for biomass accumulation during the early vegetative stage and for oil synthesis during the reproductive stage. The first objective of this study was to monitor soil mineral N (NO3-N + NH4-N) dynamics and canola straw nutrition in response to N fertilization. Two fertilization methods - a pre-plant and split application of fertilizer N were studied at the Emile A. Lods Agronomy Research Centre on the Macdonald Campus of McGill University at Ste-Anne-de-Bellevue, Québec, using a fractional factorial experimental design. The second objective was to evaluate N use efficiency (NUE) and harvest index (HI) of canola grown in pots containing soils from Ste-Anne-de-Bellevue, St-Augustin-de-Desmaures and Ottawa using a completely randomized design. Split application of a sidedressed N fertilizer did not increase the post-harvest soil mineral N concentration or increase straw nutrition compared with the pre-plant N application. There was considerable spatio-temporal heterogeneity in soil mineral N dynamics, so additional field trials are warranted. The pot study showed inconsistent correlations between straw N concentration and yield in canola grown in the soils collected from Ste-Anne-de-Bellevue (not related), St-Augustin-de-Desmaures (negative), and Ottawa (positive). Straw N concentrations were related to low straw and oilseed yield, indicating there is an optimal straw N concentration to achieve target yields. Seeding in late May and disease occurrence close to the end of flowering stage reduced the oilseed yield more than straw yield. Future research on the pattern of N translocation (e.g.: from leaf to pod, then to oilseed) under Québec climatic conditions will contribute to the development of an N fertilization guideline. Since some soils in Québec have an appreciable soil N supply, knowledge of how much soil N is used to meet canola N requirement will keep N fertilizer costs low while optimizing oilseed yield and quality.Le canola est une matière première idéale pour la production de biocarburant car il a une teneur élevée en huile et basse en gras saturés. Au Québec, les producteurs sont intéressés à cultiver davantage de canola, mais font face à un manque de directives en matière d'engrais nécessaire afin d'obtenir un haut rendement d'huile de qualité à partir du canola. L'azote (N) est chez les oléagineux le facteur le plus important déterminant le rendement et la qualité de l'huile; l'engrais azoté est important pour l'accumulation de biomasse pendant le premier stade végétatif et pour la production d'huile pendant le stade reproductif. Le premier objectif de la présente étude a été de suivre l'évolution de la dynamique de l'azote minéral du sol (NO3-N + NH4-N) et la nutrition de la paille de canola en réponse à l'engrais azoté. Deux méthodes de fertilisation – fertilisation en présemis et fertilisation partagée fractionnée ont été étudiées au Centre de recherche agronomique Emile A. Lods, au campus Macdonald de l'université McGill à Ste-Anne-de-Bellevue, Québec, utilisant un plan d'expérience factoriel fractionnel. Le deuxième objectif a été d'évaluer l'efficacité d'utilisation de l'azote (NUE) et l'indice de récolte (HI) du canola cultivé en pots avec du sol provenant de Ste-Anne-de-Bellevue, de St-Augustin-de-Desmaures et d'Ottawa, utilisant un plan d'expérience entièrement aléatoire (conception de bloc complètement randomisé). La fertilisation fractionnée et l'application d'azote en bande avec de l'engrais azoté de couverture n'a pas augmenté la concentration d'azote minéral du sol après-récolte, ni la nutrition de la paille de canola comparativement à la fertilisation azotée précoce (see correction above for précoce). Dû à l'importante hétérogénéité spatio-temporelle de la dynamique de l'azote minéral du sol, des études sur le terrain additionnelles sont à recommander. L'étude des plants en pots a démontré une corrélation linéaire négative entre la concentration en azote de la paille et le rendement de la paille. Les concentrations en azote de la paille ont été corrélées avec des bas rendements de paille et d'huile, indiquant qu'il existerait une concentration idéale de l'azote de paille pour obtenir les rendements visés. Certains facteurs réduisent la qualité de l'huile ainsi que le rendement de la paille, soit de semer vers la fin mai ainsi que les maladies qui apparaissent lors de la floraison. D'autres études sur la translocation de l'azote (p. ex. de la feuille à la gousse, puis à la graine) sous les conditions climatiques du Québec contribueront au développement des directives en matière de fertilisation azotée. Puisque certains sols du Québec ont des réserves appréciables d'azote du sol, connaître la quantité d'azote du sol nécessaire afin de satisfaire aux besoins en azote du canola permettra de maintenir de bas coûts pour l'engrais azoté, ainsi que d'optimiser le rendement et la qualité de l'huile des oléagineux.
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Brebner, Jocelyn. "The role of soil ingestion in the trace element nutrition of grazing livestock." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38242.
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Schalau, Jeff W. "Laboratories Conducting Soil, Plant, Feed, or Water Testing." College of Agriculture, University of Arizona (Tucson, AZ), 2016. http://hdl.handle.net/10150/625536.
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Walsh, Brice D. (Brice David). "Mulch management systems in organic dwarf apple orchards and their effects on soil physical properties, soil nutrient availability, and tree nutrition." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55402.
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An alternative to herbicides in dwarf apple orchards (Malus pumila Mill.) is the use of mulches. Research objectives were to compare several mulch systems (Festuca rubra L., Lupinus albus L. plus Daucus carota L.; straw, manure compost, geotextile) with soil cultivation as to soil physical properties and plant nutrient levels in soils, leaves and fruit. Studies carried out in 1992 and 1993 on three dwarf apple orchards on the Macdonald Campus of McGill University showed that straw mulch increased soil water contents and exchangeable K, but reduced exchangeable Mg compared to Festuca mulch. Straw mulch reduced soil temperatures in summer relative to geotextile or cultivation. Festuca reduced leaf N contents but increased leaf P contents-elative to geotextile treatments. Soil nitrate N contents were correlated with soil water contents, and the ratios N/Ca and K/Ca in the fruit were unaffected by treatment. Straw and geotextile mulches increased soil water content and nitrate-N levels during peak sowing periods and thus were the superior treatments.
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Costa, Claudio Hideo Martins da [UNESP]. "Efeito residual da aplicação superficial de calcário e gesso nas culturas de soja, aveia-preta e sorgo granífero." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/86428.
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000678831.pdf: 1444305 bytes, checksum: d3e614871d6cd55de66eda01f9f2bdd0 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
No sistema plantio direto praticamente não há revolvimento do solo e o consequente acúmulo de fertilizantes na superfície acelera o processo de acidificação, contínuo e acentuado que ocorre naturalmente em solos de regiões úmidas, onde, geralmente, é observada baixa disponibilidade de nutrientes e elevados teores de alumínio. Assim, da mesma forma que no sistema de cultivo convencional, no sistema plantio direto também existe a necessidade de aplicação de insumos em superfície, especialmente, materiais corretivos de acidez. Dentro deste enfoque, o trabalho foi desenvolvido na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas – UNESP, Campus de Botucatu (SP), dando continuidade a um projeto de pesquisa que vem sendo conduzido desde 2002, com o objetivo de avaliar o efeito residual da aplicação superficial de corretivos na correção da acidez do solo, bem como na nutrição, na produtividade das culturas da soja e do sorgo e na produção de matéria seca e acúmulo de nutrientes da aveia-preta em região de inverno seco. O delineamento experimental utilizado foi em blocos casualizados em parcelas subdivididas, com 4 repetições. As parcelas foram constituídas por quatro doses de calcário (0, 1000, 2000 e 4000 kg ha-1) e as subparcelas por duas doses de gesso agrícola (0 e 2100 kg ha-1), aplicado em novembro 2004. Como cultura de verão foi utilizada a cultura da soja e na entressafra as culturas da aveia-preta e sorgo granífero. A aplicação de calcário em superfície promoveu diminuição da acidez e elevação nos teores de fósforo, cálcio, magnésio e matéria orgânica, em praticamente todo perfil do solo. A aplicação de gesso agrícola promoveu aumentos nos 2 teores de Ca trocável e S-SO42-, e diminuição no teor de Al trocável no solo...
In no tillage system the absence of soil mobilization consequently decreases places fertilizers on surface, affecting the acidification process. Like in conventional system, in no tillage it is also necessary input application, especially materials for acidity correction. The experiment was carried out in an experimental area, in the city of Botucatu (SP, Brazil), continuing a research project that has been conducted since 2002, to evaluate the long-term effects of surface application of lime and gypsum on acidity correction, nutrition, yield of soybean and sorghum, and dry matter production and nutrients accumulation on black oat in a dry winter region. The experimental design was the completely randomized with subdivided plots and four replications. The mains plots consisted of four dolomite limestone levels (0, 1000, 2000 e 4000 kg ha-1) and the subplots consisted areas with and without gypsum (0 and 2100 kg ha-1), applied in November 2004. Soybean was the summer crops and the off-season crops are black oat and grain sorghum Lime surface application reduced soil acidity and increased phosphorus, calcium, magnesium and organic matter, practically all the soil profile. Phosphogypsum application promoted increasing exchangeable Ca and S-SO42- contents, and decreased exchangeable Al in the soil, favoring the effects of surface liming on soil properties, mainly the surface layer (0-0.20 m). Base saturation values obtained at a depth of 0-0.20 m with liming were lower than those estimated by BS method, even with phosphogypsum application. Liming increased, on soybeans, foliar contents of N, P, Ca, Mg and S in 2008/09, and N, Ca and Mg, in 2009/10. In the presence of phosphogypsum increased the levels of N In no tillage system the absence of soil mobilization consequently... (Complete abstract click electronic access below)
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Li, Maolin. "Adsorption characteristics and dynamics of soil organic phosphorus and its significance for plant nutrition /." Beuren ; Stuttgart : Grauer, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009665345&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Tariq, Mohammad. "Effect of boron supply on the availability of nutrients in soil and uptake by radish (Raphanus sativus L.)." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363708.
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Cruz, David Ricardo Jimenez. "Influence of soils, nutrition, and water relations upon charcoal rot disease processes in Kansas." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/10747.
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Master of ScienceDepartment of Plant Pathology
Christopher R. Little
Christopher R. Little
Charcoal rot, caused by Macrophomina phaseolina, is the most important soybean disease in Kansas. Several strategies have been recommended to control this disease including crop rotation, lower plant densities, biological control, plant resistance and tolerance, and fungicide application. However, those techniques have not been completely effective and the information concerning soil texture, irrigation and micronutrient fertility (particularly manganese) upon charcoal rot disease severity and the pathogen population is limited. The objective of this study was to determine key factors that affect the biology of M. phaseolina and charcoal rot processes under laboratory, greenhouse and field conditions. M. phaseolina microsclerotia were produced from PDA pure isolate and infested Japanese millet in the laboratory and characterized by different techniques such as serial dilutions in semi selective media with the aim to produce quality inoculum to reliably infect soybean seedling roots under greenhouse conditions; production of inoculum by infesting Japanese millet was the most efficient method. Root colonization and root infection of soybean seedlings was assessed through the use of M. phaseolina inoculum under controlled conditions in the greenhouse. Root infection by M. phaseolina and microsclerotia longevity in soil is determined by environmental factors such as soil moisture content, soil texture and source of inoculum. The objective of the greenhouse study was to determine the impact of these variables on seedling root infection at the V1 and V2 development stages. Artificial soils with different textures were infested; M. phaseolina microsclerotia and soybean seedlings were exposed to different soil moisture contents including pot saturation, pot (field) capacity, and permanent wilting point. Soil populations and levels of root colonization for the stages were assessed by estimating CFUs and root length. Results indicate that soil texture has a significant impact upon root morphology and root length. Root populations of M. phaseolina were significantly higher in sandy soil textures and lower in the fine-textured soils, suggesting an impact of soil water holding capacity in the root infection process. The effect of water stress on seedling root colonization by M. phaseolina indicates that early infection may be more important than previously thought. A field study was also conducted to determine the effect of the aforementioned variables in a 2-year field experiment conducted at two Kansas locations. Pathogen colonization was iii assessed by measuring colony-forming units (CFUs) from ground root tissue at R2-R4 (post-flowering/early pod development) and R8 (maturity) stages. Soil populations (pre-planting and post-harvest) of M. phaseolina, yield parameters, and plant characteristics were obtained. Results indicated that there are complex relationships between soil physiochemical properties (pH, NPK content, exchangeable cations, and organic matter) and soil texture (sand, soil, and clay composition), which may mitigate disease severity and pathogen levels in host tissue. Results also indicated that in natural M. phaseolina-infested soils, cropping history and soil texture play an important role in charcoal rot processes and influence the levels of pathogen soil populations, root colonization at maturity and, more importantly, soybean yield.
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Alloush, Ghiath Ahmad. "The mechanism of mobilization of iron from soil minerals in the rhizosphere of Cicer arietinum L." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277495.
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Landry, Christine. "Phosphorus fertilization and mycorrhizae influence soil phosphorus dynamics, corn nutrition and yield under reduced-tillage practices." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115705.
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Grain corn (Zea mays L.) production occupies more farmland than any other annual crop in Quebec and is expanding demand from the livestock sector and the emerging bioethanol industry. Corn production requires high nutrient inputs and intensive tillage (IT). Many producers have thus switched to conservation tillage systems like ridge-tillage (RT) to overcome soil compaction and erosion problems that are common in IT systems. However, fertilizer guidelines developed for IT soils are used in RT although RT adoption greatly modifies phosphorus (P) dynamics. Lower fertilizer P requirements are expected because arbuscular mycorrhizal (AM) symbiosis known to enhance plant P nutrition are minimally disrupted under RT, compared to IT systems. A two-year study was conducted on a commercial farm in the Monteregie region (Quebec, Canada) to investigate the effects of P fertilizer rates and soil P-saturation status on corn early growth, nutrition and yield. Surface soil plant-available P was monitored in situ with anionic exchange membranes (P AEM) from seeding to the end of July. The effects of indigenous AM fungi on corn parameters and rhizosphere soil P pools were also investigated in untreated (AMNI) or AM-inhibited fungicide-treated (AMI) soils. Quebec's P fertilizer guidelines underestimated the soil P fertility in studied soils. Adding inorganic P (Pi) did not improve the early corn P nutrition, growth or yield, and had little impact soil PAEM. Variations in PAEM were better explained by climatic variables. AMNI corn had similar early development and high yield, regardless of whether P fertilizer was applied, whereas AMI plants needed P fertilizer to produce optimal yield. AMNI corn had reduced dependence on Pi inputs due to more efficient uptake of soil solution P i in surface and rhizosphere soils during the first 22 days after seeding (DAS), In the rhizosphere, available-Pi pool appeared to be used first to replenish the resin-P pool, but over the longer term, AM symbiosis also enhanced NaHCO3-Po mobilization through a mechanism that remains unclear. Deeper understanding of the mechanisms by which AM fungi alter soil P dynamics will contribute to the development of more sustainable P fertilizer programs for RT systems.
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Kinsey, Graham. "The nutrition of the uninucleate trophic phase of soil-inhabiting myxomycetes in relation to their ecology." Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520282.
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Singbo, Arnaud. "The effect of zinc and soil ph on grain yield and nutrient concentrations in spring wheat cultivated on potted soil." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2845.
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Thesis (MTech (Agriculture))--Cape Peninsula University of Technology, 2018.Zinc deficiency on various soil types have been reported in arable soils of sub Saharan Africa (SSA) including South Africa. A pot trial was conducted at the Cape Peninsula University of Technology, Wellington campus to investigate the interaction of different application rates of Zn at various soil pH on the grain yield and quality of spring wheat in a completely randomized factorial design replicated three times. The four soil pH tested were: pHA: 5.1, pHB: 5.6, pHC: 6.1, pHD: 6.6 which correspond to lime application at 0, 0.5, 1 and 1.5 t/ha. Five Zn rates (Zn1: 3.5; Zn2: 4.5; Zn3: 5.5 Zn4: 6.5, and Zn5: 7.5 mg /kg soil which correspond to Zn1: 7; Zn2: 9; Zn3: 11; Zn4: 13 and Zn5: 15 kg /ha) were applied at two (planting and flowering) growth stages. Yield and yield component data collected were analyzed using SAS version 9.2 and means were separated by Duncun’s Multiple Range Test (DMRT). The results showed that grain yield and yield components were significantly affected by lime application pHC (6.1): 1t/ha at planting. Zn application at planting had no significant effect on the grain yield and yield components. However, at flowering, the simultaneous increase of Zn along with increase in lime positively affected grain yield and yield components. Plant analysis showed that at both stages (planting and flowering), Zn application, especially at pH 6.6, significantly increased P, K, Ca, Na, Mg Fe, Cu and B concentrations in wheat grain, but the concentrations of N, Mn, Zn and protein remained unaffected. Zn application had no effect on most nutrients due to the presence of lime. While the absence of lime, Zn4: 6.5mg/kg (corresponding to 13kg/ha) significantly increased the nutrients. In addition, Zn3: 5.5mg/kg (corresponding to 11kg/ha) promoted Zn absorption by grain in all treatments.
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Johnson, David. "Soil microbial biomass and activity and plant nutrition in semi-natural ecosystems subjected to pollutant nitrogen deposition." Thesis, University of Sheffield, 1998. http://etheses.whiterose.ac.uk/15149/.
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The response of UK semi-natural soil and plant communities to long-term inputs of pollutant nitrogen (N) is presently poorly understood. This study aims to investigate the effects of up to 8 years simulated pollutant N additions on plant nutrition and key below ground nutrient cycling processes in an upland heath, an acid grassland and a calcareous grassland. An additional series of plots was established in the grasslands that received short-term N and phosphorus (P) inputs which enabled investigation of NIP interactions and the determination of plant biomass. Soil inorganic N concentrations indicated that all of the sites had become 'N saturated', and that P limitation may be of increasing importance, particularly in the heathland and calcareous grassland. This was confirmed in the calcareous grassland where significant increases in above ground biomass were seen in only P treated plots, while in the acid grassland, there were no growth responses to nutrient additions. A field-based bioassay was developed which demonstrated that both short and long-term inputs of N significantly increased root surface phosphomonoesterase (PME) activity of Plantago lanceolata seedlings. A parallel microcosm-based bioassay revealed a significant relationship between root surface PME activity of Agrostis capillaris and extractable NfLt concentrations (r = 0.86) in the long-term acid grassland plots, indicating that this site may have reached or be approaching N saturation. In response to long-term N additions, soil microbial biomass carbon increased in the heathland, decreased in the acid grassland and remained constant in the calcareous grassland. Chloroform fumigation indicated that microbial biomass P decreased in the acid and calcareous grasslands, while microbial biomass N increased in the heathland and acid grassland in the N treated plots. Soil PME activity was highly sensitive to the N treatments. It increased at all sites and was significantly correlated with extractable inorganic N concentrations (r = 0.71) in the calcareous grassland, indicating close coupling between N saturation and P limitation. This relationship was also seen in the heathland where there was increased utilisation of monoester P sources in standard and customised BIOLOG plates and increased respiration rates in soils amended with organic P compounds. The implications of these results are discussed, with reference to the critical loads concept and to recent research by other workers in similar and contrasting environments.
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Ankrom, Katharine Elizabeth. "Identification of a new nematode species in Ohio and soil factor effects on plant nutrition of soybean." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1468842700.
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Costa, Claudio Hideo Martins da 1985. "Efeito residual da aplicação superficial de calcário e gesso nas culturas de soja, aveia-preta e sorgo granífero /." Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/86428.
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Orientador: Carlos Alexandre Costa CrusciolBanca: José Salvador Simoneti Foloni
Banca: Eduardo Fávero Caires
Resumo: No sistema plantio direto praticamente não há revolvimento do solo e o consequente acúmulo de fertilizantes na superfície acelera o processo de acidificação, contínuo e acentuado que ocorre naturalmente em solos de regiões úmidas, onde, geralmente, é observada baixa disponibilidade de nutrientes e elevados teores de alumínio. Assim, da mesma forma que no sistema de cultivo convencional, no sistema plantio direto também existe a necessidade de aplicação de insumos em superfície, especialmente, materiais corretivos de acidez. Dentro deste enfoque, o trabalho foi desenvolvido na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas - UNESP, Campus de Botucatu (SP), dando continuidade a um projeto de pesquisa que vem sendo conduzido desde 2002, com o objetivo de avaliar o efeito residual da aplicação superficial de corretivos na correção da acidez do solo, bem como na nutrição, na produtividade das culturas da soja e do sorgo e na produção de matéria seca e acúmulo de nutrientes da aveia-preta em região de inverno seco. O delineamento experimental utilizado foi em blocos casualizados em parcelas subdivididas, com 4 repetições. As parcelas foram constituídas por quatro doses de calcário (0, 1000, 2000 e 4000 kg ha-1) e as subparcelas por duas doses de gesso agrícola (0 e 2100 kg ha-1), aplicado em novembro 2004. Como cultura de verão foi utilizada a cultura da soja e na entressafra as culturas da aveia-preta e sorgo granífero. A aplicação de calcário em superfície promoveu diminuição da acidez e elevação nos teores de fósforo, cálcio, magnésio e matéria orgânica, em praticamente todo perfil do solo. A aplicação de gesso agrícola promoveu aumentos nos 2 teores de Ca trocável e S-SO42-, e diminuição no teor de Al trocável no solo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In no tillage system the absence of soil mobilization consequently decreases places fertilizers on surface, affecting the acidification process. Like in conventional system, in no tillage it is also necessary input application, especially materials for acidity correction. The experiment was carried out in an experimental area, in the city of Botucatu (SP, Brazil), continuing a research project that has been conducted since 2002, to evaluate the long-term effects of surface application of lime and gypsum on acidity correction, nutrition, yield of soybean and sorghum, and dry matter production and nutrients accumulation on black oat in a dry winter region. The experimental design was the completely randomized with subdivided plots and four replications. The mains plots consisted of four dolomite limestone levels (0, 1000, 2000 e 4000 kg ha-1) and the subplots consisted areas with and without gypsum (0 and 2100 kg ha-1), applied in November 2004. Soybean was the summer crops and the off-season crops are black oat and grain sorghum Lime surface application reduced soil acidity and increased phosphorus, calcium, magnesium and organic matter, practically all the soil profile. Phosphogypsum application promoted increasing exchangeable Ca and S-SO42- contents, and decreased exchangeable Al in the soil, favoring the effects of surface liming on soil properties, mainly the surface layer (0-0.20 m). Base saturation values obtained at a depth of 0-0.20 m with liming were lower than those estimated by BS method, even with phosphogypsum application. Liming increased, on soybeans, foliar contents of N, P, Ca, Mg and S in 2008/09, and N, Ca and Mg, in 2009/10. In the presence of phosphogypsum increased the levels of N In no tillage system the absence of soil mobilization consequently... (Complete abstract click electronic access below)
Mestre
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Frakes, Mitchell Laura Ann. "BORON NUTRITION OF BURLEY AND DARK TOBACCO." UKnowledge, 2014. http://uknowledge.uky.edu/pss_etds/51.
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The incidences of suspected Boron (B) deficiency have increased recently in Kentucky tobacco fields, potentially due to recent changes in management practices. The symptoms observed in the field include; hollow stalk, stunted growth, deformed or no bud formation, small slits on the lower leaf midrib and uncontrollable breaking of the midrib approximately two inches from the stalk. B is a micronutrient tobacco needs in minute amounts, however excessive additions of B could cause toxicity. The objectives of this work were to 1) establish critical points for B sufficiency, 2) describe and define B deficiency and toxicity symptoms and 3) develop field strategies to aid in the mitigation of B deficiency. A general nutrient response curve was generated utilizing solution culture experiments. The peak of the response curve appeared to occur at solution B concentration of 100 µM. Trace-levels of B contamination and small plant size in the solution culture limited the development of deficiency symptoms. Toxicity was observed at solution concentrations of 400 µM and above. Despite choosing sites with a history of B deficiency, deficiency symptoms were not observed during this study. Toxicity was observed when 0.56 kg B/ha or greater was applied as simulated transplant water treatments. No toxicity was observed when B was applied as a soil broadcast or foliar application. Recommendations are to apply B with caution as a broadcast application to avoid potential problems with toxicity. Additional research is required to refine the nutrient response curve and better understand B deficiency.
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Cottes, Jeremy Jean-Guy. "Le couple Eh/pH du sol : sa mesure, son impact sur la mobilité des nutriments et la croissance du tournesol." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0079.
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Ce travail de thèse s’inscrit dans un contexte d’agriculture durable qui vise à consommer de moins en moins d’intrants tout en maintenant des niveaux de production de biomasse croissante, aussi bien en termes de quantité que de qualité. De tels niveaux ne peuvent être atteints qu’à la condition que les végétaux cultivés puissent se développer dans des conditions optimales, et notamment avoir accès aux éléments minéraux essentiels à leur croissance. De nombreux facteurs interviennent dans la mise à disposition des nutriments présents dans le sol pour les cultures comme le pH ou le potentiel d’oxydo-réduction (Eh). Plusieurs auteurs ont montré que les plantes fonctionnaient au sein d’une gamme interne Eh/pH bien spécifique et qu’elles ont la capacité de modifier ces paramètres dans la rhizosphère pour assurer l’homéostasie intracellulaire. Cette étude a pour objectif final de contribuer à la compréhension des effets du potentiel redox du sol sur la mobilité et la mise à disposition des nutriments pour la plante. La difficulté réside dans la nécessité de réaliser les mesures aussi bien pour le Eh que le pH, in situ dans le sol et en présence de plantes. Bien que connaître le Eh sol soit essentiel, sa mesure reste complexe en raison du manque de fiabilité des protocoles proposés, de l’hétérogénéité du système poral du sol et de la variabilité temporelle des conditions pédoclimatiques. Ainsi, le premier défi relevé par ces travaux a été d’ordre métrologique. Cette thèse propose des avancées pratiques sur la mesure du Eh dans les sols en utilisant des électrodes combinées. Le dispositif a été appliqué au suivi d’une culture en pots (1L) de tournesols placés pendant 70 jours dans différentes conditions pédoclimatiques. Cette campagne a notamment permis d’évaluer les relations existantes entre le couple Eh /pH du sol et la forme chimique disponible des principaux nutriments présents dans celui-ci (N, P, K, Ca, Mg, S, Fe, Mn, B, Zn, Cu et Mo). Les travaux ont ainsi montré que l’azote et le fer étaient les variables clés déterminant le Eh des sols. Alors que certains éléments (N, Fe, Mn, S) sont directement dépendants des variations du Eh et du pH des sols, d’autres (Mg, Ca, P, Cu, Zn, Mo) voient leur disponibilité indirectement impactée. Considérant l’ensemble de ces résultats, la question posée a alors été de savoir si la mesure du Eh du sol permettrait, d’une quelconque manière, de fournir un indicateur capable de rendre compte de « l’état favorable » du sol dans lequel sont cultivés les plantes. Afin de répondre à ce besoin un nouveau paramètre, nommé Ehcumul a été proposé, à l’instar du degré jour qui décrit, en agronomie, les besoins en température des plantes pour leur développement. De fortes corrélations entre Ehcumul et la croissance des tournesols ont permis de confirmer qu’il existe bien des conditions optimales de Eh des sols : 440 mV/ENH, dans notre expérimentation. Plus les conditions s’éloignent de cette valeur optimale, et moins le tournesol produit de biomasse. Faisant l’hypothèse que l’activité biologique des sols pouvait jouer un rôle central sur les valeurs du Eh, le suivi du tournesol a également été mené sur des sols préalablement stérilisés par étuvage. Ayant été portés 5 jours à 105°C, ces sols ont vu leur teneur en carbone organique dissous (COD) bien supérieure aux autres, suite à une dégradation de la matière organique la plus labile. L’augmentation du COD a eu de multiples impacts, dont celui de maintenir une valeur de Eh relativement modérée. Ces résultats ouvrent des perspectives concernant l’impact des matières organiques du sol pour y maintenir des valeurs de potentiels d’oxydo-réduction optimales pour la croissance des végétauxThis work is part of a sustainable agriculture context that aims to consume fewer and fewer inputs while maintaining increasing biomass production levels, both in terms of quantity and quality. Such levels can only be achieved if cultivated plants can develop under optimal conditions, including access to the mineral elements essential for their growth. Many factors are involved in the availability of nutrients in the soil for crops such as pH or oxidation-reduction potential (Eh). Several authors have shown that plants grow within a specific Eh/pH range and are able to alter these parameters in the rhizosphere to ensure intracellular homeostasis. The final objective of this study is to understand the effects of soil redox potential on mobility and availability of nutrients to the plant. The need to carry out measurements for both Eh and pH, in situ in the soil with plants is a real matter. Measuring soil Eh is essential but complex due to the lack of measurement reliability resulting from high temporal variability and metrological challenges. This work proposes practical advancements for measuring Eh in soils using combined electrodes. The protocol was applied to monitor a sunflowers pot culture (1L) for a 70 days campaign under different soil and climate conditions. The relationships between soil Eh / pH and the availability of nutrients presents in the soil (N, P, K, Ca, Mg, S, Fe, Mn, B, Zn, Cu and Mo) has been analysed. This study has highlighted the impact of nitrogen and iron in soil Eh values. While some elements (N, Fe, Mn, S) are directly impacted by soil Eh and pH variations, others (Mg, Ca, P, Cu, Zn, Mo) have their mobility and availability indirectly affected. Considering all these results, the objective of this experiment was to determine if soil Eh would in any way provide an indicator that could represents the "favourable state" of soil for plants growth. To achieve this objective a new parameter, called Ehcumul, has been proposed, similar to the degree day, which describes, in agronomy, the temperature needs for plants growth. Strong correlations between Ehcumul and sunflower growth revealed the existence of optimal soil Eh conditions: 440 mV/ENH, in our experiment. Assuming that biological activity of the soils could play a central role in Eh values, sunflower monitoring was also carried out on soils previously sterilized by drying (105°C for 5 days). The dissolved organic carbon (DOC) contents of these soils is increased compared to non-sterilised soils, due to degradation of the most labile organic matter. The consequence was a moderated and constant Eh value. These results open up perspectives on the impact of soil organic matter to maintain optimal soil redox potential values for plant growth
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Richard, Paul François. "A computer analysis of the flow of water and nutrients in agricultural soils as affected by subsurface drainage." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29171.
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A computer model was developed in order to determine the effects of drainage practices on nutrient losses from level agricultural soils.
The model performs a daily simulation of the vertical flow of water, nitrogen, phosphorus, and heat, and of the growth of crops. A water flow submodel calculates the depth of the water table based on daily predictions of evaporation, transpiration, flow to drains and ditches, and deep percolation. An original saturated-unsaturated flow algorithm is used to determine moisture infiltration, redistribution, and upward flow in the soil matrix, as well as bypassing flow in the soil macropores and horizontal flux between the soil matrix and the macropores, and surface runoff. Nutrient movement occurs by mass flow. Heat flow, nutrient biochemical transformations, and crop growth are determined by using well established relations.
Field tests were carried out for a period of two years on an experimental site in the Lower Fraser Valley of British Columbia. The water table depth was measured on a continuous basis. Grab samples of drainwater and observation wells were obtained periodically and analyzed for nitrogen (N0₃-N, NH₄-N, and TKN) and phosphorus (P0₄-P and TP). The field results show a decrease in the concentration of all nutrients over the sampling period, and provide evidence that denitrification and bypassing flow are important mechanisms affecting the nutrient balance of this soil.
These results were used to calibrate the model. An excellent fit of the observed water table profile and an adequate fit of the observed drain concentration of nitrate were obtained. The simulation revealed that bypassing flow is a very important transfer mechanism in this soil and must be included in order to obtain a satisfactory fit of the experimental data.
A sensitivity analysis of the model showed that the patterns of moisture flow have a predominant influence on the rate of nutrient leaching. In particular, it was found that the nutrient concentration in drain water is a strong function of the hydraulic conductivity of the soil matrix and of the horizontal distance between the soil macropores, which control the ratio of moisture flow in the soil matrix to the macropore flow and the lateral diffusion of nutrients between the soil matrix and the macropores.
The effects of four different drainage designs on nutrient losses were simulated over a period of two years for three different soils and two different nutrient distributions in the soil. It was found that there is a large difference between the amount of nutrients leached from drainage systems using different drainage coefficients. There was also a large difference in the response of two drainage designs based on the same drainage coefficient but using different depth and spacing of drains. Transient effects, as determined by the initial vertical distribution of the nutrients, were seen to remain dominant over the two year duration of the simulation.
The model was found to be useful in explaining the apparent contradictions found in the literature assessing the effects of subsurface drainage on nutrient losses. The results from the model show these effects to be strongly site and condition specific. Furthermore, the model shows that soils and drainage designs that produce similar volumes of drain flow may exhibit very different leaching responses, and that drainage designs equivalent from a hydraulic standpoint can be very dissimilar in their potential for leaching nutrients. The model provides a tool which can be used to determine the appropriateness of different drainage designs in soils where minimizing nutrient losses is critical.Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
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Knecht, Billberger Magnus F. "Plant growth - stoichiometry and competition : theory development in ecosystem ecology /." Uppsala : Dept. of Ecology and Environmental Research, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200624.pdf.
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Moller, Leandra. "Soil yeasts, mycorrhizal fungi and biochar: their interactions and effect on wheat (Triticum aestivum L.) growth and nutrition." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20417.
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Thesis (MSc)--Stellenbosch University, 2012.ENGLISH ABSTRACT: In order to test the effect of different plant growth-promoting strategies on Triticum aestivum L. (wheat), we investigated the ability of biochar and a grain-associated soil yeast, to improve the growth of this crop. Our first goal was to study the effect of biochar amendments to sandy soil on the growth and nutrition of wheat in the presence of mycorrhizal fungi. This was accomplished by amending soil with 0%, 1%, 2.5%, 5% and 10% (w/w) biochar and cultivating wheat plants in these soil-biochar mixtures. After harvesting, plant growth and mycorrhizal colonization of roots were measured. In addition, we studied the nutritional physiology of these plants with regards to nitrogen (N), phosphorous (P) and potassium (K) concentrations, as well as the growth efficiencies and uptake rates of these nutrients. We found that wheat growth was improved by biochar amendments to soil, probably as a result of elevated K levels in the plant tissues supplied by the biochar amendments. The second goal of this study was to obtain a soil yeast from the rhizosphere of another monocot in the family Poaceae, i.e. Themeda triandra Forssk. (red grass), and then evaluate this isolate for its ability to improve wheat performance. Three different Cryptococcus species were isolated from the rhizosphere of wild grass, i.e. Cryptococcus zeae, Cryptococcus luteolus and Cryptococcus rajasthanensis. Since C. zeae was previously isolated from maize, an isolate representing this species was selected to be used in further experimentation. With the ultimate goal of testing the ability of this yeast to improve wheat growth, its effect on wheat germination was investigated and compared to that of two other soil yeasts, i.e. Cryptococcus podzolicus CAB 978 and Rhodotorula mucilaginosa CAB 826. These three yeasts were subsequently tested for their ability to improve wheat growth in pot cultures in a greenhouse. After one and two months of growth, the culturable yeasts present in the rhizosphere and bulk soil were enumerated. The effects of these yeasts were elucidated by measuring wheat growth in terms of dry weight, as well as root and shoot relative growth rates (RGR). Changes in wheat nutrition were evaluated by determining the concentrations, growth efficiencies and uptake rates for P, K, zinc (Zn) and iron (Fe). During this study, it was found that only C. zeae CAB 1119 and C. podzolicus CAB 978 were able to enhance seed germination. Similarly, it was shown that C. zeae CAB 1119 was able to improve wheat growth during the first and second month of cultivation, whereas C. podzolicus CAB 978 only improved growth during the first month, and R. mucilaginosa CAB 826 had no effect on growth. This improved growth could be attributed to C. zeae CAB 1119 improving the P, K, Zn and Fe growth efficiency of wheat, which positively influenced the root and shoot RGR, and subsequently wheat growth. Our final goal was to test whether C. zeae CAB 1119 could affect wheat growth and nutrition when cultivated in sandy soil, which contained natural microbial consortia and 10% (w/w) biochar. Plants treated with viable or autoclaved cells of C. zeae CAB 1119, were subsequently cultivated in soil only or soil amended with biochar. After one month, plants were harvested and growth was measured with regards to dry weight, root RGR and shoot RGR. In addition, the concentrations of P, K, Zn and Fe were analyzed for these plants, where after the growth efficiencies and uptake rates were calculated for these four nutrients. Results indicated that plants growing in soil amended with biochar, and treated with viable C. zeae CAB 1119, showed the best growth. The increased root and shoot RGR witnessed in these plants was probably due to increased concentrations of P and K in the plants. This study opens new avenues of research with regards to the bio-fertilizers of wheat.
AFRIKAANSE OPSOMMING: Die uiteindelike doel van die studie was om die effek van verskillende plantgroei bevorderende metodes op die groei van Triticum aestivum L. (koring) te ondersoek. Dus het ons die vermoë van houtskool en ‘n graan-geassosieerde grondgis getoets om die groei van dié plant te bevorder. Die eerste doel van die studie was om die effek van houtskool toedienings tot sanderige grond te evalueer. Dit is bewerkstellig deur 0%, 1%, 2.5%, 5% en 10% (w/w) van die houtskool by die sand toe te voeg en koring in die houtskool-sand mengsels te kweek. Na die verlangde groei tydperk is die koring geoes en die mikorrizale kolonisasie op en in die koring wortels bepaal. Gedurende hierdie studie is die effek van bogenoemde toedienings op die fisiologie van die plante ondersoek deur die konsentrasies, opname tempo’s, en groei ekonomie van die plante vir stikstof (N), fosfaat (P) en kalium (K) te bepaal. Ons het gevind dat die groei van koring deur die toediening van houtskool bevorder is en dit blyk dat dié effek weens die teenwoordigheid van hoë K vlakke in die plantweefsel is. Die tweede doel van ons studie was om ‘n gis vanuit die risosfeer van ‘n monokotiel wat aan die familie Poacea behoort, naamlik Themeda triandra Forssk. (rooigras) te isoleer. Die vermoë van die isolaat om die groei van koring te bevorder was daarna getoets. Drie verskillende Cryptococcus spesies was vanuit die risosfeer van rooigras geïsoleer, nl. Cryptococcus zeae, Cryptococcus luteolus en Cryptococcus rajasthanensis. Omdat C. zeae in ‘n vorige studie vanaf mielies geisoleer was, is ‘n isolaat van hierdie spesie gebruik in verdere eksperimente. Met die doel om te bepaal of dié gisspesie koringgroei kan bevorder, was die effek van C. zeae op die ontkieming van koring bestudeer en vergelyk met dié van twee ander grond giste, nl. Cryptococcus podzolicus CAB 978 en Rhodotorula mucilaginosa CAB 826. Hierdie drie giste is ook ondersoek om die groei van koring in ‘n glashuis te bevorder. Na een en twee maande se groei was die getalle van giste teenwoordig in die risosfeer en grond verder weg van die wortels bepaal. Die effek van dié giste op die groei van koring is bepaal in terme van droë gewig asook die relatiewe wortel en halm groei tempos. Veranderinge in die nutrient status van koring is ondersoek deur die konsentrasies, groei-ekonomie en tempo van opname vir P, K, sink (Zn) en yster (Fe) te bepaal. Ons het gedurende dié studie gevind dat C. zeae CAB 1119 en C. podzolicus CAB 978 die ontkieming van koring kon verbeter. Ons het ook gevind dat C. zeae CAB 1119 die groei van koring gedurende die eerste en tweede maand van groei kon bevorder, terwyl C. podzolicus CAB 978 dit net gedurende die eerste maand kon vermag en R. mucilaginosa CAB 826 geen effek gehad het nie. Die verbeterde groei kon aan C. zeae CAB 1119, wat die P, K, Zn en Fe groei effektiwiteit van die plante verbeter het, toegeskryf word. Die verbetering van groei effektiwiteit het ‘n positiewe invloed op die relatiewe groeisnelheid van die wortels en halms gehad, en dus op koringgroei. Die laaste doel van die studie was om te bepaal of C. zeae CAB 1119 die groei van koring kon bevorder wanneer die koring in sand wat natuurlike mikrobiese populasies bevat en met houtskool aangevul is, gekweek word. Plante is met lewensvatbare of nielewensvatbare selle van C. zeae CAB 1119 behandel en gekweek in sanderige grond, en/of grond waarby 10% (w/w) houtskool toegevoeg is. Die plante is na een maand geoes en die groei bepaal in terme van droë massa en die relatiewe wortel en halm groei tempos. Die konsentrasies van P, K, Zn en Fe in die plante, asook die fisiologie van die plante, nl. groei ekonomie en tempo van opname, met betrekking tot P, K, Zn en Fe is bepaal, Ons het gevind dat plante wat in die houtskool-grond mengsel gekweek is en met lewensvatbare selle van C. zeae CAB 1119 behandel is die beste groei getoon het. Die verbeterde relatiewe groei tempos van die wortels en halms was mees waarskynlik die gevolg van verhoogde P en K konsentrasies in die plante. Hierdie studie toon nuwe resultate in verband met die gebruik van biologiese alternatiewes tot kunsmis.
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Kranabetter, John Marty. "Interacting effects of soil nitrogen supply and light availability on understory sapling growth and foliar attributes." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1290.
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Light availability in forest understories is a well recognized constraint on sapling growth, but limitations in soil nitrogen (N) availability, and the link to foliar photosynthetic capacity, typically receive less consideration in describing stand dynamics. My primary hypothesis is that light and soil N availability have species-specific effects on photosynthetic activity and growth, and that together these resources will better define understory development in complex forests. To test these relationships, I examined 1) soil N indices and the tradeoffs between soil fertility and light attenuation in old-growth forest understories; 2) the effects of light and N constraints on understory sapling foliar N concentration (N%), N per unit area (Na), and natural abundance of ¹³C; 3) the effects of light and soil N supply on species growth and photosynthetic activity in a factorial field experiment; and 4) the mechanisms responsible for the stagnation of understory saplings. Soil N indices incorporating dissolved inorganic N and organic N were useful in characterizing differences in N supply among contrasting sites. Understory light availability declined with increasing soil N supply, while understory Abies lasiocarpa had strong correlations between foliar N% and soil N availability, despite shading effects. In partial-cut forests, understory Tsuga heterophylla and Picea glauca x sitchensis had consistent foliar N% across gradients of light availability; in contrast, foliar N% of Betula papyrifera and Thuja plicata declined with increasing shade, which would distort assessments of soil fertility and perhaps contribute to increased mortality of these species in deep shade. Strong correlations between foliar Na and ¹³C or growth increment suggest foliar N per unit area is the simplest integration of light availability and N nutrition on leaf photosynthetic activity. Ontogenic interactions that occur among foliar attributes and tree size in forest understories, especially for saplings < 1 m in height, contribute to time effects on growth patterns and emphasize the need for long-term studies of species autecology and stand dynamics. My experimental manipulation of light and N supply on saplings was ineffective, and future research using natural gradients in site productivity may be more fruitful in defining species response to light and N interactions.
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Murata, Monica Rujeko. "The impact of soil acidity amelioration on groundnut production and sandy soils of Zimbabwe." Diss., University of Pretoria, 1995. http://upetd.up.ac.za/thesis/available/etd-08152003-155125.
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Harper, George James. "The effect of cold storage duration and soil temperature on the photosynthetic ability of Picea glauca seedlings." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28774.
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In response to concern over the failure and poor growth of many interior and white spruce plantations in British Columbia the effect of storage duration and soil temperature on the photosynthetic ability of white spruce seedlings was explored. Seedlings of Picea glauca were dark freezer stored (-5°C) from 9.6 to 30.6 weeks, thawed and grown for 28 days in a growth chamber at three different soil temperatures (3,7,11°C). During this period gas exchange variables and chlorophyll fluorescence kinetics were followed.
Seedlings stored for periods of 22 weeks or longer had significantly lower rates of photosynthesis dependent on the outplanting soil temperature. Stomatal conductance was initially low upon outplanting and showed a recovery period of 4-7 days duration. The level of stomatal conductance increased in seedlings after they were stored for 26.1 weeks or longer. Chlorophyll fluorescence measurements of seedlings stored from 22 to 30.6 weeks showed a recovery period in photosynthetic efficiency (Fy/Fp) related to changes in photosynthesis. A decrease in seedling Fy/Fp with increasing periods of storage was noted at day 5 after outplanting. A disproportionate increase in new root growth with the increasing soil temperatures, measured after the 28 day growth period, suggested a soil temperature threshold for root growth exists between the 7°C and ll°C. In contrast, the stomatal conductance and photosynthesis results suggest the seedling shoots were not directly affected by the cold soil temperatures. In general, the results suggest Picea glauca seedlings stored longer than 22 weeks in freezer conditions have reduced photosynthetic ability, root growth and overall vigor. Fluorescence and bud break data suggest the reduction was possibly due to freezing damage sustained in storage affecting photosynthetic electron transport through photoinhibition upon returning seedlings to the light.Forestry, Faculty of
Graduate
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Randhawa, Nirmal Singh. "Impact of fertilization and vegetation management on growth and nutrition of white spruce seedlings and related soil nitrogen transformations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0003/MQ29460.pdf.
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Scurich, Justin J. "STRAWBERRY GROWTH, YIELD, FRUIT NUTRITION, AND CONTROL OF VERTICILLIUM WILT WITH PRE-PLANT SOIL FUMIGANTS, OZONE, AND BIOLOGICAL CONTROL." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/714.
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Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, chloropicrin, and 1, 3-Dichloropropene. Additional treatments included ozone gas (six treatments) and biological control (three treatments). Collected data included total plant yield, individual berry weight, number of fruit produced per plant, plant vegetative weight, infection status, and mineral concentration of fruit (calcium, magnesium, potassium, iron, zinc, manganese, carbon, and nitrogen). Plants grown in ‘clean’ soil were less likely than plants grown in ‘infested’ soil to be infected with Verticillium. Plants grown in soil treated with MB had higher plant weight and yield than did non-treated control. Ozone and biological control treatments did not have statistically higher yield than non-treated control plants nor statistically lower yield than plants grown in soil treated with MB. Individual berry weights had a narrow range while the number of berries produced per treatment had a wide range. Data suggests strawberry yield is dependent on the number of berries produced per plant. Plants with high vegetative weight produced the highest yield suggesting large plants produce many berries resulting in higher yield.
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Yeap, Simon G. H. "Investigating the impacts of groundwater on soil properties and pasture nutrition in irrigated agriculture, Pilbara region of Western Australia." Thesis, Yeap, Simon G.H. (2014) Investigating the impacts of groundwater on soil properties and pasture nutrition in irrigated agriculture, Pilbara region of Western Australia. Honours thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/32100/.
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Dewatering of groundwater systems has become a common practice for iron ore mining in the Pilbara region of Western Australia. While the discharge of surplus water to local tributaries and re-injection into the aquifer are widely practiced, the re-use of this water for irrigated forages is an innovative solution. However, the chemistry of the groundwater and the impacts on soil properties from long-term application of groundwater need to be assessed.
Surplus water from the Marandoo iron ore mine is utilised to irrigate Rhodes grass (Chloris gayana) for hay production at the Hamersley Agricultural Project (HAP). After amendment with nutrients, the irrigation water was slightly alkaline (pH 8.0) and slightly brackish-sodic (total dissolved solids, TDS, of 580 mg/L) with Ca (61 mg/L), Mg (50 mg/L) and Na (43 mg/L) as the dominant cations and bicarbonate (270 mg/L) as the dominant anion. This study aims to identify the implications of irrigation with this water for pasture production and soil management.
Following the commencement of irrigation in October 2012, significant changes and trends in soil properties and leaf nutrient composition of C. gayana were examined over a 15 month period, based on a quarterly sampling program across 10 centre-pivot irrigation systems. Analysis initially showed that the continuation of current trends could result in: (1) increases in soil sodicity, since ESP levels had exceeded 5% at 0-10 cm and 7% at 20-30 cm, and (2) alkalinisation, such that the soil pH is predicted to reach ~8.2. However, subsequent analysis with pre-washed soil samples to remove soluble salts indicated that irrigation had not caused a measureable change in the ESP and hence no change in the sodicity of HAP soils.
Nonetheless, the geochemical model WEB-PHREEQ suggests the precipitation of carbonate, (hydr)oxide and phosphate (apatite) minerals of Ca, Mg, Fe and Mn could also impose a risk for immobilising nutrients applied from irrigation water, given suitable conditions for nucleation and crystal growth. Moreover, changes in the relative abundance of soil exchangeable cations may also adversely affect plant nutritional balance whereby exchangeable Mg2+ as a percentage of cation exchange capacity has significantly increased while the percentages of exchangeable Ca2+ and K+ have significantly decreased.
In the next 20 years, based on the estimated duration of the HAP, soil alkalinisation could emerge as a problem by suppressing the availability of various nutrients. Future monitoring and research, in conjunction with effective irrigation and soil management practice, will hence be imperative to ensure long-term sustainability of pasture production at the HAP, as well as for rehabilitation of soils after decommissioning.
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Sherfy, Mark Huffman. "Nutritional Value and Management of Waterfowl and Shorebird Foods in Atlantic Coastal Moist-Soil Impoundments." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/26575.
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The mid-Atlantic coast region, an area of continental significance to migratory and wintering waterfowl and shorebirds, contains numerous moist-soil impoundments that are managed for waterbirds. Positive relationships between nonbreeding body condition and subsequent survival and reproduction have been documented for waterfowl, yet few evaluations of habitat management consider nutritional value of foods. I assessed 2 types of impoundment manipulation, using nutritional data as a basis for evaluation.Invertebrate and plant seed production were measured in disced and control plots in impoundments at Back Bay National Wildlife Refuge. Seed production was higher (P = 0.0614) in disced (1052 ± 468 kg / ha) than in control (529 ± 226 kg / ha) plots. Discing produced higher Chironomid larva abundance during spring, and higher abundance of Amphipods and non-Chironomid Diptera during fall. Waterbird predation reduced abundance of Chironomid larvae, non-Chironomid Diptera, and Amphipods. The predation effect on Total Invertebrate dry mass was 2x higher in disced than in control areas.Invertebrate production also was measured in habitats denuded by foraging greater snow geese (Anser caerulescens atlantica) at Prime Hook National Wildlife Refuge. Chironomid larvae were 2 -6x more abundant in vegetated habitats than in areas where geese had foraged intensively, but exclosure data showed little effect of shorebird predation on invertebrate abundance. These results suggest that high goose populations can reduce waterbird food availability, and that shorebird use of invertebrates in denuded habitats is low.Mean true metabolizable energy (TME) of moist-soil seeds and invertebrates in blue-winged teal (Anas discors) ranged from -0.18 - 3.47 kcal / g. Correction of means for fiber concentration eliminated negative values, thereby enhancing their practical value.Potential duck use-days predicted using TME and seed production data were about 2x higher for disced than for control areas at Back Bay. Magnitude of the discing effect on duck use-days was largely insensitive to different estimates of seed nutritional value, although substantial variation in absolute measures of potential carrying capacity occurred. Discing positively influenced invertebrate abundance, and quantity and quality of moist-soil seeds produced, and should be considered a viable habitat management approach for both shorebirds and waterfowl.Ph. D.
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Zou, Congming. "SOIL MANAGEMENT AND NITROGEN DYNAMICS IN BURLEY TOBACCO ROTATIONS." UKnowledge, 2015. http://uknowledge.uky.edu/pss_etds/64.
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Agronomic practices, including tillage, crop rotation and N fertilization, have been developed to efficiently manage soil N dynamics and crop N nutrition. These practices can affect soil organic carbon (SOC) and soil total nitrogen (STN) sequestration, and consequently influence soil nitrogen mineralization (SNM) and crop N nutrition. However, little research has been systematically and simultaneously conducted to examine the effect of agronomic management on (1) SOC and STN stocks; (2) SNM; and (3) crop N nutrition. Burley tobacco (Nicotiana tobacum L.) is a N demanding crop and subject to inefficiency in N fertilization. Moreover, conservation tillage and rotation have been integrated into traditionally tillage intensive tobacco cropping systems. Thus, a tobacco tillage and rotation study was used to test how agronomic practices can affect N dynamics and crop N status in a series of sequential experiments.
Firstly, different tobacco production systems were utilized to investigate the effects of tillage and rotation on soil aggregate stabilization and associated SOM sequestration. No-tillage and rotation management enhanced SOC and STN stocks, mainly by increasing the proportion of macroaggregates and SOC and STN concentrations.
Secondly, a series of studies were conducted on SNM, including: (1) comparison of laboratory and in situ resin-core methods in estimating SNM; (2) evaluation of the influence of N fertilizer application on SNM; and (3) comparison of chemical indices for predicting SNM across management treatments over time. Laboratory method had different results relative to in situ method due to sample pretreatments. Fertilizer N application had a priming effect on SNM, but priming depended on both the N fertilizer rate and the background SOM level. The effect of rotation/tillage treatments on SNM was stable across years and SOC appeared to be the best indicator of SNM among other soil carbon and N estimates.
Thirdly, a N fertilizer study for different tillage systems was conducted in 2012 and 2013. Crop parameters and plant available N (PAN) were collected to investigate the impact of tillage on tobacco production. Crop parameters showed that no-tillage can result in N deficiency in dry years. Similar PAN for both tillage methods suggested N deficiency in no-till tobacco was due to the crop’s lower N uptake capacity. In 2014, tobacco root analysis confirmed that no-tillage can result in less root exploration of the soil volume than conventional tillage.
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Blotevogel, Simon. "Etude des transferts élémentaires et mécanismes biogéochimiques dans le continuum sol-plante-vin par l'utilisation de traceurs isotopiques et biochimiques." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30373/document.
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Dans l'ouest de l'Europe, une grande importance est accordée à la composante sol dans l'élaboration des vins. La nutrition minérale est la principale voie par laquelle le sol peut avoir une influence sur la vigne et par conséquent sur le vin qui en est issu. Dès lors, ce travail de thèse appréhende la question plus large des transferts élémentaires entre le sol et la plante à travers de l'utilisation d'outils géochimiques en milieu viticole. Une combinaison de techniques impliquant des indicateurs classiques tels que les rapports élémentaires ou des bilans de masses ainsi que des traceurs plus innovants comme les rapports isotopiques du Cu et la résonance paramagnétique électronique (RPE) est utilisée. Dans un premier temps, l'influence du sol sur la composition élémentaire du vin a été étudiée dans plus que 200 vins provenant d'Allemagne, d'Espagne, de France, et d'Italie. A cette échelle, le type de sol (classé comme calcaire ou non-calcaire) et les conditions météorologiques apparaissent comme des critères discriminants. Par la suite, deux parcelles viticoles de Soave (Italie) aux sols contrastés ont été étudiées afin de d´déterminer l'influence du type du sol sur les vignes. Même si les sols présentent des propriétés pédologiques différentes, une pédogénèse complexe a induit des propriétés géochimiques similaires. Dans les vignes, les traceurs élémentaires et biochimiques montrent que la variabilité inter-annuelle et inter-individuelle est plus grande que la différence liée au sol lui-même. Néanmoins, il est possible de déterminer quel est le sol considéré par l'étude des rapports isotopiques du Sr. Parmi tous les nutriments et éléments toxiques généralement étudiés pour leur mobilité dans les sols, le cuivre a été suivi dans la dernière partie de cette thèse, essentiellement du fait de son épandage toujours massif comme fongicide en viticulture. En effet, les pesticides cupriques comme la bouillie bordelaise sont utilisés depuis environ 150 ans en viticulture. Le Cu s'accumule d`es lors dans les sols et les conséquences ´ecotoxicologiques en font un sujet de plus en plus sensible. Parmi les pesticides analysés dans notre étude, les rapports isotopiques du Cu varient autant entre les différents fongicides que dans les sols étudiés dans la littérature, rendant ainsi impossible l'utilisation de ces isotopes comme traceurs d'origine du Cu dans les sols. [...]In western Europe, soil is of primordial importance for wine making. Soil qualities are often discussed and an influence on wine flavor is frequently inferred. However, evidence for a role of soil chemistry on wine composition and taste is scarce, but mineral nutrition of grapevine plants is one possible way of influence. This thesis approaches the complex question of elemental cycling between soil and plant through the use of geochemical tracers in vineyard environments. A combination of traditional tracers such as elemental ratios and mass balances as well as innovative tools such as Cu isotope analysis and electron paramagnetic resonance (EPR) are used on different observation scales. The influence of soil type on wine elemental composition was investigated using over 200 wine samples from France, Germany, Italy and Spain. Results of chemical analysis were then statistically linked to environmental conditions. At this scale, elemental contents of wine vary depending on soil type (calcareous or not), meteorological conditions, and wine making practice. To determine which soil properties can influence the chemical composition of grapevine plants, two vineyard plots on contrasted soils in Soave (Italy) were examined. Soil forming mechanisms were studied along two catenas and subsequently linked to elemental composition of grapevine plants and biochemical markers of plant health. Even though soil morphology was different, complex soil forming processes led to similar geochemical properties of soils. Differences in plant chemical compositions between soil types are small compared to inter-individual and inter-annual variability. However the use of Sr isotopic ratios allows the determination of the pedological origin of plants. In a next step, the fate of Cu pesticides in vineyard soils was studied. Cu-based pesticides have been used for almost 150 years in European vineyards and Cu accumulates in soils, so that the fate of Cu and its ecotoxicological implications are of growing importance. Therefore, Cu mobility in vineyard soils and transfer to grapevine plants were investigated using stable Cu-isotope ratios and EPR-measurements. Isotope ratios of Cu-based fungicides vary largely between products, covering Cu isotope ratios in soils reported in literature and thus making source tracing impossible. However, Cu isotope ratios are useful for tracing biogeochemical mechanisms of Cu transport in soils. The vertical transport of Cu in different soil types was investigated in the Soave vineyard using a combination of mass balance calculations, kinetic extractions and δ65Cu-isotope ratios. Results suggest that Cu can be transported to depth even in carbonated environments. Besides it is shown that heavy organic-bound Cu is lost from carbonated soil columns likely caused by dissolution of Cu carbonates by organic matter. [...]
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Venter, Annari. "Comparing plant yield and composition with soil properties using classical and geostatistical techniques." Diss., University of Pretoria, 2003. http://hdl.handle.net/2263/23916.
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Plant nutrient management plays a vital role in the success or failure of modern Lucerne production. In South Africa, Lucerne is produced under a wide range of climatic conditions, under dryland and irrigation and in some areas throughout the year. This means that there is a continuous demand for nutrients under a wide range of environmental conditions. The most important factors affecting the nutrient requirement of Lucerne is yield, the cutting schedule, climate and management practices. To enable site-specific crop requirements, the spatial variation of soil and plant properties within a field can be managed with the use of geostatistical techniques. Some work has also been done to evaluate the use of geostatistics in the design of agricultural field experiments to provide better field characterization and improve plot layout. The aim of this study was to compare plant yield and composition with soil properties using both classical and geostatistical techniques. The study was conducted from June 2001 to February 2002 on an 18ha Lucerne stand in the Brits district in the North West Province. A rectangular area of 160m X140m was demarcated as the study area and comprised of two soil units (Hutton and Shortlands forms). Seventy-two sampling points (nodes) were laid out on a 20m square grid, with an additional 90 sampling points laid out on a 2.5m square grid at six randomly selected node points. Soil (0-300 mm) and plant samples were taken within a 0.6m square at each of the sampling points for chemical analysis. Starting in June 2001, yield sampling was done on six occasions, at approximate intervals of 5 weeks. A randomized complete block design trail layout was superimposed on the geostatistical grid design and consisted of seven pseudo treatments, replicated four times. Basic statistical analysis were performed and spatial presentations of the variation of the plant and soil properties and Lucerne yield were made using geostatistical analyses. Analyses of variance were used to test for differences between pseudo treatments for all plant and soil properties. The two soils on the stud site, exhibited differences in certain properties, which caused a bi-modal population in the data. Poor correlations were found between plant nutrient uptake and soil properties as well as yield, with little or no resemblance when comparing their spatial distribution. This emphasizes the fact that the uptake of elements is not solely dependant on the concentrations thereof in the soil solution, but on other factors. Temporal variations in Lucerne yield were also observed. Although there were large differences in spatial variation of Lucerne yields across harvesting events, similar spatial patterns were evident. From an analysis of variance of the RCB design it was concluded that the experimental field was homogeneous enough to lay out a standard block design experiment. However, scrutiny of the structure of spatial variability of pH(H2O) revealed that the standard RCB designs did not provide homogeneous blocks with respect to soil variability. The consequent redesign of the experiment whereby all plots were randomly allocated to treatments and replications, led to dramatically different results: significant differences were obtained for plant and soil properties as a function of the pseudo treatments. From this study it is clear that spatial variability of soil and plant properties can jeopardize the results of a standard block design field experiment and it is therefore recommended that the layout of field experiments should be designed to the cognizance of the spatial variation of a soil property that correlated highly with a chosen response variate.Dissertation (MSc (Soil Science))--University of Pretoria, 2007.
Plant Production and Soil Science
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Dube, Ernest. "Soil fertility enhancement through appropriate fertilizer management on winter cover crops in a conservation agriculture system." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/d1001044.
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A study was carried out to determine the effects of oat (Avena sativa) and grazing vetch (Vicia darsycapa) winter cover crops and fertilizer application on SOM, phosphorus (P) pools, nutrient availability, nutrient uptake, maize yield and seedbanks of problematic weeds in an irrigated maize-based conservation agriculture (CA) system. A separate experiment was carried out to investigate the effects of the winter cover crops on nitrogen (N) management, N use efficiency and profitability. After four years of continuous rotation, the winter cover crops significantly (p<0.05) increased particulate SOM and hot water soluble carbon in the 0 – 5 and 5 – 20 cm soil depths. When fertilized, oat was better able to support SOM sequestration in water stable aggregates at 0 – 20 cm whilst grazing vetch was more effective at 20 – 50 cm. Where no fertilizer was invested, there were significant (p<0.01) reductions in biomass input and SOM on oat-maize and weedy fallow-maize rotations whereas vetch-maize rotations did not respond, both at 0 – 5 and 5 – 20 cm. Targeting fertilizer to the winter cover crop required less fertilizer, and yet gave a similar SOM response as targeting the fertilizer to the maize crop. In addition to increasing SOM in the surface soil (0 – 5 cm), the winter cover crops significantly (p<0.05) increased labile pools of P, including microbial P. The cover crops also significantly (p<0.05) increased maize P concentration during early growth, extractable soil P, Cu, Mn, and Zn but had no effect on Ca and K. Grazing vetch increased soil mineral N but reduced extractable soil Mg. Without fertilizer, there were sharp declines in maize grain yield on oat and weedy fallow rotations over the four year period, but less so, on the grazing vetch. Grazing vetch increased maize growth, grain yield response to N fertilizer, nitrogen use efficiency (NUE) and profitability for fertilizer rates below 180 kg N ha-1. Oat effects however on maize yield and NUE were generally similar to weedy fallow. Based on the partial factor productivity of N, the highest efficiencies in utilization of fertilizer N for maize yield improvement under grazing vetch and oat are obtained at 60 kg N ha-1 and would decline thereafter with any increases in fertilizer application rate. Grazing vetch gave N fertilizer replacement values of up to 120 kg N ha-1 as well as the highest marginal rates of return to increasing N fertilizer rate. The cover crops were more effective than the weedy fallow in reducing seedbank density of Digitaria sanguinalis, Eleusine indica, Amaranthus retroflexus and Datura stramonium at 0 – 5 cm soil depth, causing weed seed reductions of 30 - 70%. The winter cover crops however, selectively allowed emergence of the narrow leafed weeds; Cyperus esculentus and Digitaria sanguinalis in the maize crop. The findings of this study suggested that grazing vetch is suited for SOM improvement in low fertilizer input systems and that fertilizer is better invested on winter cover crops as opposed to maize crops. Oat, on the other hand, when fertilized, would be ideal for C sequestration in water stable aggregates of the surface soil. Grazing vetch is ideal for resource poor farmers who cannot afford mineral fertilizers as it gives grain yield improvement and high fertilizer replacement value. Grazing vetch can produce enough maize yield response to pay its way in the maize-based systems and oat may not require additional N than that applied to the weedy fallow. Phosphorus and Zn are some of the major limiting essential plant nutrients on South African soils and the winter cover crops could make a contribution. The cover crops also hasten depletion of some problematic weeds from seedbanks, leading to reduced weed pressure during maize growth.
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Jasson, Timothy Ivan. "Effects of compost tea extract on growth, nutritional value, soil quality of Hypoxis hemerocallidea and Siphonochilus aethiopicus." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2791.
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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2017.The exact responses to the concentration of compost tea extract and methods of irrigation application were not previously measured on Hypoxis hemerocallidea and Siphonochilus aethiopicus. Commercial exploitation, habitat loss and degradation, overharvesting, and enhancement of their medicinal properties, have led to this investigation and the need to replenish both these valuable plant species. This is crucial for plant survival, especially in the wild and for use of the traditional medicinal plants. Hypoxis hemerocallidea and Siphonochilus aethiopicus, known as star flower and wild ginger respectively continue to decline, due to overharvesting from their natural habitat. Both these species have tremendous traditional medicinal value among localized African people. To enhance their commercial cultivation, compost tea extracts, in the following ratios (no catalyst added (control1); T 1000:1, T750:1, T500:1, and T250:1L) were applied in equal dosages to determine an optimal compost tea extract ratio. The experiment was conducted in a temperature controlled greenhouse. Mushroom compost (500 g, per brew) was used for all extracts. Brewing was done with no catalyst added (Control 1), and 24 hours later another brew was done with catalyst added, weekly for 20 weeks. The Control treatment received water only. Both species were slow growing and comparatively, the Hypoxis plants responded faster than the Siphonochilus plants. In this investigation, plant growth parameters such as plant height, number of leaves, leaf width, leaf length and leaf colour, were measured and evaluated. Despite the plants positive response to the mushroom compost tea extracts, across all the above plant growth parameters, no significant differences were noted between the treatments during the twenty-week application period. Leaf chlorophyll content peaked in week 11 of the hypoxis plants and was the highest in week 14 of the Siphonochilus plants with no significant interaction between weeks vs. treatment over the twenty-week experiment. The chlorophyll readings indicate that both species increased their chlorophyll production over time. Although the total wet leaf length, root length, corm diameter, leaf weight, corm weight and root weight of Hypoxis were non-significant between treatments, T500:1 total wet weight was significantly higher when compared to the rest of the treatments. The total dry weight analysis of hypoxis was non-significant. Control Calcium level was significantly lower between the control and the treatments of the Hypoxis total dry leaf nutrient analysis. The Hypoxis dried roots nutrient analysis was non-significant across treatments.
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Soratto, Rogério Peres [UNESP]. "Aplicação de calcário e gesso em superfície na implantação do sistema de plantio direto." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/100003.
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soratto_rp_dr_botfca.pdf: 792481 bytes, checksum: 32d9518363b0fae5fab589ed74ffbe8c (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Existe interesse na busca de alternativas para a implantação do sistema de plantio direto em áreas anteriormente cultivadas no sistema convencional de preparo do solo ou sob pastagens, sem a incorporação prévia do calcário, realizando-se a calagem superficialmente desde o estabelecimento do sistema, desde que não haja impedimento físico ao crescimento radicular. Nesse sentido, o gesso agrícola, por ser mais solúvel e apresentar relativa mobilidade no solo, é apontado como alternativa para correção das camadas subsuperficiais do solo em curto prazo, podendo ser utilizado como um produto complementar ao calcário. Dessa forma, o trabalho objetivou avaliar a influência da aplicação superficial de calcário e gesso, na implantação do sistema de plantio direto, sobre as características químicas do solo, o teor de cátions solúveis na parte aérea das culturas, o crescimento radicular, a nutrição e produtividade de culturas anuais, em região de inverno seco. O experimento foi conduzido nos anos agrícolas de 2002/2003 e 2003/2004, na Fazenda Experimental Lageado, localizada no município de Botucatu (SP), em um Latossolo Vermelho distroférrico, anteriormente conduzido no sistema convencional de preparo do solo. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e quatro repetições. As parcelas foram constituídas por quatro doses de calcário dolomítico (0, 1.100, 2.700 e 4.300 kg ha-1), com PRNT = 71,2%, visando elevar a saturação por bases para 50%, 70% e 90%, respectivamente. As subparcelas foram constituídas pela ausência e aplicação de 2.100 kg ha-1 de gesso agrícola (6 x teor de argila em g kg-1, na camada de 0,20-0,40 m de profundidade). Para as culturas de verão foi utilizado o esquema de parcelas subsubdivididas, sendo as subsubparcelas constituídas por dois cultivares de arroz de terras altas...
There is great interest to search alternatives to establish the no-tillage system in fields previously cultivated on conventional tillage or on pasture, with no lime previous incorporation, using superficial liming since the beginning of system, if don't have physical impediment to root growth. Thus, the phosphogypsum, that is more soluble and with high mobility, has been an alternative to correct the subsuperficial soil layer, in a short time, and can be used as a lime complementary product. Therefore, the objective of this work was to evaluate the effects of lime and phosphogypsum surface application during the establishment of no-tillage system, on the soil chemical characteristics, on the content of water-soluble cations, in the crop shoot, on the root growth, on the nutrition and yield of annual crops, in a dry winter region. The experiment was carried out during the agricultural years of 2002/03 and 2003/2004, in an experimental area located in Botucatu County, São Paulo State, Brazil (48º 23' W and 22º 1' S) on a Haplorthox, before used with conventional tillage system. A randomized complete block design, in split-plot scheme, and four replications was used. The plots were composed by four dolomite limestone levels (0; 1,100; 2,700; and 4,300 kg ha-1), with Neutralization Power = 84.3% and Reactivity = 84.5%, aiming raise the base saturation to 50%, 70%, and 90%, respectively. The subplots were composed by without and with phosphogypsum application (2,100 kg ha-1 = 6 x clay content (g kg-1) in 0.20-0.40 m depth layer). For the summer crops a split-split-plot scheme were used. The subsubplots were constituted by two upland rice cultivars ('Caiapó' and 'IAC 202'), on agricultural year of 2002/03, and two common bean cultivars ('Carioca' and 'Pérola'), on agricultural year of 2003/2004. In the winter season of 2003 and 2004, the black oat was grown in the area... (Complete abstract click electronic access below)
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Matoka, Charles Mboya. "Bacterial community responses to soil-injected liquid ammonium nutrition and effect of temperature on Barley (Hordeum vulgare L.) grain yield formation." Göttingen Cuvillier, 2007. http://d-nb.info/987473530/04.
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Matoka, Charles Mboya. "Bacterial community responses to soil-injected liquid ammonium nutrition and effect of temperature on Barley (Hordeum vulgare L.) grain yield formation /." Göttingen : Cuvillier, 2008. http://d-nb.info/987473530/04.
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Wei, Xi. "Effects of residual veterinary antibiotics on soil enzyme activity and plant growth." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/830.
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Noronha, Sannervik Angela. "Modelling productivity of willow stands in Sweden : evaluation of concepts for radiation use efficiency and soil water and nitrogen availability /." Uppsala : Dept. of Short Rotation Forestry, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s286-ab.html.
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Carmeis, Filho Antonio Carlos de Almeida 1984. "Soil acidity management on an oxisol quality and wheat-common bean growth under a long term no-tillage system /." Botucatu, 2016. http://hdl.handle.net/11449/148617.
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Orientador: Carlos Alexandre Costa CrusciolBanca: Dirceu Maximino Fernandes
Banca: Jose Eduardo Corá
Banca: Eduardo Favero Caires
Banca: Adriano Stephan Nascente
Resumo: Os distúrbios químicos e físicos do solo estão entre os principais fatores que restringem o potencial produtivo da agricultura tropical. A baixa capacidade produtiva tem sido associada principalmente à acidez do solo e deficiência de macronutrientes, portanto, é fundamental o desenvolvimento de estratégias que ampliem a capacidade de produção de solos ácidos tropicais. O calcário e o gesso agrícola (PG) são materiais comumente empregados na agricultura para melhorar as propriedades químicas do solo, mas existem poucas informações sobre os efeitos da aplicação superficial desses produtos nas propriedades físicas dos Latossolos e nas diversas frações da matéria orgânica do solo (SOM). Diante destes aspectos, este trabalho objetivou avaliar o efeito da aplicação superficial de calcário e PG sobre os atributos químicos e físicos do solo, crescimento radicular, nutrição de plantas, componentes de produção, características tecnológicas e produtividade de trigo e feijão e sobre as diversas frações de SOM, as quais são consideradas críticas para tornar os sistemas agrícolas tropicais sustentáveis e produtivos. O delineamento experimental foi em blocos casualizados com quatro repetições. Foram estabelecidos quatro tratamentos: controle (sem aplicação de calcário e gesso); PG (2,1 Mg ha-1); calcário (2,0 Mg ha-1); e uma combinação de calcário e PG (2,0 e 2,1 Mg ha-1, respectivamente). Desde a instalação do experimento em 2002, as doses de calcário e PG foram aplicadas três vezes (2002,...
Abstract: Soil chemical and physical disorders are among major limiting factors to improve productive potential of tropical agriculture. The low productive capacity has been associated especially to soil acidity and macronutrient deficient, thus the development of strategies that improve production capacity of tropical acid soils are required. Lime and phosphogypsum (PG) are materials commonly used to improve soil chemical condition, but there is few information about the long-term effects of these products, applied superficially, especially on Oxisol physical properties and organic matter pools. Therefore, this research aimed to evaluate the effect of surface application of lime and PG on the soil chemical and physical attributes, root growth, plant nutrition, yield components, technological characteristics and yield of wheat and common bean, and soil organic matter (SOM) pools considered critical to make agricultural tropical systems sustainable and productive. A randomized complete block design was used and treatments were replicated four times. Four treatments were carried out: control (without lime and gypsum application); PG (2.1 Mg ha-1); lime (2.0 Mg ha-1); and a combination of lime and PG (2.0 and 2.1 Mg ha-1, respectively). Since the experiment was established in 2002, the amendments rates have been applied three times (2002, 2004, and 2010). Superficial liming alleviated Oxisol acidity in the surface and subsurface layers after twelve years under soil acidity management, wit...
Doutor
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Grenier, Aline M. "Influence of selected endomycorrhizal fungi and phosphorus fertilization on the growth and mineral nutrition of onion grown in newly reclaimed organic soil." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69533.
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Onions are highly responsive to endomycorrhizae and improved plant growth is among the benefits associated with this symbiosis, particularly in low phosphorus soils. Although this crop is grown extensively in organic soils, few studies have been conducted on these. Onion plants (Allium cepa L. cv. Norstar) were inoculated with Glomus aggregatum Schenck & Smith, Glomus clarum Nicolson & Schenck, Glomus fasciculatum Gerdemann & Trappe, Glomus intraradix Schenck & Smith and Glomus versiforme (Karst.) Berch and grown in the field and under controlled conditions to evaluate their efficiency in newly reclaimed organic soil of low P fertility. Three species were selected to evaluate the effects of introduced endomycorrhizal fungi effects and P fertilization (equivalent to 0, 24 and 48 kg P ha$ sp{-1}$) on the growth and mineral nutrition of onion plants.Introducing endomycorrhizal fungi in non-sterile soil did not affect the growth and mineral nutrition of onion. Crop maturity was advanced when plants were inoculated, however. Increasing levels of P fertilization did not depress root colonization and onion growth was increased significantly at the highest rate only. These results suggest that higher levels than recommended could be used in this soil. Inoculation in $ gamma$-irradiated (10 kGy, $ sp{60}$Co) soil alleviated excessive Mn absorption by onion plants. Adding P fertilizer depressed growth and root colonization when plants were inoculated with G. clarum and G. intraradix and was related to the low irradiance levels used in this study. G. versiforme appeared to be the most efficient of the introduced species.
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Allardice, Roderick. "Does the application of vermicompost solid and liquid extracts influence the growth, N-nutrition and soil microbial diversity of the legume, Lupinus angustifolius?" Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/98107.
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Thesis (MSc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Vermicomposts (VCs) are the solid excreta of earthworms, known to contain plant available nutrients, large amounts of microbial life and diversity, and plant growth regulating hormones. VCs may play an integral role in the nitrogen nutrition of Lupinus angustifolius and function to reduce the reliance of legume crops on chemical fertilizers. Furthermore, the effects of the combination of VC solids and VC teas on legume growth and N nutrition, is unknown. The aim of the present study was to determine the role of varying concentrations of chicken manure VC, with and without the additions of varying VC tea concentrations, on the substrate bacterial functional diversity, plant biomass and N nutrition of the legume, L. angustifolius. In the first experiment the plants were grown in pots under glasshouse conditions and VC was substituted into the quartz sand growth media at rates of 5%, 10% and 100%. Furthermore, rhizobia inoculated and non-inoculated groups were established within the VC treatments. The plants were harvested after 30 days and analysed for tissue nutrient concentrations and biomass production. The VC-containing substrates were assessed for wide-spectrum soil analyses, nematode diversity and microbial diversity via Biolog EcoPlates. In the second experiment the plants were grown under similar conditions for 50 days and amended with 5% VC in the growth media as well as 50ml of aerated VC teas. The teas were brewed for 24 hours in concentrations of 4%, 10% and 20% (v/v), with molasses and kelp extract added as sugar sources. The combined treatments of 5% VC and rhizobia inoculation yielded the greatest biomass response. Furthermore the addition of VC allowed for bacterial nitrogen fixation within non-rhizobia treatments. However, changes in VC concentration had no effect on bacterial guild structure but were found to effect nematode funtional diversity. The additions of VC teas to soil media containing 5% VC had no effect on biomass production but were found to influence bacterial nitrogen fixation. Lower concentration teas increased BNF while the 20% tea reduced this parameter significantly over 50 days. The 20% tea also contained significantly greater bacterial functional diversity than the 5% and 10% teas. The findings of study indicate that the combined treatment of VC solids and teas do not increase the plant biomass of L. angustifolius, but that the additions of 20% teas result in greater microbial diversity in the soil. This in turn may lead to increases in soil fertility. Furthermore, additions of high concentration vermicompost teas (20%) shift the dependence of the plant from atmospheric N sources to soil N sources.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar
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Vikas, Vishaw [Verfasser]. "The Impact of Organic Manures on the Soil Quality. A study on Organic Nutrition in Crop Rotation of Okra-Dhaincha-Broccoli / Vishaw Vikas." München : GRIN Verlag, 2020. http://d-nb.info/1207000302/34.
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