Dissertations / Theses: 'Fertilizers'

1

Knowles, Tim C., Paul Artz, and Chip Sherrill. "Preplant Micronutrient Fertilizers for Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/197269.

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Micronutrient fertilizers including zinc, boron, copper, and manganese in their sulfate forms were broadcast applied and incorporated preplant to determine their effects on lint yield of upland cotton.

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2

Xie, Rongjing. "Animal manures and urea as nitrogen sources for corn production in Québec." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64482.

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3

Fathi, Ghodratollah. "Nitrogen responsiveness in barley." Title page, table of contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phf2524.pdf.

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4

Fan, Mingxiang. "Urea and acidic phosphate interactions in fertilizer microsites and their effect on corn (Zea mays L.) yield and nutrient use efficiency." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41334.

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Fertilizer applications of urea and triple superphosphate (TSP) suffer from low efficiency for corn production. Band or broadcast application of urea with acidic-P fertilizers may increase fertilizer efficiency. Urea and acidic-P fertilizer interactions in soil-fertilizer microsites were investigated using two Quebec soils. Adding acidic phosphates such as TSP and monoammonium phosphate (MAP) to urea reduced pH in microsites, urea hydrolysis, NH$ sb3$ volatilization, and increased soil NH$ sb4$- and NO$ sb3$-N contents. Ammonia loss decreased as P$ rm sb2O sb5$: urea-N ratios increased. Adding urea to P fertilizer increased soil pH and P sorption when using CaCl$ sb2$ as the electrolyte. Urea application increased 0.5 M NaHCO$ sb3$ extractable P. Banding urea with TSP caused dissolution of organic matter in soils, and increased P diffusion and P concentration in soil solution sampled with filter paper or in 1 M KCl extraction. Two years of field experiments demonstrated that banding urea with TSP or MAP increased soil extractable P (Mehlich-3), N and P nutrient uptake, plant growth and development of corn. Greater P fertilizer efficiencies and higher yields were achieved by banding urea-acidic P fertilizers.

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5

Smith, Leslie Owen 1960. "Effect of broadcast phosphorus on alfalfa yield and quality." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/558068.

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6

Rafle, Abdirashid Dulane 1961. "NITRATE-NITROGEN AND TOTAL NITROGEN CONCENTRATION IN GRAIN SORGHUM (SORGHUM BICOLOR (L.) MOENCH) AS RELATED TO NITROGEN FERTILIZATION." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291249.

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7

Silva, Marciela Rodrigues da. "Modelo determinístico para estimação da adubação nitrogenada na cultura do milho para grãos e silagem." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/221.

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Com o objetivo de avaliar a necessidade de adubação nitrogenada para a produção de grãos e silagem e um modelo matemático de estimação da produtividade potencial e deplecionada na cultura do milho, foi conduzido um experimento utilizando quatro híbridos de milho (AG30A86, AGN20A55, CD308 e AG30A91)avaliados em oito níveis de adubação nitrogenada. O experimento foi realizado na Universidade Tecnológica Federal do Paraná – PR e o delineamento experimental utilizado foi o de blocos ao acaso com parcelas subdivididas, sendo as doses de N (0, 60, 120, 180, 240, 300, 360 e 420 kg ha-1) aplicadas nas parcelas principais e os genótipos semeados nas subparcelas. As variáveis analisadas no experimento a foram: o índice de área foliar, as características fitotécnicas, os componentes do rendimento, a exportação de nutrientes e os caracteres bromatológicos dos genótipos de milho destinados a produção de grãos e silagem. Em relação ao modelo matemático, as estimativas de produtividade potencial e deplecionada de grãos e silagem de milho, basearam-se nos valores diários de temperatura, insolação, radiação solar, pressão atmosférica e precipitação, para o município de Dois Vizinhos – Paraná. As simulações foram realizadas inicialmente utilizando-se um modelo matemático baseado em modelos e informações da literatura (1) e em seguida, propôs-se um modelo alternativo (2), por meio da alteração dos parâmetros de índice de área foliar, graus dia para o florescimento e número de plantas por metro linear, obtidos no experimento realizado. Os dados simulados foram avaliados por intermédio do coeficiente de correlação de Pearson, índice de concordância de Willmott, desvio padrão, quadrado médio do erro e índice de desempenho de Camargo. Em função dos resultados obtidos pode-se concluir que: a adubação nitrogenada altera as características agronômicas e romatológicas avaliadas nos diferentes cultivares. A produtividade de matéria seca da silagem não foi influenciada pelas doses de nitrogênio, porém a produção de grãos foi alterada, sendo a máxima eficiência técnica para a produtividade de grãos (13.059 kg ha-1) obtida com a dose de 146 kg de N ha-1. O modelo alternativo, calibrado com dados experimentais, pode ser utilizado na simulação das produtividades de grãos e silagem da cultura do milho, assim como para estimar as exigências em nitrogênio para a produção de grãos, apresentando maior eficiência e precisão, em relação ao modelo da literatura. No entanto, as estimativas de requerimento de nitrogênio devem sofrer ajustes para adequar o modelo aos dados verificados.
In order to assess the need for nitrogen fertilizer to produce grain and silage and a mathematical model for estimating potential productivity and depleted in the corn crop, an experiment was conducted using four corn hybrids (AG30A86, AGN20A55, CD308 and AG30A91 ) evaluated at eight levels of nitrogen fertilization. The experiment was conducted at the Universidade Tecnológica Federal do Paraná - PR and the experimental design used was randomized blocks with split plots and N levels (0, 60, 120, 180, 240, 300, 360 and 420 kg ha-1) applied in main plots and subplots seeded genotypes. The variables analyzed in the field experiment were: leaf area index,the characteristics of agronomic parameters, yield components, the export of nutrients and bromatological characters of maize genotypes for grain yield and silage. Regarding the mathematical model, estimates of potential productivity and depleted grain and corn silage, were based on the daily values of temperature, solar radiation, solar radiation, atmospheric pressure and precipitation for the city of Dois Vizinhos - Paraná. The simulations were performed initially using a mathematical model based on models and literature information and then it was proposed an alternative model, by changing the parameters of leaf area index, degree days to flowering and number of plants per meter, obtained in the experiment. The simulated data were evaluated by means of the Pearson correlation coefficient, index by agreement of Willmott, standard deviation, mean square error performance index and Camargo. According on the results obtained it can be concluded that: nitrogen fertilization alter the agronomic characteristics and bromatological evaluated in different cultivars. The dry matter yield of silage was not affected by nitrogen levels, but grain production was influenced, and the maximum technical efficiency for grain yield (13059.30 kg ha-1) was obtained with a dose of 146.12 kg N ha-1. The alternative model, calibrated with experimental data can be used in the simulation of grain and silage yields of maize, as well as to estimate the nitrogen requirements for the production of grains, with greater efficiency and accuracy, compared to the usual model of the literature. However, estimates of nitrogen application should be adjusted to fit the model to actual data.

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8

Fleming, Nigel Kevin. "Polyphosphates and microbial uptake of phosphorus : studies with soil and solution culture." Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09A/09af598.pdf.

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9

Badra, Abdo. "Effects of potassium, magnesium, and sulfur fertilization on corn grain and silage yields in a high nutrient soil." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60449.

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The effects of added potassium, K, magnesium, Mg and sulfur, S on corn grain and silage yields were investigated in the field for two years.
Due to high nutrient soil, K, Mg and S had no effects on corn grain and silage yields. However, there were trends observed in the treatment effects that were significant. Added K at 240 kg K$ sb2$O/ha increased grain yield over zero kg K$ sb2$O/ha in 1983 and Mg at 60 kg/ha increased grain yield over 30 kg/ha in 1984. In silage, 240 kg K$ sb2$O/ha increased yield over 120 and zero kg K$ sb2$O/ha in 1984. Although there was no K by Mg interaction, there was a need for added Mg to achieve higher yields.
The cumulative effect of fertilizer S at 50 kg/ha significantly reduced silage yield in 1984 over zero S treatment indicating that fertilizer S was unnecessary for corn growth by reason of high levels of soil S and sufficient S provided from precipitation and air dry deposition. S had no interaction with K and Mg because there was no need for fertilizer S to increase yields.
The antagonistic association between K and Mg was seen at the seedling, tasseling and silking stages.
There was an indication of a K by S interaction which was expressed at different stages of growth, but this effect was not evident for dry matter yields.

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10

Campbell, Clayton Marshall Fulton John Patrick Zech Wesley C. "Evaluating spinner-disc technology for the distribution of poultry litter." Auburn, Ala, 2009. http://hdl.handle.net/10415/1581.

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11

Spivak, I. S., and L. P. Iarmak. "Methods of protection (pelleting) of nitrogen fertilizers." Thesis, Сумський державний університет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/28676.

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12

Якушко, Сергій Іванович, Сергей Иванович Якушко, Serhii Ivanovych Yakushko, and I. S. Spivak. "Methods of protection (pelleting) of nitrogen fertilizers." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/25807.

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13

Yusran, Fadly Hairannoor. "Triple superphosphate and urea effects on availability of nutrients in the fertilizer band for soybean (Glycine max L.) growth with emphasis on molybdenum." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69710.

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Fertilizer applications of urea and triple superphosphate (TSP) may affect availability of plant nutrients in the soil through alteration of soil pH and sorption-displacement effects. The objectives of this experiment were to evaluate urea and TSP effects on nutrient availability to soybean (Glycine max L.). Field experiments were carried out on three Quebec soils; a Chicot sandy clay loam (Gleyed Melanic Brunisol), an Ormstown silty clay loam (Luvic Gleysol) and a Ste. Rosalie clay (Humic Gleysol). Three levels of TSP (0, 40, 80 kg $ rm P sb2O sb5 ha sp{-1}),$ and three levels of urea (0, 25, 50 kg N ha$ sp{-1})$ were incubated in the field and sampled at 4, 8, 12, and 16 weeks. Added TSP increased extractable P and decreased NO$ sb3$-N. Overall, alterations in nutrients other than N and P with added TSP or urea were not agronomically significant. There was increased concentration of N, P and Mo in soybean in some soils due to TSP application. Added urea increased Mg concentration in soybean. The concentration and uptake of Mo was positively correlated with soil extractable P and Mg. Consequently, application of TSP and urea together improved Mo uptake in the Chicot soil, while in slightly acid soils, Ormstown and Ste. Rosalie, TSP alone increased Mo uptake.

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14

Rajabipour, Ali. "Effects of Ca, K and water table depth on tomato mechanical properties." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39984.

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Two series of tests were performed in summer 1993 and repeated in summer 1994 to investigate effects of potassium, calcium and water table depth on mechanical properties of tomato fruit. In the first group of tests five mechanical properties stress, strain, ER (ratio of stress to strain at break), energy and toughness were calculated from the force-deformation curve obtained by compression of pericarp disks taken from tomato fruits (cv New Yorker) at the breaker stage. In the second group of tests force, deformation and energy were obtained from puncture tests on whole tomato fruit. The textural parameters were used to compare the effects of the potassium, calcium and water level depths on the mechanical properties of tomatoes. Results showed the effects of calcium and water table depths on the mechanical properties were significant. Tomato fruits exposed to increasing moisture stress levels by increasing water table depth exhibited increased firmness. Increased application of calcium also resulted in increased firmness. Application of different potassium levels had in general no significant effect on breaking stress, strain, ER, energy and toughness of tomato fruit pericarp.
A new method of measuring skin strength of tomatoes is described. The method, refered to as loop method, overcame the problems with the existing method using mechanical grips. Further, the loop method was applied to measure the effect of potassium and calcium on skin strength of tomato. Using the loop method, data were collected on relaxation of tomato skin (epidermis). A computer program was written to model th tensile stress relaxation behaviour of tomato skin. The program was employed to calculate linear and non-linear coefficients of a relaxation model. The fitted values were in a very good agreement with experimental data (R$ sp2>$0.99).

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15

Ippersiel, Denis. "The effect of foliar nitrogen fertilization on nitrogen distribution, yield and protein quality of forage corn /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63798.

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16

Sprinkle, Amy Lyn. "Nutrient management on golf courses in Delaware." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.01Mb, 155 p, 2005. http://wwwlib.umi.com/dissertations/fullcit/1428197.

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17

Maiga, Alpha S. "An economic analysis of nitrogen fertilization regimes in Virginia." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-02022007-133634/.

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18

Ahmed, Sabah Kedar. "Yield, dry matter production, and nitrogen uptake of drip irrigated cotton." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/191143.

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The study consisted of two experiments conducted over two growing seasons. Urea ammonium nitrate was used as a source of N at rates of 50, 75, 100 and 150% of levels estimated to be ideal for maximum yield of cotton (Gossvpium hirsutum L.). The nitrogen fertilizer was applied through a drip irrigation system. The yield of seed cotton, flowering pattern, boll set, plant N uptake, and dry matter production were studied in relation to four N fertilizer rates and two plant populations in the 1984 study. Yield of seed cotton, plant N uptake and dry matter production were studied in relation to four N rates, three seeding rates, and three cotton cultivars in the 1985 study. Petiole nitrate patterns were studied both seasons. The effect of N applications on seed cotton yield was dependent upon the initial soil N and the yield possibility. In this study the lower rate of N appeared to be sufficient for the yields obtained. Thinning resulted in reduction of the total number of flowers and significantly decreased yield, but percent boll set was not affected. Nitrogen additions significantly increased plant N uptake and dry matter production as well as petiole NO₃-N levels during the growing season. The N need of cotton under drip irrigation was determined throughout the growing season by using petiole analysis. The levels of petiole NO₃-N for N sufficiency and deficiency which are accepted under furrow irrigation cotton were shown to be applicable for drip irrigated cotton. Yield of DPL-775 and DPL-90 cotton cultivars was significantly higher than that for DPL-41 cotton cultivar in 1985.

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19

Tekin, Elif. "Anaerobic Ammonium Oxidation in Groundwater Contaminated by Fertilizers." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23956.

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Anaerobic ammonium oxidation (anammox) is a pathway that has been known for almost 2 decades, but few studies have investigated its importance in natural groundwaters. This thesis investigated the presence of anammox cells and the groundwater geochemistry of 2 sites (Elmira and Putnam) in southwestern Ontario where groundwaters are contaminated with high levels of nitrate and ammonium. Fluorescence in situ hybridization (FISH) was used to quantify the relative abundance of anammox cells in these waters. Our results showed that anammox cells could be detected in many wells at both sites and that their relative abundance varied between 0.45 and 4.81 % at the Putnam site, whereas it ranged between 0.8 to 8.4 % at the Elmira site. These values are within the same range as those obtained for marine and freshwater environments where anammox cells have been detected. In addition, indirect observations point to the fact that N cycling at the 2 sites might be linked to Fe and Mn reduction, but additional experiments are needed. In summary, our results corroborate the findings of N-labeled microcosm experiments which demonstrated that anammox was an important pathway of N cycling in those groundwaters and molecular analyses that detected important anammox organisms at the same sites.

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Pandithagedara, Weeraratne Balasuriya. "Rubber urea composites as slow release nitrogen fertilizers." Thesis, University of Ulster, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243629.

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21

Shandyba, A. B., D. M. Shpetny, and A. V. Vasilushenko. "Production of environmental fertilizers by Ukrainian phosphate industry." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/46861.

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The fertilizer industry uses a wide range of production technologies, which are considered under engineering and environmental aspects. The traditional composition ration of N, P, K had changed to more using the additional microcomplex and organic components. The objective of this study was to evaluate agronomic and environmental effectiveness of the new mineral-organic generation fertilizers by comparing it with the other fertilizers such as the super phosphate (as P source) or ammophos of traditional trade marks.Technical feasibility of the phosphate fertilizer industry has been demonstrated by using native raw materials and local wastes.

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22

Mupondi, Lushian Tapiwa. "The effects of goat kraal manure, sewage sludge and effective microorganisms on the composting of pine bark and the nutritional value of the composts." Thesis, University of Fort Hare, 2005. http://hdl.handle.net/10353/d1001008.

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23

Noellsch, Adam J. "Optimizing crop N use efficiency using polymer-coated urea and other N fertilizer sources across landscapes with claypan soils." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5643.

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Thesis (M.S.)--University of Missouri-Columbia, 2008.
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 September 12, 2008) Includes bibliographical references.

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24

More, Ketseemang. "Response of cabbage (Brassica Oleracea Var Capitata) transplants to nitrogen, phosphorus and potassium nutrition." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-09212007-133240.

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25

Woldetsadik, Kebede. "Shallot (Allium cepa var. ascolonicum) responses to plant nutrients and soil moisture in a sub-humid tropical climate /." Alnarp : Dept. of Crop Science, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a367.pdf.

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26

Zhang, Tiequan. "Chemical behavior of phosphorus over time in fertilized soils." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34486.

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Fertilizer P accumulates in soils, with potential for movement to waterways, causing eutrophication. Fertilizer P reactions in monoculture corn (Zea mays L.) production over time will determine environmentally sound soil management practices. Soil P changes over time were determined on a Chicot sandy clay loam (Grey Brown Luvisol) and a Ste. Rosalie clay (Humic Gleysol). Fertilizer P was added at 44 and 132 kg P ha$ sp{-1}$ and to the Chicot soil only, manure containing 60 kg P for the first five years. Mehlich-3 (M3) extraction, soil P fractionation, $ sp{31}$P NMR analysis, P in leaching water, and path analysis were measured. Added P increased M3 P more when manure was also added, and in clay soils. To increase M3 P by 1 kg ha$ sp{-1}$ required from 3.6 to 8.1 kg ha$ sp{-1}$ fertilizer P, and when "net" fertilizer additions were used, fertilizer required was from 1.8 to 5.3 kg P ha$ sp{-1}.$ Moderately labile organic P (Po) decreased at 0 added P. With P at the rate of plant removal, inorganic (Pi) and Po fractions were unchanged. Excess P increased labile P and resistant P through moderately labile Pi. More P remained in labile Pi fractions when manure P was added, or in the soil with the higher clay content. Soil organic P levels increased upon fertilization only in the sandy loam soil. Labile and moderately labile Po could be estimated using monoester phosphate values determined by $ sp{31}$P NMR. Inorganic P values in gravitational water increased above 0.05 mg P L$ sp{-1}$ when soil labile Pi increased above 108 mg kg$ sp{-1}$ in the sandy loam soil and 69 mg L$ sp{-1}$ in the clay soil. Thus soil P movement was related to inorganic P additions. Increased fertilizer P did not increase organic P leaching losses. Fertilizer P in corn production may result in groundwater eutrophication.

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Feland, Calli. "Nitrogen Fertilizer Types and Application Timing on Hard Red Spring Wheat Productivity and Grain Protein." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/29209.

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The balance of improving hard red spring wheat (Triticum aestivum L. emend Thell) yield while maintaining grain protein concentration continues to be a challenge in agriculture. The objective of the field research was to evaluate N fertilizer types, additives, rates, and application timing to find N management strategies that improved the efficiency of the applied N with regards to both grain protein and yield. Another aspect of this study was to determine if ground-based active sensor data can predict grain yield and/or protein content. Fertilizer treatments consisted of 2 application timings, 3 sources of N, 3 rates of N, and 2 additive types. Spring applications improved grain protein and yield compared to fall applications. Polymer coated urea shows promise in improving grain protein over urea alone. However, profitability is dependent on environmental factors that may influence N availability, as well as prices at the time that the grain is marketed.
Minnesota Wheat and Promotion Council

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Chen, Jiansheng. "Effects of added nitrogen and potassium on selected soil properties and on yield and nutrient uptake of silage corn." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59948.

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An incubation study was conducted to evaluate the effects of added urea, NH$ sb4$Cl, and KCl on fixation of NH$ sb4 sp{+}$ and K$ sp{+}$. A field study was carried out to observe the effects of rates and methods of added urea and KCl on the forms and distribution of N and K in soils, and on yields and nutrient uptake of silage corn.
Generally, the fixation of NH$ sb4 sp{+}$ was increased by added N but reduced by added K and vice versa. One exception was that added K increased NH$ sb4 sp{+}$ fixation when NH$ sb4$Cl was the N source. In comparison with NH$ sb4$Cl, urea resulted in greater K$ sp{+}$ fixation but less NH$ sb4 sp{+}$ fixation.
Band placement of urea and KCl showed apparent accumulation of NH$ sb4$-N and NO$ sb3$-N, and exchangeable K$ sp{+}$ in the fertilizer bands, particularly early in the growing season. On the other hand, band placement resulted in lower levels of available N and K in soil between the bands in comparison with broadcast.
Yields of silage corn and nutrient uptake values were increased by N and K fertilizers, except for one soil in the first year. Band placement of urea was superior in the case of frequent and light rainfall but inferior with dry surface soil conditions followed by a relatively large rainfall 3 or 4 days after application. In the latter condition, banding K resulted in less yields on one soil, and banding the two fertilizers together further reduced N utilization on another soil.
Additions of K suppressed Ca and Mg uptake but did not influence N uptake, whereas K uptake was usually enhanced by added N.

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Solontsi, Mhlangabezi. "The response of maize to selected ratios of organic fertilizers mixed with inorganic fertilizers in Ndlambe Local Municipality, Eastern Cape, South Africa." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020902.

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The majority of small-scale farmers in the Eastern Cape apply inadequate quantities of manure, inorganic (NPK) fertilizer and Gromor as lone fertilizers or tend to mix manure or Gromor with chemical fertilizers for crops, without any scientific basis (Mkile, 2001). Hence this study – aimed at achieving effective and efficient use of chemical fertilizers, manure and Gromor, either as lone fertilizers or mixed with one another, in maize production – was established. A three-year dry land field experiment, arranged in a RCBD with 3 replicates where cattle manure, chemical fertilizer and Gromor were mixed at different ratios – as treatments FM1 (10 percent fertilizer + 90 percent manure); FM2 (25 percent fertilizer + 75 percent manure); FM3 (50 percent fertilizer + 50 percent manure); MAP (100 percent fertilizer); M (100 percent cattle manure); FG1 (10 percent fertilizer + 90 percent Gromor); FG2 (25 percent fertilizer + 75 percent Gromor); FG3 (50 percent fertilizer + 50 percent Gromor); G (100 percent Gromor) and a control (with nothing applied) – was conducted at the Nolukhanyo agricultural project at Bathurst in the Ndlambe Local Municipality. Maize cultivars PAN 6480 and Sahara were used as test crops. Manure, Gromor and soil were analyzed for their nutrient composition. Data recorded involving number of kernels per cob-1, grain and dry matter (DM) yields for the 2010-11, 2011-12 and 2012-13 seasons, and leaf area index (LAI) – were subjected to Genstat Version 14.1 for statistical analysis. Grain yields of PAN 6480 and Sahara recorded in seasons 2010-11, 2011-12 and 2012-13 were significantly higher (p≤0.05) than those of the controls. In 2012-13, PAN 6480 on treatments FG3 and FG1 produced the highest grain yields (5 327 and 5 107kg ha-1) respectively, while in 2010-11 the highest yield was 3 780kg ha-1. In the 2012-13 season, Sahara on F treatment was the highest with 4 553kg ha-1 whilst there were no significant differences in F and M treatments. Dry matter yields of Sahara were higher than those of PAN 6480 in all seasons. The highest Sahara LAI obtained on FM2 was 5.85 in the 2012-13 season, whereas PAN 6480 had LAI of 4.77 on F treatment, followed by FG3 with 4.72 LAI. PAN 6480 number of leaves for 6 plants in m2 and LAI in week 8 of the 2012-13 season had a positive correlation, r2=0.84. PAN 6480 number of kernels and cob length in the same area correlated quite well (r2 =0.91). Chemical fertilizer corrects the imbalances of nutrients inherent in organic manures and increases both maize grain yields and dry matter yields, and also influences number of leaves and LAI. Treatments FG1, FG3 and FM1 of PAN 6480 resulted in high maize grain yields when planted 13 in late November of the 2012-13 growing season and when water in the soil profile was conserved as a result of good rains received prior to planting. Treatments FG1 (10 percent fertilizer + 90 percent Gromor), FG3 (50 percent fertilizer + 50 percent Gromor) of PAN 6480 produced the highest grain yields (5 107kg ha-1 and 5 327kg ha-1 respectively) in the 2012-13 season, whilst FM1 (10 percent fertilizer + 90 percent manure) gave the highest grain yield (of 4 277kg ha-1) for the same cultivar in the 2010-11 season.

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30

McArthur, David Albert James. "Strawberry and cranberry response to growth regulators and fertilizers." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26450.

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The growth and yield response of strawberry (Fragaria X annassa Duch.) and cranberry (Vaccinium macrocarpon Ait) to various growth inhibitors, but especially to paclobutrazol (PP333), and fertilizers were investigated in glasshouse and field studies. PP333 decreased vegetative growth in a rate-dependent manner in both strawberry and cranberry. PP333 delayed fruit ripening in strawberry and decreased fruit set and fruit size in cranberry. PP333 decreased pollen germination of strawberry. Soil residues of PP333 were biologically active when measured 11 weeks after application in the strawberry study and when measured after 50 weeks in a cranberry study. In a field study with cranberry, PP333 caused a decrease in vegetative growth and an increase in flowering in the next season after treatment. Two-dimensional partitioning was used to account for yield variation from treatment effects on adjusted yield variates. The truss number was the most important contributor to yield variation in the strawberry, but was not affected by treatments. PP333 made a substantial contribution to yield variation in strawberry through its effect on fruit development and ripening. In the cranberry, fruit set was the major contributor to yield variation and PP333 influenced yield substantially through its effect on fruit set. In glasshouse studies, PP333 decreased shoot elongation in cranberry within 3 weeks of application, and increased the number of branches on primary shoots. Buds were formed within 7 weeks of treatment and some of the buds contained flowers. Shoot growth was greater with a high rate of NPK fertilizer than with the low fertilizer rate and was greater in peaty soil than in sandy soil. While bud set was not modified by soil type or fertilizer rate, high NPK fertilizer decreased floral induction. Some effects of PP333 treatment were decreased by gibberellic acid, but generally these effects here not reversed. In a field study with the cranberry, PP333 increased flower bud set for flowering and non-flowering uprights but slightly decreased floral induction for non-flowering uprights.
Land and Food Systems, Faculty of
Graduate

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31

Doerge, Thomas A., Jerome Pier, and Ted McCreary. "Watermelon Response to Soluable and Slow Release Nitrogen Fertilizers." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/214499.

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A field experiment with subsurface drip irrigated watermelon was conducted on a Casa Grande s.l. soil at the Maricopa Agricultural Center in 1992 to evaluate the field performance of two slow release nitrogen (SRN) fertilizers in comparison to a conventional soluble N source, urea, ammonium- nitrate (UAN-32). Single, preplant applications of 0, 100 and 200 lbs N/acre supplied from methylene urea (Nutralenes) or 100, 150 and 3(X) lbs N/acre from a methylene urea-ammonium sulfate mixture (MUAS) were evaluated in comparison to treatments of UAN-32 containing from 52 to 445 lbs N/acre made in five split applications. Yield response to N rates above 100 lbs/acre were similar for all three N sources, indicating that a single, preplant application of a suitable SRN material at an adequate rate could provide N efficiently over the entire growing season. The highest numerical yield (49.3 tons/acre) was obtained with a N rate of 150 lbs N/acre from the MUAS material. Monitoring of petiole nitrate levels throughout the season indicated that N release from the MUAS was more rapid and more complete than from the methylene-urea product. At suboptimal N rates, i.e. < 150 lbs N/acre, split applications of UAN-32 appeared to be somewhat more efficient than the slow-release products.

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32

Van, Niekerk Corrie Maria. "Nitrogen dynamics in sewage sludge and commercial fertilizer enriched soils." Diss., University of Pretoria, 2004. http://hdl.handle.net/2263/24180.

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This study indicated that sewage sludge could be used as an alternative to commercial inorganic fertilizers. It is common practice in South Africa to use agricultural land for disposal of sewage sludge. The disposal of sludge must however be done in a responsible manner to avoid environmental pollution such as nitrate (NO3-) leaching. In South Africa strict guidelines exist regarding sludge disposal, and a maximum of 8 ton ha-1 year-1 (dry mass basis) sludge may be applied. This value was based on possible NO3- leaching, but no equivalent legislation exists for commercial fertilizer that could result in the same harmful effects. In this study the possible pollution hazard in terms of NO3- leaching from sewage sludge was investigated and compared to commercial fertilizer. An incubation trial was done to determine the mineralization rate of sludge and fertilizer. The rate at which inorganic N, NO3- and NH4+ was produced from sewage sludge was measured during this experiment. Sludge was applied at three different loads: 5, 10 and 20 ton dry ha-1. Commercial fertilizer was also applied on three different levels and each level was equivalent to 30% of the N content of the corresponding sludge treatments. It was found that in the sludge treatments the NH4+ levels immediately increased possibly due to microbial activity. The NH4+ levels reached a maximum on day 7, with a production rate of 14, 26 and 60 mg kg-1 NH4+ for the 5, 10 and 20 tondry ha-1 treatment, respectively. After day 7, the production rate decreased while the NODissertation (MSc)--University of Pretoria, 2006.
Plant Production and Soil Science
unrestricted

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33

Norrish, Shane A., University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "Soil and water interactions controlling wheat crop response to phosphorus fertiliser in north-western New South Wales." THESIS_CSTE_EAG_Norrish_S.xml, 2003. http://handle.uws.edu.au:8081/1959.7/613.

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This thesis examines the response to P fertiliser by wheat crops growing in the vertosol soils of the low rainfall areas of the northern grain zone of eastern Australia. Farmers in this region depend on water accumulated from rainfall over a fallow period and stored in the subsoil to increase wheat grain yield beyond that normally achievable from in-crop rainfall and to decrease the production risks due to rainfall variability. The large variability in stored water, seasonal rainfall and subsoil properties result in extremely varied yield and yield responses to P fertiliser between seasons and between sites. Finally, as a practical guide to predicting wheat response to P fertilizer: 1/. current sampling strategies of determining P only in the surface 10 cm appear to be adequate for soils with bicarbonate P concentrations greater than 15 mg/kg. 2/. For soils with lower concentrations in the surface, sampling of 80 cm is recommended. Crops with a mean concentration of bicarbonate P greater than 7 mg/kg between 10 - 80 cm are unlikely to respond to P fertiliser. 3/. No increase in profitable grain yield response was found for fertiliser applications greater than 10 kg P/ha.
Doctor of Philosophy (PhD)

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34

Painchaud, Jacques. "L'azote du sol et la fertilisation de la pomme de terre." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0016/MQ37155.pdf.

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35

Morris, Jerry Whitaker. "Influence of nitrogen fertilization and leaf management on nitrogen use effeciency and agronomic performance of mammoth cultivars of flue-cured tobacco." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/44303.

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36

Razmjoo, Ghalaie Khorshid. "Effect of potassium, sulfur, boron, and molybdenum fertilization on alfalfa production and herbage composition /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487260859495673.

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37

Mohamed, Abdellatif Abdellatif 1956. "Response of cotton to N and water applied via a trickle irrigation system : growth, yield, and nutrient uptake." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191128.

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The crop growth rate (CGR); the relative growth rate (RGR); seed yield; plant uptake of N, P, K, Ca, Mg, Fe, and Na; and the water use efficiency (WUE) were studied in relation to N fertilizer and water application rate interactions in trickle-irrigated cotton. Increasing water application rate significantly increased CGR, but no significant differences were detected among the RGR values at the various water levels. Nitrogen fertilizer additions significantly increased the CGR. Nitrogen and water applications significantly increased seed yield, however, the effect of the interaction between N and water was not significant. Water levels had a positive significant effect on the cotton reproductive growth. Increased N and water significantly increased total N-uptake by cotton plants. Nitrogen additions significantly increased N% of leaves, burrs and seed. However, N% of stem was significantly reduced with high N applications. Total uptake of P, K, Ca, and Mg significantly increased with the increased application of N and water. Addition of 1.2 consumptive use (Cu) irrigation rate significantly increased P% in cotton stems, however, K% in stem was reduced. The irrigation rate of 0.9 CU and 1.2 CU significantly increased Mg% in both leaves and stems. Nitrogen application rates of 224 and 336 kg N/ha significantly decreased Mg% in leaves and stems. Increasing the irrigation rate from 0.9 CU to 1.2(1.3) CU reduced the WUE by cotton plants. However, WUE appeared to increase as N fertilizer increased up to 33 kg N/ha with water level of 0.9 CU.

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38

Musa, Ali El-Toum Hassan. "Effects of molybdenum, zinc and rhizobium inoculation on growth and yield of groundnut (Arachis hypogaea L.)." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388472.

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39

Antoniadis, Vasileios. "Heavy metal availability and mobility in sewage sludge-treated soils." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298663.

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40

Zhang, Feng 1962. "Effects of N formulation, application rate, and application time on corn yield and quality in eastern Canada." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61039.

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An experiment was conducted to investigate the effects of N formulation, application rate, and application time on corn yield and quality under Eastern Canadian conditions, to evaluate the hypothesis that application of N will increase corn grain yield and protein concentration without decreasing the total energy content. Three N formulations, each with the rates of 90, or 180 kg ha$ sp{-1}$ were applied at different times. The results indicated that the grain yield increased with increasing N fertilizer rate and with increasing numbers of N application times. N application significantly increased grain protein concentration, on both a per kernel and a dry matter basis, and protein yield. Such as, N application increased the averaged protein concentration, on a dry matter basis, of corn grain by about 8.40% as compared to the control. The protein concentration was not affected by the number of N application times before the plants were 90 cm high. Neither lipid nor non-structural carbohydrate concentration, on both a per kernel and a dry matter basis, were significantly affected by N application in most of the location-years. In addition Near infrared reflectance (NIR) was used to determine the lipid concentration in the aerial corn tissue at different growth stages. The correlation coefficients between the standard analytical method and the NIR method of lipid concentration were all above 0.95, and were significant at 0.01 level.

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Lee, Cheuk-hung. "The growth and mineral contents of vegetables treated with composed livestock waste /." Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20667395.

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42

Miransari, Mahabadi Mohammad Reza. "Development of a nitrogen soil test for fertilizer requirements for corn and wheat production in Quebec." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23415.

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One must consider the effects of both soil N and fertilizer N, if rates of N-fertilizer application are to be optimized and NO$ sb3 sp-$ leaching into groundwater be controlled. Objectives were (1) to determine soil $ rm NO sb3 sp-$-N and NH$ sb4 sp+$-N, soil total N, and N fertilizer levels and corn and wheat yields; and, (2) to determine soil sampling times and depths for N analyses that correlated with yields and fertilizer N response. Soil samples taken at seeding and postseeding were analyzed for NH$ sb4 sp+$-N and NO$ sb3 sp-$-N, and for total N in 29 wheat sites and 44 corn sites fertilized with four rates of N. N-Trak (quick test) and laboratory methods were employed to measure soil NO$ sb3 sp-$-N. A significant correlation was found between N-Trak and laboratory methods (R$ sp2$ = 0.61$ sp{**}$ for corn and 0.89$ sp{**}$ for wheat). Compared to the laboratory method, N-Trak overestimated soil NO$ sb3 sp-$-N. Soil NO$ sb3 sp-$-N levels increased upon drying. In some cases soils showed an increase in soil NO$ sb3 sp-$-N from seeding to postseeding. Wheat yields and wheat grain N uptake were better correlated with soil NO$ sb3 sp-$-N at seeding than at postseeding. For corn, yields and grain uptake showed a higher correlation with soil NO$ sb3 sp-$-N at postseeding. Corn regression models predicted 180 to 240 kg ha$ sp{-1}$ of N fertilizer to obtain optimum economic yields and 0 to 40 kg ha$ sp{-1}$ N for wheat. Soil total N was not correlated with corn yields as highly as soil NO$ sb3 sp-$-N. Soil NO$ sb3 sp-$-N can be used as an indicator of fertilizer N requirements for corn and wheat in Quebec.

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43

Absher, Karen Lynne. "Nitrogen utilization in tall fescue (Festuca arundinacea Schreb.) pastures fertilized with nitrogen or grown with alfalfa (Medicago sativa L.) or red clover (Trifolium pratense L.)." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44100.

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Use of legumes as an alternative to nitrogen (N) fertilization in pasture management improves forage quality and animal performance and has been suggested to reduce the potential for environmental pollution. "Kentucky 3l" tall fescue fertilized with 160 kg N ha-1 yr-1 (split application) was compared to tall fescue grown with alfalfa or red clover in a 5-yr pasture experiment on a mixed Typic Hapludult. During yr 6, effects of N fertilization or the legume on soil N, forage N concentration, yield, botanical composition, N intake by esophageally fistulated steers grazing the pastures and N utilization by wethers fed the harvested forages were investigated. Soil ammonium was higher (P â ¤ .01) in the A and B horizons in the tall fescue-red clover pastures compared to the other treatments and nitrate was lower (P â ¤ .05) in the A horizon, but concentrations differed (P â ¤ .01) by date. Nitrate in the A horizon averaged 2.65, 1.38 and 2.21 ppm for tall fescue-N, tall fescue-red clover and tall fescue-alfalfa, respectively. In the B horizon, average soil NO3 was .43, .23 and .53 ppm for tall fescueâ N, tall fescue-red clover and tall fescue-alfalfa, respectively. Tall fescue-alfalfa pastures were higher (P â ¤ .01) in percentage legume than tall fescue-red clover, overall, but differed by date (P â ¤ .01). Alfalfa was generally higher (P â ¤ .05) in N concentration than red clover. Total kg N accumulated ha^-1 in above-ground herbage was higher (Pâ ¤ .05) for the grass-legume mixtures than N-fertilized tall fescue. Esophageally fistulated steers grazing stockpiled tall fescue-alfalfa selected forage higher (P â ¤ .05) in N concentration than steers grazing the other pastures. Stockpiled tall fescue-alfalfa fed to wethers in a metabolism trial was higher (P â ¤ .01) in N concentration, dry matter digestibility (DMD), apparent N absorption, and N retention than the other treatments. All treatments differed, with wethers fed tall fescue-red clover having the lowest DMD, apparent N absorption and N retention. Wethers fed tall fescue-alfalfa and tall fescue-red clover had higher blood urea N then those fed tall fescue-N. Results of this research demonstrate that soil NO₃ concentrations were low for all three forage treatments and would not contribute to ground water contamination. Legumes supplied adequate N to achieve yields similar to tall fescue fertilized with N and increased N production ha^-1 in the above ground biomass. Digestibility and utilization of the N in stockpiled tall fescue were improved by inclusion of alfalfa but not red clover.

Master of Science

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44

Митова, И. И., Ю. А. Ахмед, and Р. Чутуркова. "Оценка факторов рабочей среды при производстве фосфорных удобрений." Thesis, Сумский государственный университет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/48081.

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Сделана оценка факторов рабочей среды при производстве фосфорных удобрений в "Агрополихиме" АД – в цехе "Фосфорная кислота" и в цехе "Тройной фосфат". Ведущее место по своей выраженности занимают химические вредные факторы. Кроме этого, внимание направлено на физико- химический фактор пыли и физический фактор шума.

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45

Campbell-Nelson, Katie. "Assessment of ammonia volatility from fall surface-applied liquid dairy manure." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/273/.

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46

Kuraya-Ziyadeh, Natalie. "A Behavioral Analysis of Households Using Reclaimed Water in Irrigation: Case of Pinellas County, Florida." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7319.

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In order to tend to the world’s dwindling freshwater supplies, sustainable alternative methods need to be integrated in order to keep up with the world’s increasing demand. Reclaimed water (RW) is one of the sustainable methods adopted by some Floridian cities such as Tampa, Tallahassee, and St. Pete that provide an alternative water source for non-potable uses. However, despite this alleviating effect RW has on freshwater supplies, it is crucial to recognize the potential harm it poses on neighboring waterbodies due to the residual contaminants it still contains, including Nitrogen (N) and Phosphorous (P). As such, studying residents’ knowledge and behavior about RW provides an insight into certain behavioral trends that potentially explain elevated levels of N and P in certain waterbodies. This study surveyed households living in the vicinity of Joe’s Creek Watershed and are using RW in irrigation provided by Pinellas County Utilities Department (PC) and the City of St. Pete Water Resources Department (SP). After looking at these residents’ yard practices, no harmful behavioral trend was observed to explicate the health of neighboring waterbodies. RW users are aware of the irrigation regulations set for them. However, weakness in information communication between city and County officials and RW users on fertilizer use and regulations was recorded. It is recommended that the city of St. Pete revisits their loose regulations on RW and the irrigation schedule set for their customers. More outreach material on fertilizer application and regulations need to be made available and accessible to the public.

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47

Lovas, Sarah. "Laboratory and Greenhouse Evaluation of FeEddha Fertilizers of Differing Quality." Thesis, North Dakota State University, 2013. https://hdl.handle.net/10365/27101.

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Commercial iron ethylene diamine di(hydroxyl phenyl acetic acid) (FeEDDHA) fertilizers containing the same Fe percent and applied at the same FeEDDHA rate control Fe deficiency chlorosis (IDC) differently due to differing ortho, ortho FeEDDHA (o,o-FeEDDHA) concentrations. This study: 1) determined the effect of o,o-FeEDDHA concentration on controlling IDC in soybeans (Glycine max L. Merr.); and 2) developed a soil-stability test using a simple colorimetric analysis method to determine the relative quality of soil-applied FeEDDHA fertilizers. A greenhouse experiment was conducted where nine FeEDDHA fertilizers were applied at two FeEDDHA rates. The soil-stability test compared these fertilizers with two incubation methods which utilized three soils and four incubation times, and extracts were analyzed by two methods. The results of these experiments suggest that soil-applied FeEDDHA fertilizer quality is contingent upon its o,o-FeEDDHA concentration, and the fertilizer quality can be determined by a soil-stability test with a colorimetric analysis method.
North Dakota Soybean Council
North Dakota Experiment Station

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48

Walters, Cory G. "Producer opportunism and environmental impacts of crop insurance and fertilizer decisions." Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Dissertations/Fall2008/C_Walters_090808.pdf.

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49

Campbell, Richard John. "Effect of nitrogen fertilization on the physiological damage and subsequent recovery of mite-infested apple leaves /." This resource online, 1988. http://scholar.lib.vt.edu/theses/available/etd-04122010-083649/.

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50

Pholsen, Suradej. "Effects of nitrogen, potassium and organic matter on growth, chemical components and seed yields of IS 23585 forage sorghum cultivar." Thesis, University of Hertfordshire, 2003. http://hdl.handle.net/2299/14178.

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Sorghum is considered to be of African origin and subsequently spread to most countries in tropical and subtropical regions. Sorghum has outstanding resistance against drought conditions. Grain and fodder from sorghum plants have been used for man's and animals' consumption respectively for many decades. Experiments were conducted on Yasothon soil series (Oxic Paleustults) in Northeast Thailand, this is considered a poor soil. Growth parameters of sorghum were affected most by nitrogen chemical fertiliser followed by potassium chemical fertiliser. An increase in nitrogen level increased growth parameters and seed yields/ha of the sorghum plants whilst an increase in potassium also increased growth parameters and seed yields but to a lesser extent. High application rates of both nitrogen and potassium were required to achieve high total dry weights and seed yields/ha. Fermented cattle manure significantly increased growth parameters of the sorghum plants and soil properties. were also improved by cattle manure. Total dry weights and seed yields/ha were affected most by seasons and treatments whilst seasons x treatments had highly significant effects on seed yields/ha but not total dry weights/ha. In terms of economic viewpoint, optimum application rates for nitrogen at a range of 300-450 kg N/ha and 100 kg K20/ha for potassium plus 40 tonnes/ha of fermented cattle manure were the recommended rates for optimum above ground total dry weight (15,940-26,282 kg/ha) and seed yield (5,047- 6,374 kg/ha) of IS 23585 forage sorghum cultivar on Yasothon soil series. An increase in nitrogen fertiliser application increased estimated crude protein (CP) of the sorghum plants whilst potassium did not. Both nitrogen and potassium had no Significant effects on acid detergent fibre (ADF), neutral detergent fibre (NDF), and dry matter degradability (DMO). However, seasons had significant effects on CP, NDF, ADF, DMD and brix values. Treatments also had significant effects on all components except DMD, and brix values. Seasons x treatments had significant effects on all components except CP and brix values.

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Dissertations / Theses on the topic 'Fertilizers'

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