Дисертації з теми "Internal nitrogen use efficiency"
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Gherli, Hussein. "Nitrogen use efficiency in Brassica napus." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/97639/.
Повний текст джерелаBrown, Tabitha Therisa. "Variable rate nitrogen and seeding to improve nitrogen use efficiency." Thesis, Washington State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10043121.
Повний текст джерелаIncreased nitrogen (N) fertilizer additions to modern agricultural cropping systems will be necessary to feed a growing world population. However, greater nitrogen use efficiency (NUE) is required if agroecosystems are to continue to provide certain ecosystem services (e.g., greenhouse gas emission reductions and water quality goals). The aim of this research was to investigate the role of variable rate N and seeding of winter wheat (Triticum aestivum) for optimizing yield-water-NUE relationships across heterogeneous landscapes. Field plot studies were conducted at the Cook Agronomy Farm (CAF) near Pullman, WA during the 2010, 2011 and 2012 winter wheat harvest years. A randomized complete block split plot N rate x seeding rate experiment with N fertilizer rate as main plot and seeding rate as subplot was employed across three landscape positions. Assessed were evidence of “haying-off”, depletion of available water resources, and the link between yield, protein, and NUE response to landscape by N fertilization rate by seeding rate treatment combinations. A performance classification was developed to evaluate wheat performance with regard to N utilization efficiency (Gw/Nt) and N uptake efficiency (Nt/Ns) components of the NUE.
Evidence of haying-off in winter wheat was medium to high for drier landscape positions, particularly during low precipitation years and likely occurs in these landscapes most years. Treatment impacts on NUE varied by year and landscape but overall NUE decreased by 14 to 22 kg grain yield per kg N supply as N rate increased from 0 to 160 kg N ha-1 across three landscape positions and two site years (2011 and 2012). Target NUE and maximum anthesis biomass could be achieved with a 34 to 68% reduction in typical seeding rates. The NUE-based performance classification was helpful in identifying environmental or management conditions contributing to low or high NUE indicating potential to be used as an evaluation tool. This research also included a policy fellowship focused on N2O emission reductions and greenhouse gas offset credits that could be generated from adoption of variable rate N for wheat and concluded that offset credits alone would not provide enough incentive for adoption of variable rate N.
Ransom, Curtis J. "Nitrogen Use Efficiency of Polymer-Coated Urea." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/3985.
Повний текст джерелаAhrens, Toby D. "Improving regional nitrogen use efficiency : opportunities and constraints /." May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
Повний текст джерелаThennakoon, Mudiyanselage Sakura Dilhani Karunarathne. "Genetic improvement of nitrogen use efficiency in barley." Thesis, Thennakoon Mudiyanselage, Sakura Dilhani Karunarathne (2021) Genetic improvement of nitrogen use efficiency in barley. PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/64211/.
Повний текст джерелаKakkar, Avneet. "Nitrogen Availability and Use Efficiency in Corn Treated with Contrasting Nitrogen Sources." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6886.
Повний текст джерелаZhao, Yun. "Genetic dissection of wheat nitrogen use efficiency related traits." Thesis, Zhao, Yun (2019) Genetic dissection of wheat nitrogen use efficiency related traits. PhD thesis, Murdoch University, 2019. https://researchrepository.murdoch.edu.au/id/eprint/57397/.
Повний текст джерелаHitz, Katlyn. "Breeding for Nitrogen Use Efficiency in Soft Red Winter Wheat." UKnowledge, 2015. http://uknowledge.uky.edu/pss_etds/62.
Повний текст джерелаOgola, J. B. Ochanda. "Improving water use efficiency of maize through proper nitrogen management." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340024.
Повний текст джерелаStadler, Christina. "Nitrogen release and nitrogen use efficiency of plant derived nitrogen fertilisers in organic horticultural soils under glasshouse conditions." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980532159.
Повний текст джерелаNett, Leif. "N use efficiency in field vegetable production systems." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16463.
Повний текст джерелаThe current study dealt with two questions that target potential options to increase the nitrogen (N) use efficiency of agricultural systems: 1) Does long-term organic fertilization affect the decomposition of recently added organic fertilizers? The hypothesis was that effects only occur for recalcitrant organic fertilizers while for readily decomposable organic fertilizers, the fertilization history does not play a role. 2) Can the N balance surpluses in intensive field vegetable production systems be substantially reduced by cultivation of winter catch crops (CC)? The hypothesis was that the N balance surpluses of the investigated two-year crop rotations can be reduced by more than 30 kg N / ha. The first hypothesis was tested by applying organic fertilizers to soils that only differed in organic fertilization history. A greenhouse pot experiment and a laboratory incubation experiment were conducted. The results indicated that fertilization history had effects on the decomposition of farmyard manure and pine bark, not however on the decomposition of readily decomposable cabbage material. Hence, the hypothesis was accepted in that fertilization history effects depended on the type of fertilizer. However, fertilization history effects showed no consistent trend with respect to increase or decrease in carbon (C) and N mineralization and the effects on net N mineralization were minor in magnitude. The second hypothesis was tested by performing field experiments at three sites in Germany. Vegetable crop rotations were set up, testing different types of CC. The results suggested that in spite of high N surpluses in the control treatments (no CC) of 217 kg N / ha, CC reduced the N balance surplus on average by only 13 kg N / ha. Hence, the hypothesis was rejected. The findings further indicated that the transfer of N taken up by the CC to the succeeding crop is a critical step when adopting this technique.
Kage, Henning. "Simulation modelling for improving nitrogen use efficiency in intensive cropping systems." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=977957020.
Повний текст джерелаAl-Habbar, Zaid. "Improve Nitrogen use efficiency of wheat cultivars under Western Australian conditions." Thesis, Al-Habbar, Zaid (2018) Improve Nitrogen use efficiency of wheat cultivars under Western Australian conditions. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/53212/.
Повний текст джерелаDorsey, Nathaniel D. "Nitrogen use efficiency and nitrogen response of wheat varieties commonly grown in the Great Plains, USA." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17618.
Повний текст джерелаDepartment of Agronomy
Nathan O. Nelson
Increasing nitrogen use efficiency (NUE) and nitrogen response in winter wheat could help producers reduce input costs associated with nitrogen fertilizers and decrease the negative environmental impacts of N loss. The objectives of this research were to i) establish if there are genetic differences in NUE and other related parameters among wheat varieties commonly grown in the Great Plains, ii) determine if there are differences in N response among select varieties with a range of NUEs, and iii) determine if NUE influences N response. This information could be useful in future breeding efforts as researchers seek to develop more efficient varieties. This was approached by conducting two separate studies, a large NUE study with 25 winter wheat varieties, and a smaller N Rate study with 4 varieties that represented a range of NUEs based on the preliminary results of the NUE study. The NUE study was conducted over the course of several seasons and locations, with treatments of consisting of N Rate and variety. The experiment was laid out in a strip-plot design and replicated four times at each location. In the 2010-11 and 2011-12 seasons it was planted at the Kansas River Valley Experiment Field in Rossville, KS. In the 2012-13 season the experiment was planted at two locations, one at Silverlake and another at Ashland Bottoms, KS. The experiment was again planted at two locations in the fall of 2013, in Ashland Bottoms, KS, and Hutchinson, KS. The wheat varieties were grown with two N rates, 0 kg N ha⁻¹ and 90 kg N ha⁻¹. Nitrogen use efficiency was calculated as the grain yield per unit of available nitrogen (sum of soil N and fertilizer N) and ranged from 22-30 kg of grain per kg of N and was strongly influenced by variety with a p<0.001. Several other related parameters, such as grain yield, nitrogen utilization efficiency, harvest index, and fertilizer use efficiency were also significantly affected by variety with a p<0.05. These data suggest there are significant genetic differences in how varieties use and transport nitrogen within their tissues to produce grain. The N Rate experiment was planted in two locations during the 2012-13 season at Silverlake and Ashland Bottoms, KS, and planted again in the fall of 2013 at Ashland Bottoms and Hutchinson, KS. This experiment was laid out in a split-plot design with four varieties and four nitrogen rates. The varieties selected for this study were Duster, Everest, Jagger, and Larned and the four N rates were 0, 33.6, 89.7, and 145.7 kg N ha⁻¹. The results showed significant differences in yield response among the varieties at only one location, Ashland Bottoms (p=0041). Although N response at Silverlake was not significant, mean grain yields between varieties was significant (p<0.001). Two additional parameters, NUE and harvest index (HI), were also significantly different between varieties at Silverlake, KS with a p<0.05, while no additional parameters were significant at Ashland Bottoms. Those varieties that had higher response, Everest and Jagger, also tended to have higher NUEs compared to the other two varieties, Duster and Larned. However, because of the contrasting results between locations, additional research is needed to develop firm conclusions. These results provide significant evidence to support varietal differences in nitrogen use due to genetics, and provide the opportunity for breeders to begin developing varieties with higher NUE and improved N response. However, additional research will be required to determine the specific traits responsible for these varietal differences and to determine the suitability of high NUE crops for meeting the nutritional requirements of the future.
Zhang, Chenxi. "Nitrate Uptake of Kentucky Bluegrass as a Determinant of Nitrogen Use Efficiency." Thesis, North Carolina State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3538535.
Повний текст джерелаNitrate (NO3-) leaching from fertilized land can be detrimental to aquatic ecosystems and human health. Although NO 3- leaching potential is generally found to be low in turfgrass, certain conditions can occur that result in increased leaching loss of nitrogen. Kentucky bluegrass (Poa pratensis L.) is the most widely used cool-season turfgrass species in the temperate and subarctic climate zones in the United States. Due to its popularity, many new cultivars are bred and released each year. Despite the ample amount of information characterizing the agronomic features of Kentucky bluegrass genotypes, little is available documenting their physiological characteristics related to nitrogen use efficiency and how these might affect the NO3 - leaching potential of the genotypes. Such information would be of great value for both scientists and customers.
In this comprehensive study, a screening procedure was developed using nutrient solution culture to evaluate differences in NO3 - uptake among sixty Kentucky bluegrass genotypes. Two cultivars were selected from the sixty to represent genotypes having high vs. low capacity for NO3- uptake. These two cultivars were then used to examine the relationship between NO3- uptake efficiency and competitiveness for soil nitrogen. Finally, these two cultivars were compared to determine if NO3- uptake efficiency affected NO3- leaching potential.
There were significant differences in NO3- uptake at both high (1 mM) and low (0.05 mM) N concentrations among sixty Kentucky bluegrass genotypes, with a strong correlation between uptake rates at high and low N concentrations. Julia and Midnight were selected as representing cultivars with efficient and inefficient nitrate uptake, respectively. In nutrient solution culture, Julia exhibited 56% higher NO3 - uptake rates than Midnight. In a root competition study, in which the root systems of the two cultivars occupied the same soil volume, Julia was more competitive for nitrogen acquisition (absorbed 20 to 71% more NO 3- ) than Midnight. However, the higher NO3 - uptake capacity and better competitiveness for soil N in Julia did not result in lower NO3- leaching potential. These results suggest that differences in root morphology and architecture may play a more important role than uptake capacity in determining nitrate leaching potential among Kentucky bluegrass genotypes.
Munyinda, Kalaluka. "Efficiency of water and nitrogen use by wheat and legumes in Zambia." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75446.
Повний текст джерелаTwo nonnodulating soybean (Glycine max L.) cultivars, Clark RJ1 and N77, or in their absence Pearl millet (Panicum glaucum L.) were judged to be appropriate reference crops for estimating N$ sb2$ fixation by soybeans using $ sp{15}{ rm N}$ isotope dilution techniques. A local soybean cultivar, Magoye, was rated highest among three cultivars tested for its ability to support N$ sb2$ fixation by Bradyrhizobium japonicum and contributed biologically fixed N$ sb2$ to a subsequent wheat crop.
Kindred, Daniel R. "Investigating heterosis for yield, breadmaking quality and nitrogen use efficiency in wheat." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412168.
Повний текст джерелаIrving, Louis John. "Genetic and environmental controls of nitrogen use efficiency in barley ('Hordeum vulgare')." Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415531.
Повний текст джерелаFernando, K. M. C. "Exploration of favourable traits for nitrogen use efficiency in ancient wheat species." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/31015/.
Повний текст джерелаAcharya, Tej Prasad. "Water Requirements, Use Efficiency, and Insect Infestation in Brussels Sprouts, and Nitrogen Use Efficiency in Sweet Basil under Low Tunnels compared to Open-field Production." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/86610.
Повний текст джерелаMaster of Science in Life Sciences
Brussels sprouts and sweet basil are economically important cash crops on the East Coast. Brussels sprouts is a Cole crop and an important source of dietary fiber, vitamins (A, C & K), calcium, iron, manganese and antioxidants. Similarly, sweet basil is a member of the mint family and important high-value herb in the U.S. and the world. It is mainly grown for culinary purposes as a dried and fresh spice in the U.S. However, demand for these commodities is increasing. Low tunnels (LTs) covered with spunbonded fabric can be a practical management tool to increase yield. Results from this study indicate that LTs increase yield of Brussels sprouts and basil, water use efficiency and total nitrogen uptake, while reducing insect pest infestation. Therefore, LTs can be a useful tool to improve sustainability of Brussels sprouts and basil production.
Mahama, George Yakubu. "Variation among grain sorghum genotypes in response to nitrogen fertilizer." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13580.
Повний текст джерелаDepartment of Agronomy
P.V. Vara Prasad
Grain sorghum [Sorghum bicolor (L.) Moench] is an important crop in the semi-arid regions of Africa, Asia and United States. Productivity of grain sorghum is limited by soil fertility, especially nitrogen (N). Sorghum genotypes are known to vary in their response to nitrogen, however, the information on nitrogen use efficiency (NUE) is limited. The objectives of this research were to (a) determine the response of sorghum genotypes (hybrids and inbred lines) to nitrogen fertilizer (b) quantify genotypic differences in NUE; and (c) determine physiological and morphological basis of NUE. Field experiments were conducted at three locations in Kansas (Hays, Ottawa and Manhattan) during 2010 and 2011. Six hybrids and six inbred lines of grain sorghum were grown with 0, 45 and 90 kg N ha-1.The experimental design was a split-plot design with N regimes as main plots and genotypes as sub-plot, with four replications. Planting was done in May and June across all the locations, and nitrogen fertilizer (Urea, 46% N) was applied at emergence. Data on N concentration in the leaves, stems and grain were determined. NUE and components of N use were computed for Ottawa and Manhattan as follows: Nitrogen use efficiency (NUE): Grain weight / N supplied; Nitrogen utilization efficiency: Grain weight / N total in plant; Nitrogen uptake efficiency: N total in plant / N supplied; Percent fertilizer recovery = [uptake (fertilized plot) – N uptake (un- fertilized plot)] / [ N applied ] x 100; and Nitrogen harvest index (NHI) = Grain N / N total in plant. Where N supplied = Rate of N fertilizer applied + soil N supplied. Growth and yield data were collected at all locations. There were significant effects of genotypes (P < 0.05) and nitrogen (P < 0.05) on biomass and grain yield across all locations. Performance of hybrids was generally superior to the inbred lines of all traits. Sorghum hybrids 26506 and 99480 produced maximum grain yield across all locations. While inbred lines B35 and SC35 had the lowest grain yield. Maximum biomass and grain yield was obtained at 90 kg N ha-1, followed 45 kg N ha-1, and lowest in 0 N kg ha-1. There were significant differences among genotypes for all NUE traits at Ottawa and Manhattan. Across genotypes, total NUE ranged from 17.2 to 42.6 kg kg-1, utilization efficiency from 24.3 to 60.2 kg kg-1, N uptake efficiency ranged from 56.1 to 82.5%, recovery from 2 to 52%, and NHI from 43.6 to 81.3%. Among the genotypes, 99480 and 26506 both known to be post–flowering drought tolerance were high in NUE and component of N use. While genotypes B35 and SC35 were the lowest in NUE and components of N use. Overall, our data suggest that there were significant differences for NUE traits in sorghum hybrids and inbred lines. There are opportunities to breed for higher NUE in grain sorghum.
Okeno, James Aketch. "Genetic and physiological studies of yield and nitrogen use efficiency in spring barley /." Göttingen : Cuvillier, 1999. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=008638432&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Повний текст джерелаMiro, Berta. "Identification of traits for nitrogen use efficiency in oilseed rape (Brassica Napus L.)." Thesis, University of Newcastle Upon Tyne, 2010. http://hdl.handle.net/10443/1067.
Повний текст джерелаSilva, Adilson Nunes da. "Nitrogen impacts on maize yield and nutrient use efficiency in contrasting stress environments." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-22042015-153310/.
Повний текст джерелаAdubação nitrogenada (N) e o estresse hídrico tem grande influência no rendimento de grãos de milho, assim, estudos sobre genótipos e o manejo dessa cultura são muito importantes para o aumento da produtividade. Este estudo é apresentado em três capítulos. Os dois primeiros foram desenvolvidos nos Estados Unidos e o terceiro no Brasil. Os objetivos são apresentados na seguinte ordem: (1) o objetivo principal foi entender quais características, se existirem, diferem entre híbridos tolerantes e não-tolerantes à seca, com semelhança em maturidade, que regem a absorção de nutrientes e concentrações destes sob diferentes tratamentos de cultivo e sua influência na produção de grãos. (2) O objetivo principal foi investigar as respostas fisiológicas (fotossíntese (A) e transpiração (E)) e a produção de milho em genótipos, com semelhante maturidade, tolerantes e não tolerantes ao déficit hídrico (P1151 vs. P1162 e P1498 vs. 33D49) em relação a variação de densidade de plantas e doses de N. (3) O principal objetivo foi investigar as respostas de milho à aplicação de nitrogênio em cobertura, ureia fertilizante (15N), em diferentes estádios fenológicos. O objetivo secundário foi: verificar a correlação entre as clorofilas e carotenoides com SPAD (avaliado em V14 e V16) e destas com a biomassa total (BM), índice de colheita (IC), produção de grãos (PG) e do conteúdo de N nos grãos. Como resultados: (1 e 2) Todos os híbridos responderam de forma semelhante para para PG em relação aos tratamentos. O Híbrido P1151 demonstrou semelhantes A e E e menor area foliar do que seu semelhante em maturidade (P1162). Híbrido P1498 pareceu ser capaz de manter a taxa de transpiração foliar e de fotossíntese mais elevadas do que 33D49, durante o período de enchimento de grãos. Este híbrido apresentou uma melhor persistência na captação de água pela raiz no final da estação de cultivo. Geralmente maiores BM e PG na maturidade foram relacionadas a menores intervalos de diferenciação floral e a maior acumulação, na estação seca, de macronutrientes (P e S) no colmo, sendo as ultimas características consideradas como mecanismos de tolerância à seca. (3) A cultura do milho respondeu de forma semelhante em relação a PG à aplicação de N. O teor de nitrogênio nos grãos derivado do 15N fertilizante e a eficiência de uso do fertilizante nitrogenado foram maiores em relação a aplicação de N nos primeiros estádios. Houve correlação positiva e siginificativa para SPAD com a maioria dos pigmentos no estádio de avaliação V16. Provando ser um instrumento eficaz de avaliação indireta de clorofilas e carotenóides em estágios iniciais. A clorofila b, avaliada em V16, apresentou correlação positiva significativa (p<0,05) com teor de N nos grãos, PG, e BM, a clorofila total em V16 também apresentou uma correlação positiva com o teor de N nos grãos, no entanto, as clorofilas a e total, avaliadas em V14, apresentaram correlação negativa com PG. Assim, a medição do teor de pigmentos com o objetivo de estudar as condições nutricionais e previr a produção de grãos deve ser realizada após o estágio V14.
Mundim, Gabriel Borges. "Genetic diversity, path analysis and association mapping for nitrogen use efficiency in popcorn." Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/4780.
Повний текст джерелаConselho Nacional de Desenvolvimento Científico e Tecnológico
Os objetivos deste estudo foram (i) identificar linhagens de milho-pipoca eficientes no uso de nitrogênio; (ii) avaliar a diversidade genética entre linhagens de milhopipoca em alto e baixo N; (iii) investigar os efeitos causais de vários caracteres sobre a eficiência no uso de nitrogênio (NUE) e (iv) identificar marcadores SSR associados com caracteres relacionados à NUE. Foram avaliadas 25 linhagens-elite de milhopipoca pertencentes às populações 'Viçosa' e 'Beija-Flor', em alto e baixo N. Foram mensurados os seguintes caracteres: crescimento diário (DG, cm), massa de parte aérea (SDW, mg), de raiz (RDW, mg), e da planta total seca (TDW, mg), razão parte aérea:raiz seca (RSR), eficiência no uso (NUE, mg mg-¹), na absorção (NUpE, mg mg-¹) e na utilização (NUtE, mg mg-¹) de nitrogênio, diâmetro médio (RAD, mm), comprimento total (TRL, cm), área superficial (RSA, cm²) e volume (RV, cm³) de raízes. Foram identificadas linhagens eficientes em cada nível de N. A avaliação da diversidade genética pelo método de agrupamento UPGMA baseado no quadrado da Distância Euclidiana Média resultou em quatro grupos de linhagens para cada nível de N e a análise de componentes principais mostrou que as linhagens poderiam ser agrupadas predominantemente pelos seus caracteres de parte aérea. A eficiência na absorção de N (NUpE) foi a característica mais importante para a NUE em estádios precoces de desenvolvimento da planta em ambos os níveis de N, por apresentar alta correlação e alto efeito direto sobre a variável principal (NUE) na análise de trilha. Em baixo N, a eficiência na utilização de N (NUtE) também apresentou alta correlação e alto efeito direto sobre a variável NUE, mostrando ser uma característica importante para esta condição nesses estádios. Contudo, a seleção direta ainda parece ser o melhor método para aumentar a eficiência de seleção para NUE em estádios precoces. Três marcadores SSR foram validados como associados com os caracteres relacionados à NUE pela análise de mapeamento associativo baseada em ANOVA.
The objectives of this study were to (i) identify efficient inbred lines in nitrogen use; (ii) assess the genetic diversity among popcorn inbred lines under high and low N; (iii) investigate the causal effects of several traits in nitrogen use efficiency (NUE) and (iv) identify SSR markers associated with the traits related to NUE. Twenty-five elite popcorn inbred lines belonging to the 'Viçosa' and 'Beija-Flor' populations were evaluated under high and low N. The following traits were assessed: daily growth (DG, cm), shoot dry weight (SDW, mg), root dry weight (RDW, mg), total plant dry weight (TDW, mg), root:shoot ratio (RSR), nitrogen use efficiency (NUE, mg mg-¹), nitrogen uptake efficiency (NUpE, mg mg-¹), nitrogen utilization efficiency (NUtE, mg mg-¹), root average diameter (RAD, mm), total root length (TRL, cm), root surface area (RSA, cm²) and root volume (RV, cm³). Efficient inbred lines were identified under each N level. The genetic diversity assessment using the UPGMA method based on the squared Mean Euclidean distance grouped the inbred lines into four clusters for each N level and the principal component analysis revealed that the inbred lines could be categorized predominantly by their shoot traits. Nitrogen uptake efficiency (NUpE) was the most important trait for NUE in the early stages of plant development under both N levels, due its high correlation with and high direct effect on NUE obtained in the path analysis. Under low N, nitrogen utilization efficiency (NUtE) also showed high correlation with and direct effect on NUE, demonstrating its importance in this N level in these early stages. Notwithstanding, the direct selection still seems to be the best method to increase the selection efficiency for NUE in these early stages. Furthermore, three SSR markers were identified as true associations with the traits related to NUE, through the association mapping analysis based on ANOVA.
Bonyadi, Pour Roxanna. "Nitrogen use efficiency in plants : how roots and nodules are balanced in Medicago." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/73274/.
Повний текст джерелаBrasier, Kyle Geoffrey. "Physiological Traits and Quantitative Trait Loci Associated with Nitrogen Use Efficiency in Soft Red Winter Wheat." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/89216.
Повний текст джерелаDoctor of Philosophy
Wheat (Triticum aestivum L.) products account for a significant percentage of the total dietary calories and protein consumed globally. To meet production demands, wheat requires efficient nitrogen (N) management to ensure continued grower profitability and to reduce negative environmental impacts of N lost from agricultural systems. This dissertation sought to evaluate variation among wheat lines for N use efficiency (NUE), assess the performance of wheat lines under multiple N supplies, validate traits that are associated with NUE, investigate the role of photoperiod sensitivity genes on N response, and identify regions of the wheat genome associated with high N use efficiency. These studies were conducted using panels of winter wheat lines grown under two or more N conditions over a combined 32 location-years. Results of Chapter I identified variation in cultivar response to N rates was more frequently observed when a greater number of N rates were used in trials of wheat N response. The first chapter also identified variation among wheat lines for NUE and identified lines that consistently produce high grain yields over N-location-years. In addition, above-ground biomass at physiological maturity was found to be strongly associated with grain yield under all N rates and was highly heritable in both studies. Chapter II utilized a combination of genetic and observable trait data to perform genetic analysis in two bi-parental populations grown in eight Nlocation-years. The study identified reproducible and significant genetic markers associated with NUE for application in wheat breeding programs. Upon analysis of photoperiod sensitive versus insensitive wheat lines in Chapter III, photoperiod sensitive wheat lines had a significant yield advantage under N-limited conditions in Ohio and across N treatments in half of the Virginia testing location-years. This resulted from an increased number of kernels per spike and fertile florets in photoperiod sensitive wheat lines. Results from this dissertation suggest that active breeding and selection for N response may be achieved through the employment of high NUE genes and the continued identification of adapted high NUE wheat parental lines.
Tateno, Ryunosuke. "Nitrogen use efficiency of trees in relation to the relative availability of soil nitrogen to light along forest structure." Kyoto University, 2003. http://hdl.handle.net/2433/148995.
Повний текст джерела0048
新制・課程博士
博士(農学)
甲第10270号
農博第1342号
新制||農||868(附属図書館)
学位論文||H15||N3791(農学部図書室)
UT51-2003-H691
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 武田 博清, 教授 東 順一, 教授 谷 誠
学位規則第4条第1項該当
Theobald, Julian C. "The effect of elevated CO2 on nitrogen allocation between components of the photosynthetic machinery in Spring wheat." Thesis, Open University, 2000. http://oro.open.ac.uk/58084/.
Повний текст джерелаPointeau, Virginie M. "Water-use efficiency and productivity in native Canadian populations of Populus trichocarpa and Populus balsamifera." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/587.
Повний текст джерелаSingh, Ajay. "Water and nitrogen use efficiency of corn (Zea mays L.) under water table management." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116989.
Повний текст джерелаLe drainage et la gestion de la nappe phréatique des parcelles agricoles permet non seulement d'augmenter la production des récoltes, mais aussi de réduire les pertes de nitrates par lessivage, qui contribue à leurs transferts vers les étendues d'eau. Cette étude a examiné l'efficacité d'utilisation de l'eau et de l'azote du maïs grain sous deux conditions de gestion de l'eau et trois niveaux d'application d'azote. Les facteurs climatiques jouent un rôle important dans la production du maïs-grain. Les impacts des changements climatiques sur les projections de maïs-grain et de la production de biomasse en sol drainé ont aussi été évalués pour l'est du Canada pour une période futur de 30 ans (2040 à 2069). L'étude a été accomplie à l'échelle du champ en 2008 et en 2009 à Saint Emmanuel au Québec. Les deux scénarios de gestion de l'eau étaient (a) le drainage conventionnel (FD) et (b) le drainage contrôlé combiné à l'irrigation souterraine (CD-SI). Les trois traitements d'azote (N) (dose faible, moyenne et élevée) ont été appliqués en bande sur trois blocs. L'efficacité d'utilisation de l'eau du maïs (WUE) pour les blocs en FD était de 2.49 kg m-3 et 2.46 kg m-3 en 2008 et 2009 respectivement. Pour ces années, L'WUE du maïs-grain pour les blocs en CD-SI était de 2.43 kg m-3 et de 2.26 kg m-3. Les traitements relatifs à la gestion de l'eau ont permis d'améliorer la production de rendement du maïs-grain significativement (p <0.05) en 2009, que cela soit avec des doses d'azotes basses ou élevées. Cependant, pour des doses intermédiaires, la gestion de l'eau n'a démontré aucun effet significatif (p> 0.05) sur les productions de maïs-grain. Les deux traitements relatifs à la gestion de l'eau n'ont eu aucun effet sur la production de biomasse sèche au-dessus du sol pour les deux années. L'efficacité moyenne de l'utilisation de l'azote (NUE) du maïs grain et de sa biomasse variait de 27 kg kg-1 à 99 kg kg-1. La plus haute NUE (99 kg kg-1) a été observée pour une dose de N faible (~120 kg N ha-1). La plus basse NUE (41 kg kg-1) s'est produite pour une dose de N élevée (~260 kg N ha-1). La consommation des plantes en eau mesurée par la méthode d'écoulement de la sève, vari de 3.55 mm d-1 à 5.11 mm d-1 pour la période de l'apparition des soies jusqu'à la croissance complète du maïs-grain. Ces taux sont en accord avec l'ETc calculée (3.70 mm d-1 à 5.93 mm d-1) pour les deux ans. Bien que, le développement de la soie soit considéré comme le stade critique pour le maïs-grain, la demande en eau fut la plus élevée lors du stade laiteux du développement du maïs (45.63 mm à 59.80 mm). À ce stade, 10 à 12% des besoins totaux de la plante en eau pour la saison furent transpirés. Du stade de la soie jusqu'au développement complet de l'épi de maïs les besoins en eau de la plante ont représenté environ 40 % de son besoin total. Le modèle de récolte STICS (JavaStics v1.0) a été utilisé pour examiner les effets du changement climatique sur la production de maïs- grain, de 2040 à 2069 et sous le scénario d'émissions de gaz à effet de serre B1. Le modèle a d'abord été calibré en utilisant les données mesurées au champ en 2008 et, a ensuite été validé avec l'ensemble des données de 2009. La production de maïs-grain est sous-estimée de 1.5 Mg ha-1 à 2.6 Mg ha-1 pour les deux ans de mesure. La biomasse sèche totale est aussi sous-estimée de 0.9 Mg ha-1 à 2.6 Mg ha-1. Les simulations pour le scénario d'émissions B1 en utilisant des données météorologiques synthétiques font été utilisées dans les mêmes conditions de récolte que 2008. Les prédictions de la production de maïs-grain et de sa biomasse pour la période 2040-2069 sous le scénario d'émissions B1 sont différentes (p <0.05) selon les trois traitements de N. Cependant, l'épreuve de Mann-Kendall n'a montré aucune tendance à la hausse ou à la baisse (MK-stat> - 1.96) pour un niveau de confiance de 95%.
Cormier, Fabien. "Nitrogen use efficiency inwheat in bread wheat (T. aestivum L.) : breeding & gene discovery." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22574/document.
Повний текст джерелаIn a context of fertiliser reduction, breeding for enhanced nitrogen use efficiency in bread wheat is necessary. This PhD thesis resulting from private-public collaboration between the French National Institute for Agricultural Research and Biogemma aimed providing necessary tools. Analyses were conducted using a dataset of 225 commercial varieties genotyped with 24K SNP and tested in eight combinations of year, location, and nitrogen regimes. We showed that even if past selection increased nitrogen use efficiency at high and moderate nitrogen regimes, genetic progresses need to be accelerated and better balanced between traits. This could be achieved by mixing phenotypic and marker assisted selections. In this sense, we developed a method to define quantitative trait locus from genome-wide association study: 333 chromosomal regions involved in 28 NUE-related traits have been identified. The NAM-A1 gene was located in one of these regions and its natural variants were characterized. We also showed that genomic selection could be improved by pre-selecting SNP based on their significance in a multi-environmental genome-wide association study. Networks of epistasis interactions were also studied and an interesting sub-network was identified. Results and methods are discussed regarding breeding and gene discovery strategy. Further investigations and improvements are suggested
Viktor, Aleysia. "Physiological and metabolic factors determining nitrogen use efficiency of tomato seedlings grown with elevated dissolved inorganic carbon and different nitrogen sources." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52999.
Повний текст джерелаENGLISH ABSTRACT: The aim of this study was to determine (l) the influence of elevated dissolved inorganic carbon (DIC) on the nitrogen use efficiencies (NUE) of tomato seedlings grown with different nitrogen sources, (2) how changes in the regulation and activities of nitrate reductase (NR), phosphoenolpyruvate carboxylase (PEPc), carbonic anhydrase (CA) and subsequent changes in metabolites would account for observed changes in NUE, and (3) to what extent elevated DIC contributed to the carbon budget of plants grown with different nitrogen sources. Lycopersicon esculentum cv. Fl44 seedlings were grown in hydroponic culture (pH 5.8) with 2 mM of either N03- or NH4 + and the solutions were aerated with either 0 ppm or 5000 ppm CO2 concentrations. The similar NUEs of NH/-fed plants grown with either root-zone CO2 concentration were largely due to their similar RGRs and N uptake rates. Elevated root-zone DIC had an initial stimulatory effect on N~ + uptake rates, but it seems as if this effect of DIC physiological processes was cancelled out by the toxic effect of unassimilated NH/. The NUE for N03--fed plants supplied with 5000 ppm root-zone CO2 was higher relative to 0 ppm root-zone CO2 and it was possibly due to the higher relative growth rates for similar N uptake rates of 5000 ppm compared to 0 ppm root-zone CO2. Nitrate-fed plants grown with 5000 ppm compared to 0 ppm root-zone CO2 had higher in vivo NR and in vitro NR and PEPc activities. These increases in enzymes activities possibly lead to increases in organic acid synthesis, which could have been used for biomass accumulation. This would account for the increased relative growth rates of N03--fed plants grown with 5000 ppm compared to 0 ppm root-zone CO2. The increasing rootzone CO2 concentrations resulted in the Ó15N values of NH/-plants becoming more positive indicating an absence of enzymatic discrimination. This may have been due to the inhibitory effect of DIC on Nll,+ uptake, causing plants to utilise both internal isotopes equally. The Ól3C studies showed that PEPc contributed equally to both N03-- and NH/-fed plants over the long term. From this it can be concluded that the lower NUE of NH/-compared to N03--fed plants grown with 5000 ppm root-zone C02 was due to increased N uptake and exudation of organic compounds into the nutrient solution. Experiments with 813C also showed that at increasing rootzone CO2 concentrations, PEPc made a bigger contribution to the carbon budget via the anaplerotic reaction.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om (1) die invloed van verhoogde opgeloste anorganiese koolstof dioksied (DIC) op die stikstofverbruiksdoeltreffenheid (NUE) van plante wat op verkillende stikstofbronne gekweek is, te bepaal. (2) Veranderinge in die regulering van nitraat reduktase (NR), fosfo-enolpirovaatkarboksilase (PEPc) en karboonsuuranhidrase (CA) is bestudeer en gekorreleer met waargeneemde verskille in NUE. (3) 'n Beraming van die mate waartoe verhoogde DIC bydra tot die koolstofbegroting van plante, gekweek op verskillende stikstofbronne, word bespreek. Lycopersicon esculentum cv. F144 saailinge is in waterkultuur (pH 5.8) met 2 mM N03- of NH/ gekweek en die oplossings is alternatiewelik met 0 ppm of 5000 ppm CO2 belug. Die NUEs van plante gekweek met NH/ en belug met albei C02 konsentrasies was vergelykbaar grootliks as gevolg van hulooreenkomstige relatiewe groeitempo's en Nopname. DIC het aanvanklik NH/ opname gestimuleer, maar enige latere stimulerende effek van DIC op fisiologiese prosesse was klaarblyklik uitgekanselleer deur N~ + toksiteit veroorsaak deur vertraagde assimilasie. Die NUE van plante gekweek met N03- en 5000 ppm CO2 was hoër as dié van plante gekweek met N03- en 0 ppm CO2. Dit is moontlik gekoppel aan hoër relatiewe groeitempo's teenoor onveranderde N opname tempo's. Plante gekweek met N03- en 5000 ppm CO2 het hoër in vivo NR en in vitro NR en PEPc aktiwiteite getoon as plante gekweek met N03- en 0 ppm CO2. Bogenoemde toenames in ensiem aktiwiteite word verbind met biomassa toename deur verhoogde organiese suur sintese. Dit bied 'n moontlike verklaring vir die hoër relatiewe groeitempo's van plante gekweek met N03- en 5000 ppm CO2 teenoor plante gegroei met N03- en 0 ppm CO2. Die 015N waardes van plante gekweek met NH/ en 5000 ppm CO2 was meer positief as dié van plante gekweek met Nl-l,+ en 0 ppm CO2 wat gedui het op die afwesigheid van ensiematiese diskriminasie. Dit kon as gevolg gewees het van die vertragende effek van DIC op Nl-la + opname wat daartoe sou lei dat die plante beide isotope eweveel inkorporeer. Eksperimente met ol3C het getoon dat PEPc oor 'n lang tydperk eweveel begedra het tot die koolstofbegroting van plante gekweek met beide N03- and N~+. Hiervan kan afgelei word dat die laer NUE van plante gekweek met NH4 + en 5000 ppm C02 in vergelyking met dié van plante gekweek met N03- en 5000 ppm CO2 die gevolg was van verhoogde NH/ opname en uitskeiding van aminosure in die voedingsoplossing. Eksperimente met 0"c het ook getoon dat verhoogde DIe konsentrasies die bydrae van PEPc tot die plant se koolstofbegroting laat toeneem.
Morris, Jerry Whitaker. "Influence of nitrogen fertilization and leaf management on nitrogen use efficiency and agronomic performance of mammoth cultivars of flue-cured tobacco /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08182009-040605/.
Повний текст джерелаMoon, J. W. Jr, D. A. Bailey, E. Fallahi, R. G. Jensen, and G. Zhu. "Effect of Nitrogen Application on Growth and Photosynthetic Nitrogen use Efficiency in Two Ecotypes of Wild Strawberry, Fragaria chiloensis (L.) Duchn." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/215746.
Повний текст джерелаMurray, Cynthia Ruth. "Genotypic differences in nitrogen use efficiency in timothy (Phleum pratense) and tall fescue (Festuca arundinacea)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0016/MQ57316.pdf.
Повний текст джерелаDoerge, Thomas A., and T. Curt Tucker. "The Effect of Nitrification Inhibitors on Nitrogen Use Efficiency in Drip and Furrow Irrigated Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/204469.
Повний текст джерелаHippenstiel, Friederike [Verfasser]. "Energy and nitrogen use efficiency in farm animal nutrition : opportunities and limitations for improvement / Friederike Hippenstiel." Bonn : Universitäts- und Landesbibliothek Bonn, 2013. http://d-nb.info/1043057803/34.
Повний текст джерелаSchuba, Jan [Verfasser]. "Nutritional strategies to optimize efficiency of nitrogen use by lactating dairy cows : kumulative Dissertation / Jan Schuba." Halle, 2018. http://d-nb.info/1160235554/34.
Повний текст джерелаGarabet, Sonia. "Fertilizer use efficiency and nitrogen dynamics in rainfed and irrigated wheat under a Mediterranean-type climate." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262036.
Повний текст джерелаAlpuerto, Jasper Benedict Battad. "Physiological, Metabolic, and Transcriptional Analysis of Submergence Tolerance in Rice and Nitrogen Use Efficiency in Wheat." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/92003.
Повний текст джерелаPHD
Tucker, Andrew Neil. "Managing nitrogen in grain sorghum to maximize N use efficiency and yield while minimizing producer risk." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1424.
Повний текст джерелаGrahmann, Kathrin [Verfasser]. "Nitrogen use efficiency and optimization of nitrogen fertilizer application for stable yields and high quality of cereals grown in conservation agriculture / Kathrin Grahmann." Kassel : Universitätsbibliothek Kassel, 2017. http://d-nb.info/1126457035/34.
Повний текст джерелаMendes, Bastos Leonardo. "N fertilizer source and placement impacts nitrous oxide losses, grain yield and N use efficiency in no-till corn." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18797.
Повний текст джерелаDepartment of Agronomy
Charles W. Rice
Agricultural lands receiving N inputs are considered the primary source of N2O, a potent greenhouse gas. N fertilizer management has shown variable effects on both N2O losses and corn grain yield. The objectives of this study were to assess the impact of N source and placement on N2O emissions, fertilizer-induced emission factor (FIEF), corn grain yield, yield-scaled N2O emissions (YSNE) and N fertilizer recovery efficiency (NFRE). The experiment was conducted from 2013 through 2014 at the Agronomy North Farm located at Kansas State University, Manhattan, KS. The soil was a moderately well-drained Kennebec silt loam. The treatments were broadcast urea (BC-Urea), broadcast urea ammonium nitrate (UAN) (BC-UAN), broadcast coated urea (BC-CU), surface-band UAN (SB-UAN), subsurface-band UAN (SSB-UAN), subsurface-band UAN + nitrification inhibitor (SSB-UAN+I) and a 0 N control. In 2013, SSB- UAN emitted significantly more N2O (2.4 kg N2O-N ha-1), whereas control (0.3 kg ha-1) and BC- UAN (0.6 kg ha-1) emitted the least. In 2014, most treatments emitted between 3.3 and 2.5 kg N2O-N ha-1. Only SSB-UAN+I (1.03 kg ha-1) and control (0.26 kg ha-1) were significantly lower. The use of a nitrification inhibitor decreased N2O emissions by 62% and 55% in 2013 and 2014, respectively. BC treatments had cumulative emissions significantly higher in 2014 compared to 2013. Only SSB-UAN+I had a significantly lower FIEF (0.4%), and 2013 FIEF (0.68%) was significantly lower than that of 2014 (1.38%). In 2013, banded treatments had significantly higher grain yields (from 9.1 to 10.5 Mg ha-1), whereas in 2014 fewer differences among N treatments were observed, ranging from 7.2 to 8.6 Mg ha-1. Banded treatments had significantly lower grain yields in 2014 compared to 2013. Only BC-UAN and SSB-UAN+I had significantly lower YSNE, and 2013 had lower YSNE than 2014. In 2013, SSB-UAN had the greatest NFRE, whereas BC treatments had the lowest. In 2014, N treatments did not differ in NFRE. SSB-UAN and SSB-UAN+I had significantly lower NFRE values in 2014 compared to 2013. Fertilizer source and placement have the potential to mitigate N2O emissions and promote high yields and NFRE in corn, however, the response is dependent on the rainfall pattern after fertilizer application. The option of banding UAN without any additive promoted higher N2O losses on a year when precipitation was well distributed, but also enhanced grain yield and NFRE. On the other hand, under the same precipitation conditions, broadcasting N fertilizer promoted lower N2O losses, grain yield and NFRE, but those were all improved in a wet year. Therefore, the subsurface band placement would be the best option under a normal year, whereas broadcasting fertilizer would be the best option under a wetter year. Further, the use of NI with subsurface band UAN provides the most sustainable option, since the NI decreased N2O losses compared to UAN alone in both years. Further research should evaluate N source and placement combinations under different environments in order to better understand how they impact crop performance and the negative environmental aspects of N fertilization. It is important to test those treatments under different precipitation scenarios and look for trends that indicate the best N management option at the local level.
Weber, Holly S. "Use of nitrogen management products and practices to enhance yield and nitrogen uptake in no-till corn and grain sorghum." Thesis, Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4096.
Повний текст джерелаLeung, Kin-heung Ray, and 梁健鄉. "How to use networking to increase internal efficiency and then increase external effectiveness in an international environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31268110.
Повний текст джерелаLeung, Kin-heung Ray. "How to use networking to increase internal efficiency and then increase external effectiveness in an international environment /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18831266.
Повний текст джерелаSatterfield, Jason Morris. "Evaluation of technology aimed to improve nitrogen use efficiency for delayed-flood rice (Oryza sativa L.) production." Master's thesis, Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-03262009-094038.
Повний текст джерелаRedfern, James. "Performance of cereal aphids in relation to genetic variation and nitrogen use efficiency of wheat (Triticum aestivum)." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/59627/.
Повний текст джерелаOuyang, Duosheng. "New fertilizer combinations for improved nitrogen and phosphorus use efficiency and reduced environmental damage in corn production." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0004/NQ30353.pdf.
Повний текст джерела