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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Urea Formulations on the Productivity of Bermudagrass and Bermudagrass-White Clover Pastures

Timberlake, Caitlin 01 January 2015 (has links)
Bermudagrass (Cynodon dactylon L.) is a perennial warm-season grass that is very responsive to nitrogen (N) fertilization. Excessive N applications have negative environmental consequences and make maintaining mixed swards difficult. This study determined the effects of enhanced efficiency (EE) N fertilizers and fertilizer rate on bermudagrass yields, nutritive values, and white clover persistence. Nitrogen sources included urea, urea formulated with Agrotain® (U+A), urea with Agrotain® and dicyandiamide (SuperU), a polymer-coated urea (ESN), ESN+urea (75% ESN, 25% urea), and methylene urea (MU). In the urea formulation trial, SuperU and U+A maximized forage yields at lower N rates. The dicyandiamide in SuperU did not increase yields over U+A. Highest production efficiency was achieved at lower N rates. ESN had the lowest relative stimulate growth, which may increase clover persistence. In the clover persistence trial, the addition of N fertilizer began decreasing clover populations after 112 kg N/ha. Slow-release fertilizers (ESN, ESN+urea, MU) had higher clover percentage at the final harvest. Crude protein and in vitro digestible dry matter increased, while neutral detergent fiber and acid detergent fiber decreased with the addition of white clover. SuperU and U+A were more efficient and ESN had lower relative stimulated growth beneficial for mixed pastures.
32

TEMPERATURE EFFECTS ON GERMINATION CHARACTERISTICS AND TRAFFIC TOLERANCE OF NEWLY ESTABLISHED STANDS OF NINETEEN COMMERCIALLY AVAILABLE CULTIVARS OF SEEDED BERMUDAGRASS

Deaton, Michael Todd 01 January 2012 (has links)
Nineteen bermudagrass (Cynodon dactylon (L.) Pers.) cultivars were evaluated for field emergence, establishment rate, traffic tolerance, post-harvest seed coating, germination velocity, and total germination under varying temperature regimes. Two cultivars were evaluated for thermal modeling, day/night temperature fluctuations, day lengths, and effects of fluridone on speed and percentage of total germination. The effect of cultivar was highly significant for visible field germination, time to 100% cover, and traffic tolerance in both 2010 and 2011. Riviera was the slowest or equivalent to the slowest for visible germination. Casino Royale was the fastest or equivalent to the fastest for visible germination. Yukon was the slowest to reach 100% cover in both years, while Sovereign was the quickest for 2010. Riviera and Sovereign were equivalent for the quickest to cover in 2011. Riviera and Yukon ranked highest and lowest, respectfully, in tolerance to simulated athletic traffic. There were no significant effects (p>0.05) of post-harvest seed coatings. There were highly significant differences among cultivars in germination velocity and total germination when grown under 20-year average day/night temperatures representing data from Lexington, KY on 15 May to 1 August in 15 day intervals. Evaluations for day/night temperature regimes, day length regimes, and effects of fluridone on the germination speed and percentage were also completed on Riviera and Casino Royale. Day/night regimes of 35/20, 35/25, and 40/25 degrees Celsius were evaluated. Significant differences (p<0.05) were observed, 35/20oC producing the fastest and highest percentage of germination across both cultivars. Day length was evaluated for 8, 12, 14, and 16 hours with no significant differences (p<0.05) observed. Fluridone significantly (p<0.05) decreased the germination time and increased the percentage of total germination of Riviera while only significant differences (p<0.05) in germination time observed with Casino Royale.
33

Performance Test - 1988 National Turfgrass Evaluation Program Bermudagrass Trials

Kopec, D. M., Mancino, C. F. January 1989 (has links)
Bermudagrass germplasm was evaluated for turfgrass color, quality, chlorosis symptoms, leaf texture and percent plot ground cover, in order to assess turf adaptation under desert conditions. Both experimental materials and commercially available germplasm were different for these traits during 1988, which was the second year's evaluation of a 5-year-long national trial for turf-type bermudagrass.
34

Efeitos da irrigação com esgoto tratado e fertilização nitrogenada na ciclagem de carbono e nitrogênio e no metabolismo microbiano de um solo cultivado com capim-Bermuda Tifton 85 / Effects of irrigation with secondary treated sewage effluent and nitrogen fertilization on carbon and nitrogen cycling and on microbial metabolism on a Tifton 85 bermudagrass pasture

Nogueira, Sandra Furlan 19 June 2008 (has links)
Em muitas partes do mundo o aumento na demanda de água tem estimulado pesquisas relacionadas às práticas de reuso sustentáveis. Dentre as atividades humanas, a irrigação agrícola se revela como uma das práticas de maior consumo de recursos hídricos naturais. Uma alternativa para minimizar este problema é o reuso de efluentes gerados por sistemas biológicos de tratamento de esgotos. O objetivo desta pesquisa foi avaliar os efeitos da irrigação com esgoto tratado na dinâmica do carbono (C) e nitrogênio (N) e na atividade microbiana de um solo sob pastagem. O estudo foi conduzido em uma pastagem de capim-Bermuda Tifton 85 (Lins-SP), onde o delineamento experimental foi o de blocos completos com seis tratamentos: SI (sem irrigação e sem fertilização), A100 (água potável + 520 kg de N ha-1 ano-1); E0, E33, E66 e E100 (irrigação com esgoto tratado + 0, 33, 66 e 100% de 520 kg de N ha-1 ano-1). Os tratamentos receberam entre 420 a 1500 mm de esgoto tratado e água por ano, correspondendo a uma entrada pelo esgoto tratado de 640 a 2300 kg ha-1 ano-1 de C e de 135 a 480 kg ha-1 ano-1 de N. Utilizando como referência os estoques de C e N de SI, o menor decréscimo de C ocorreu em E33 (1,2 Mg ha-1) e o maior em A100 (7,9 Mg ha-1). Alterações no estoque de N do solo ocorreram após quatro anos de irrigação, onde A100 apresentou decréscimo de cerca de 450 kg de N ha-1. Os estoques de N dos tratamentos irrigados com esgoto tratado não foram afetados. A entrada de C e N orgânicos pelo esgoto tratado não afetaram a composição isotópica do C (\'delta\' 13C) e do N (\'delta\' 15N) da fração estável da matéria orgânica do solo (MOS) do solo. A alteração de \'delta\' 13C nos solos dos tratamentos irrigados (-0,7 a -1,2%o ), em relação a SI, foi resultante da mineralização do carbono orgânico remanescente do solo (plantas C3). Os valores de \'delta\' 15N do N da MOS (0 a 5 cm) foram significativamente maiores (+2,2%o) nos tratamentos irrigados com esgoto tratado do que em SI e A100, refletindo diferenciadas taxas e processos de ciclagem de N. A abundância natural de 15N nas folhas do capim-Bermuda refletiu a composição isotópica do N do solo, com enriquecimento de +2,5%o e +4,9%o em relação a A100 e SI, respectivamente. As taxas líquidas de mineralização e nitrificação negativas ou nulas nas épocas Seca-04, Chuvas-05 e Seca-05 indicaram predominância de processos de imobilização do N pela microbiota em virtude uma alta relação C:N da MOS. Nas épocas de Chuvas-06 e Seca-06 as taxas tornaramse positivas indicando a diminuição da relação C:N da MOS, término do efeito priming e, portanto, ciclagem interna de N. Os solos dos tratamentos apresentaram baixo consumo (-0,1kg de C ha-1 sem-1) ou pequena emissão média de CH4 (+0,8 kg de C ha-1 sem-1). A disponibilidade de N e a umidade do solo não representaram fatores limitantes nos tratamentos, assim as emissões de CO2 não diferiram entre si na maior parte das datas de coleta (médias de 14,7 e 12,2 Mg de C ha-1 para épocas de chuvas e seca, respectivamente). Os maiores fluxos de CO2 relacionaram-se com os períodos de maior precipitação e/ou irrigação do que com os tratamentos. Os maiores fluxos de N2O foram observados após a aplicação de N mineral nos tratamentos irrigados com esgoto tratado, sendo proporcionais as maiores quantidades de N adicionado. As relações médias entre o C da biomassa microbiana e o C orgânico total (Cmic:COT) dos tratamentos variaram de 2,3 a 3,8% ao longo das épocas, indicando boa resiliência do agroecossistema, onde os microrganismos apresentaram variações temporárias de biomassa. Interferências positivas do manejo (corte do capim e fertilização com N mineral) resultando em aumento de Cmic foram observadas no 1º ano hidrológico e Seca-06, como resultado da maior umidade do solo e com isso condições mais favoráveis para a disponibilização de C. Na Seca-04, com o aumento da atividade metabólica, e Chuvas-05, sem alteração deste parâmetro, ao longo do manejo, o quociente metabólico (qCO2) apresentou um cenário de eficiente conversão de C-CO2 em biomassa microbiana. No 2º ano hidrológico, com a diminuição das lâminas de irrigação os tratamentos irrigados e fertilizados apresentaram decréscimo de Cmic e respiração mantida (Seca-05) ou aumentada (Chuvas-06) após o manejo, os valores de qCO2 indicaram condições desfavoráveis a microbiota. Com a pouca interferência dos tratamentos, os indicadores eco-fisiológicos não foram suficientemente sensíveis para mostrar o manejo com menor impacto na qualidade do solo, revelando apenas cenários do metabolismo microbiano ao longo das práticas agrícolas. A quantidade de C exportada por E33, como biomassa (15,2 Mg de C ha-1 ano-1) não diferiu das maiores produções, a alteração em seu estoque de C foi inferior aos demais tratamentos irrigados, sugerindo ser o manejo mais sustentável, em termos de C, utilizando esgoto tratado como irrigação. Os tratamentos E100 (Seca-04) e E66 (Chuvas-05) representaram os manejos com as maiores exportações de N, respondendo linearmente até 940 ha-1 de N ano-1. De acordo com as variáveis avaliadas, o manejo com maior sustentabilidade produtiva e ambiental foi o tratamento E100, situação onde as saídas de N não superaram as entradas / In many parts of the world, the increasing demand and, especially in arid regions the natural scarcity of water has stimulated researches in terms of sustainable water reuse practices. Within human activities, common agricultural irrigation reveals one of the most consumptive practices of natural water resources. One alternative to minimize this problem represents the reuse of effluent generated by biological sewage treatment systems. The objective of this study was to investigate the impact of treated wastewater application in the dynamic of carbon (C) and nitrogen (N), and microbial metabolism of a soil under pasture. The study was carried out at Lins, São Paulo State, Brazil on a Tifton 85 bermudagrass pasture irrigated with secondary treated sewage effluent using a randomized complete block design with six treatments: SI (control, without irrigation and fertilization), W100 (potable water irrigation + 520 kg of N ha-1 year-1); E0, E33, E66 and E100 (treated wastewater irrigation + 0, 33, 66 and 100% of 520 kg of N ha-1 year-1). Samples of treated effluent/water, soil, plant (litter fall), and gases were taken from January 2004 through October 2007 and the treatments were kept under irrigation management receiving between 420 and 1,500 mm of water and treated sewage corresponding to an input of 640 to 2,300 kg ha-1 yr-1 of C and 135 to 480 kg ha-1 year-1 of N . Soil C stocks decreased slightly in the E33 treatment (-1.3 Mg ha-1) and a larger decrease was observed in W100 (-7.9 Mg ha-1). The inputs of organic C by the treated sewage did not affect the soil carbon isotopic composition (\'delta\' 13C), and in the irrigated treatments measured shifts in the isotopic signature (-0,7 a -1,2%o ) were caused by the mineralization of the remaining soil organic matter (SOC) (C3 plants). After 4 years of irrigation the only significant changes in soil N stocks were found in the W100 treatment (-450 kg de N ha-1). The \'deta\' 15N signature of the soil organic matter (0-5 cm depth) in the treatments irrigated with treated sewage was significantly higher (+2,2%o) than WI and W100, this suggests higher nitrogen cycling. The \'delta\' 15N signature of grass was enriched relative to the soil of W100 and WI +2,5%o and +4,9%o respectively). Negative or null rates of mineralization and nitrification occurred in the dry season of 2004, rainy and dry season of 2005 indicated an immobilization by the microorganisms, as a result of a high C:N ratio in the SOC. In the dry and wet seasons of 2006, mineralization and nitrification rates became positive suggesting a decrease of the C:N ratio, and the end of both priming effect and, thus the beginning of N cycling in the soil organic matter. Soils in the treatments showed low CH4 consumption rates (-0.1 kg de C ha-1 semester-1) and in some cases low emissions (+0.8 kg de C ha-1 emester-1). Nitrogen availability and soil moisture did not appear to be limiting factors for the treatments, thus CO2 emissions did not differ from each other over the collections (averages of 14.7 e 12.2 Mg of C ha-1 for wet and dry season, respectively). The highest CO2 fluxes were more related to periods of high precipitation and/or irrigation than to the applied treatments. The highest emissions of nitrous oxide were observed after the application of mineral N to the treatments irrigated with treated sewage, and the emissions were straightly related to the N addition. Values of Cmic:TOC (microbial C : Total Organic C) in the treatments averaged between 2.3 and 3.8 % through the seasons which means a significant resilience of the ecosystem, indicating that soil microbial community varied seasonally in their Cmic. Addition of mineral nitrogen and grass cutting practices influenced positively resulting in increase of Cmic in the first hydrological year and in the dry season in 2006, as well as an increase of soil moisture resulting in good conditions for C availability. With the increase metabolic activity in the dry season of 2004 and a continuous metabolic activity in the rainy season in 2005, the metabolic quotient (qCO2) resulted in an efficient scenario of conversion of C-CO2 into microbial biomass. In the second year, with a decrease of the irrigation depths and an increase in salts concentration after fertilization, the treatments irrigated with treated sewage and fertilizers presented decrease of Cmic with stable respiration (dry season 2005) or increase respiration (wet season 2006) after the management, and as a result qCO2 indicated inappropriate conditions for the microorganisms. In the dry season (2006) the physiological profile of the soil remained instable with no stress and Cmic increased and soil respiration remained inaltered. According to these results, the microbial indicators were not efficiently sensitive for revealing the more impacting management to the soil. The co-physiological indicators showed only the regular microbial metabolism along the agricultural practices. Carbon biomass exported by the grass in the E33 (15.2 Mg C ha-1 yr-1) did not differ from the biomass produced in the other treatments and the alterations in its C stocks were low compared to the other treatments. As a result, E33 seems to be the more sustainable and efficient practice for treated sewage use. Both the E66 and E100 treatments had high measured rates of N export, responding linearly up to 940 kg of N ha-1 yr-1. Thus, according to the variables studied, the management with highest sustainability was E100 where N outputs did not surpass the inputs
35

ENHANCED EFFICIENCY NITROGEN FORMULATION EFFECT ON GRASS-LEGUME PASTURE PRODUCTIVITY

Payne, Kathryn Marie 01 January 2019 (has links)
The use of nitrogen (N) fertilizer is generally restricted on mixed species forage systems due to its stimulatory effect on grasses which increases competition with legume species. Reduced legume growth from this competition can compromise forage nutritive value and prospective yields. The controlled-release nature of several enhanced efficiency fertilizer N products holds the potential to improve legume persistence in mixed species pastures while providing supplemental N required by the grass component. The studies contained in this dissertation evaluated the effect of different enhanced efficiency N formulations (ATU, ESN, methylene urea, SuperU, and a 75% ESN: 25% urea blend) and untreated urea on yield, nutritive value, and legume persistence in a ‘Wrangler’ bermudagrass and ‘Durana’ white clover mixture (2014-2016 growing seasons), ‘KY-31’tall fescue and ‘Kenland’ red clover mixture (2015-2016 growing seasons), and ‘KY-31’ stockpiled tall fescue (2015-2017). The three studies were conducted at the University of Kentucky Spindletop Research Farm in Lexington, KY in a randomized complete block design. In the bermudagrass-white clover study, all enhanced efficiency N sources maintained white clover populations similar to the unfertilized grass/clover control, but only ESN caused greater clover composition than standard urea. Total forage yields increased linearly with N rate in all years, but dry weather conditions in the second and third years resulted in lower total yield. Forage nutritive value followed general trends throughout each growing season, but ESN’s ability to maintain clover resulted in higher nutritive value. In the tall fescue-red clover, total forage yields curvilinearly increased with N rate in 2015 but did not vary in 2016. ESN and ESN+urea blend treatments retained clover composition similar to that of the unfertilized control. Stockpiled forage yield increased with higher N rates. Enhanced efficiency N fertilizers with the ability to control N release can enhance forage yield while maintaining clover in mixed species swards.
36

Investigating Cold Hardiness and Management Practices of Warm-season Putting Green Species in the Transition Zone

Kauffman, John M 01 August 2010 (has links)
Warm-season turf species are becoming increasingly popular for putting green use in the transition zone. Ultradwarf bermudagrass (Cynodon dactylon (L.)  C. transvaalensis Burtt-Davy) is the prevalent warm-season putting green species, but seashore paspalum (Paspalum vaginatum Swartz) and ‘Diamond’ zoysiagrass [Zoysia matrella (L.) Merr.] may also be grown in the transition zone. Warm-season species are susceptible to winter injury and may require different management regimes than cool-season species. Therefore, the objectives of this research were to assess the impacts of various management practices on warm-season putting green species and characterize the physiological basis for differences in freeze tolerance of various warm-season putting green species. Field studies determined sampling procedures form thatch-mat depth and soil organic matter content of warm-season putting greens and assessed the impact of various management practices on different warm-season putting green species/varieties. The relative freeze tolerance of ‘Champion’ and ‘TifEagle’ ultradwarf bermudagrass cultivars, ‘SeaDwarf’ seashore paspalum, and Diamond zoysiagrass were determined, along with the accumulation of proline and polyamines during cold acclimation, in growth chamber studies. All species/varieties required different sampling numbers for determination of thatch-mat depth and soil organic matter. More sand was incorporated into the turf canopy and surface hardness was increased with brushing and vibratory rolling TifEagle putting greens after sand topdressing application than either treatment alone. Putting green management programs with lower mowing heights and increased mowing frequencies increased ball roll distance on a MiniVerde putting green without negatively affecting turf quality. Weekly vertical mowing + daily grooming on TifEagle reduced thatch depth and turfgrass quality, while increasing topdressing incorporation over either treatment alone. Diamond was the most freeze tolerant species/variety, followed by TifEagle, Champion, then SeaDwarf. Cold acclimation increased proline concentration for all species/varieties except SeaDwarf, but had inconsistent effects on polyamines. Spermidine and putrescine concentrations differed with species/variety, but were not correlated to freeze tolerance.
37

Mowing Turfgrasses in the Desert

Kopec, David, Umeda, Kai 09 1900 (has links)
2 pp. / Describes how to select the appropriate lawn mower to properly mow the species of grass at the correct height for high, medium, or low maintenance levels.
38

WEAR TOLERANCE OF SEEDED AND VEGETATIVELY PROPAGATED BERMUDA GRASSES UNDER SIMULATED ATHLETIC TRAFFIC

Bayrer, Theresa A. 01 January 2006 (has links)
The use of seed-propagated bermudagrasses [Cynodon dactylon (L.) Pers.], particularly for athletic fields, is rapidly increasing. Recently developed seeded cultivars have been bred for improved turfgrass quality (finer texture, darker green color, etc.) and for increased cold tolerance, but their ability to tolerate wear has not been investigated. This study was conducted to determine if three seeded cultivars could tolerate simulated athletic wear as well as one vegetative cultivar commonly used in Kentucky. The seeded cultivars, Riviera, Princess 77 and Yukon were planted at 24.4 and 48.8 kg PLS ha-1 and the vegetative cultivar Quickstand was sprigged at 1250 and 2500 bu ha-1 in the second week of June. Beginning at the end of August each year (in conjunction with the Kentucky high school football season), simulated wear treatments equivalent to either three, two, one or zero football games wk-1, using a Brinkman traffic simulator, were imposed. Plots were then evaluated for turfgrass quality (TQ) and percent turfgrass cover (PC) through mid-November. The possibility that precipitation amounts and timing may have been a factor is the large end of season PC means is also examined. Final PC means for each season under the highest wear treatment were mixed with Princess 77 having a statistically greater mean (Pandlt;0.0001) of 42% than any other cultivar in 2002, where the 2003 results showed Riviera to have the statistically higher (Pandlt;0.0001) mean (71%) over the other cultivars. TQ ratings were inconsistent when used as a measure of wear tolerance. Stolon fresh weights were also measured between the cultivars as an examination of morphological characteristics that could be associated with wear tolerance, but were not statistically correlated (Pandgt;0.05) to a given cultivars wear tolerance ability.
39

TRINEXAPAC-ETHYL AND OVERSEEDING EFFECTS ON SHEAR STRENGTH AND TOLERANCE TO SIMULATED TRAFFIC OF FOUR BERMUDAGRASS CULTIVARS GROWN ON A SAND-BASED SYSTEM

Deaton, Michael Todd 01 January 2009 (has links)
Bermudagrass (Cynodon dactylon L.) is often used for athletic fields due to its wear tolerance and recuperative ability. Studies were conducted May 2007 through November 2008 in Lexington, Kentucky. The cultivars ‘Quickstand’, ‘Tifway’, ‘Riviera’, and ‘Yukon’ grown in a sand-based medium were used to investigate differences in wear tolerance and shear strength. Trinexapac-ethyl (TE) was applied at label rates and frequencies or untreated. Overseeding treatments were perennial ryegrass (Lolium perenne L.) at 0, 612, and 1225 kg PLS ha-1. Traffic treatments were applied with a Brinkman traffic simulator 3 d wk-1 August through October. Shear tests were conducted using the Clegg shear tester once wk-1 for the same period. The main effect of cultivar was significant (p Quickstand=Yukon) and overseeding at the medium and high rates. Significant differences (p Tifway =Yukon (2007) and with Riviera ≥ Quickstand > Tifway = Yukon (2008). Significant differences (p0.05) in either year for traffic tolerance or shear strength.
40

Desenvolvimento da grama Tifton 419 submetida a distintos manejos de adubação e irrigação / Development of the bermuda grass Tifton 419 submitted to different fertilization and irrigation managements

Silva, Tatiane Bortoletto Gomes da [UNESP] 18 February 2016 (has links)
Submitted by TATIANE BORTOLETTO GOMES DA SILVA null (tatibortoletto@live.com) on 2016-04-20T11:15:44Z No. of bitstreams: 1 Dissertação_Tatiane_final.pdf: 2327927 bytes, checksum: 4763720bd11ec4d660134d198140b887 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-26T13:36:02Z (GMT) No. of bitstreams: 1 silva_tbg_me_bot.pdf: 2327927 bytes, checksum: 4763720bd11ec4d660134d198140b887 (MD5) / Made available in DSpace on 2016-04-26T13:36:02Z (GMT). No. of bitstreams: 1 silva_tbg_me_bot.pdf: 2327927 bytes, checksum: 4763720bd11ec4d660134d198140b887 (MD5) Previous issue date: 2016-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Um gramado esportivo deve apresentar boa condição de jogo além de bom aspecto visual. O nutriente requerido em maior quantidade em gramados é o nitrogênio, portanto deve-se ter o conhecimento do manejo criterioso de sua aplicação, com a quantidade adequada e os melhores momentos para a adubação. Outro nutriente importante no manejo de gramados é o potássio que confere resistência ao estresse hídrico. O manejo adequado da irrigação mantém a umidade do solo, evitando que o gramado sofra com a deficiência hídrica e perca qualidade. Objetivou-se com esse trabalho obter recomendações técnicas para os manejos nutricional e hídrico da grama bermuda Tifton 419 (C. dactylon x C. transvaalensis) utilizada nos gramados esportivos brasileiros, de forma a melhorar sua qualidade. O trabalho foi realizado no Departamento de Solos e Recursos Ambientais da Faculdade de Ciências Agronômicas de Botucatu – Unesp (Universidade Estadual Paulista “Júlio de Mesquita Filho”). O gramado foi estudado nos períodos do outono e do inverno, com início em abril de 2015 e finalização em setembro de 2015. Estudou-se as seguintes características: concentração dos nutrientes no solo, massa de matéria seca das aparas, concentração de nutrientes na lâmina foliar das aparas, quantidade de nutrientes nas aparas, intensidade de cor verde, altura do gramado, tração do gramado e taxa de cobertura verde do gramado. O delineamento experimental adotado foi em blocos casualizados composto por quatro repetições em esquema fatorial triplo, com quatro doses de nitrogênio, duas doses de potássio e duas frequências de irrigação. As doses de nitrogênio e potássio variaram de acordo com a estação do ano, no outono aplicou-se 28,1 kg N ha-1; 84,4 kg N ha-1; 140,6 kg N ha-1; 196,8 kg N ha-1; 28,1 kg K2O ha-1; 84,4 kg K2O ha-1 e no inverno aplicou-se 16,9 kg N ha-1; 50,6 kg N ha-1; 84,4 kg N ha-1; 118,1 kg N ha-1; 16,9 kg K2O ha-1; 50,6 kg K2O ha-1 (parceladas em três vezes). As frequências de irrigação foram: diária e a cada dois dias. A dose de nitrogênio de 562,5 kg ha-1ano-1 estimulou suficientemente o crescimento da parte aérea, porém, em detrimento do desenvolvimento das raízes e estolões. A dose de potássio de 112,5 kg ha-1ano-1 foi suficiente para o gramado e para não exaurir a quantidade de potássio no solo. As duas frequências de irrigação foram satisfatórias para manter o gramado verde. / A sport turfgrass must provide good visual appearance as well as good playing conditions. Nitrogen is the nutrient required in largest amounts on turfgrass and the adequate nitrogen fertilization may provide a good quality of sports field. Other important nutrient is the potassium that confer resistance to stress. The irrigation management keeps soil moisture avoiding that the turfgrass suffer with water stress and quality lost. The objective of this work was to determine technical recommendations for nutritional and irrigation managements of bermudagrass Tifton 419 (C. dactylon x C. transvaalensis), used in Brazilian sports field in order to improve their quality. The research was conducted in Department of Soil and Environmental Resources of the Faculdade de Ciências Agronômicas de Botucatu – Unesp (Universidade Estadual Paulista “Júlio de Mesquita Filho”). The turfgrass was studied during autumn and winter, beginning in April 2015 and finishing in September 2015. The following characteristics were studied: concentration of nutrients in the clipping, dry mass of clipping, the amount of nutrients in the clipping, dry mass of root and stolon, the turfgrass green color intensity, height of the turfgrass, rotational resistance and green cover rate. The experiment was set in randomized blocks design, with four replications, involving four nitrogen rates, two potassium rates and two irrigation frequency. The rates of nitrogen and potassium varied according to the season, in the autumn were applied 28,1 kg N ha-1; 84,4 kg N ha-1; 140,6 kg N ha-1; 196,8 kg N ha-1; 28,1 kg K2O ha-1; 84,4 kg K2O ha-1 and in the winter were applied 16,9 kg N ha-1; 50,6 kg N ha-1; 84,4 kg N ha-1; 118,1 kg N ha-1; 16,9 kg K2O ha-1; 50,6 kg K2O ha-1 (parcel three times). The frequency of irrigation was daily or each two days. Nitrogen rate of 562,5 kg ha-1year-1 stimulated growth of shoots over the stolon and root. Potassium rates didn’t show significantly different for any treatment evaluated, therefore the rate of 112,5 kg ha-1year-1 was sufficient. Both irrigation frequencies were satisfactory to maintain the turfgrass green.

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