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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.
121

Ciclagem de nutrientes, produção de milho em sistema de integração lavoura-pecuária subsequente ao consórcio de pastagens hibernais

Ghizzi, Lucas Ghedin 26 February 2015 (has links)
A integração Lavoura-Pecuária tem foco na busca pela excelência na produção, sendo reconhecida como ferramenta de otimização de recursos naturais e financeiros, conciliando a interação entre as interfaces solo, planta e animal. O objetivo do presente estudo foi avaliar o efeito da inclusão da ervilhaca como pastagem hibernal, sob pastejo com animais recebendo ou não suplementação, na produção da cultura subsequente (produção de milho para silagem e rendimento de grãos) na dinâmica de decomposição e liberação de nutrientes da biomassa residual pós pastejo e das fezes, em um sistema de integração lavoura-pecuária. O trabalho foi desenvolvido na Universidade Tecnológica federal do Paraná - Campus Dois Vizinhos (UTFPR-DV) e os consórcios foram compostos entre as espécies forrageiras: aveia + azevém + suplementação; aveia + azevém + ervilhaca e aveia + azevém + ervilhaca + suplementação, todos com e sem pastejo. A suplementação utilizada foi milho moído em peneira de 1 mm. Utilizou-se como adubação de base na pastagem 200kg de adubo 5-20-10 e 120 kg de N em cobertura distribuídos em 4 aplicações. Posteriormente para a cultura do milho 185 kg de 5-20-10 como adubação de base e 180 kg de N em cobertura distribuídos em 2 aplicações. Avaliou-se a decomposição da MS e liberação de nutrientes (nitrogênio, fósforo e potássio) oriundos da biomassa do consórcio forrageiro e do esterco, componentes de rendimento do milho, rendimento de grão e produção de silagem de planta inteira. Dentre os nutrientes estudados o nitrogênio foi o que teve maior retorno ao sistema após a decomposição da biomassa pastejada, não pastejada e oriundos do esterco bovino. A taxa de decomposição da biomassa sofreu influência do pastejo, apresentando decomposição mais acelerada, enquanto que para a matéria seca fecal, a taxa de decomposição foi maior para o esterco proveniente de animais que receberam suplementação, não observando-se efeito da ervilhaca no retorno de nutrientes ao solo. A presença do animal influenciou somente a variável de massa de mil grãos do milho, a qual demonstrou ser superior em áreas sem pastejo. / The Integrated Crop-Livestock Systems is focuses on the pursuit of excellence in production, being recognized as an tool of optimization natural and financial resources , combining the interaction between interfaces soil , plant and animal. The objective of this study was to evaluate the effect of inclusion of vetch as winterly herbage, with grazing animals receiving or not supplementation, in the production of subsequent crop (maize production for silage and grain yield ) in the dynamics of decomposition and nutrient release post grazing residual biomass and manure, on a crop-livestock system. The work was developed in Federal Technological University of Paraná - Campus Dois Vizinhos ( UTFPR -DV) and the consortium of forage species, were: oat + ryegrass + supplementation; oat + ryegrass + vetch and oat + ryegrass + vetch + supplementation, all with and without grazing. It was used ground maize sieve of 1 mm as supplementation. Were evaluated the decomposition of MS and release of nutrients (nitrogen, phosphorus and potassium) of biomass consortium herbage and manure, corn yield components (number of rows in each ear, number of kernels per row, grains per ear, mass of thousand grain) grain yield (kg ha-1) and production of silage from whole plant. Among the studied nutrients, nitrogen was the more returned to the system after the decomposition of biomass grazed, for not grazed and originating from cattle manure. The biomass decomposition rate was influenced by grazing, with faster decay, whereas for faecal dry matter, the decomposition rate was higher for manure from animals that were supplemented, not observing the effect of vetch return nutrients to the soil. The presence of the animal influenced only mass thousand corn grains, which proved to be superior in ungrazed areas.
122

Métodos indiretos para estimativa de massa de forragem em pastagens de Cynodon spp. / Indirect methods for estimates of herbage mass in Cynodon spp. swards.

Waldeliza Fernandes da Cunha 10 April 2002 (has links)
O planejamento e o manejo do pastejo em sistemas de produção animal em pastagens utiliza como informação essencial valores de massa, produção e taxas de acúmulo de forragem. Esses valores podem ser determinados de maneira rápida e ágil através de uma simples régua graduada em centímetros ou equipamentos mais sofisticados como o prato ascendente, embora resultados experimentais utilizando esses procedimentos sejam bastante escassos para plantas de ambiente tropical. O presente trabalho avaliou esses dois métodos de estimativa de massa de forragem em área de pastagem formada pelos cultivares Florakirk, Tifton 85 e Coastcross de Cynodon spp.. Pastos formados por cada um dos cultivares foram mantidos a 5, 10, 15 e 20 cm de altura através de lotação contínua e taxa de lotação variável, seguindo um delineamento experimental de blocos completos ao acaso com 4 repetições. Durante 12 meses foram geradas curvas de calibração entre altura do pasto, medida por cada um dos dois métodos, e a massa de forragem correspondente. Como resultado foram geradas quatro curvas de calibração do tipo y = a + bx para cada cultivar (y = massa de forragem em Kg MS/ha e x = altura do pasto), uma para cada época do ano (primavera, verão, outono e inverno). De forma geral os valores de intercepto (a) foram os mais influenciados por cultivar e época do ano, com uma variação apenas modesta nos valores de coeficiente angular (b). Essa variação esteve relacionada com modificações da estrutura do dossel dos pastos, particularmente a proporção de material morto. Os métodos não diferiram em precisão, porém o prato ascendente mostrou-se um método mais rápido e ágil. Concluiu-se que apesar das similaridades entre os cultivares estudados, a calibração dos métodos deve ser específica para cada cultivar e realizada frequentemente para que as equações geradas sejam precisas e robustas, de forma a permitir a obtenção de valores confiáveis de estimativas de massa de forragem. / Grazing management and planning of animal production systems from pastures are essentially based on estimates of herbage mass, production and accumulation rates. These values can be rapidly determined with a sward stick and rising plate meter, although experimental results generated this way are scarce for tropical forage plants. The present experiment evaluated both methods for estimating herbage mass in pasture areas formed by Florakirk, Tifton 85 and Coastcross Cynodon spp. cultivars. Paddocks of each of the cultivars were maintained at 5, 10, 15 and 20 cm sward surface height through continuous stocking and variable stocking rate, according to a complete randomised block design with four replications. Over twelve months, calibration equations of stick and plate sward height versus the correspondent herbage mass were generated. As a result, four y = a + bx type calibration equations (y = herbage mass - kg DM/ha and x = sward height) were obtained, one for each season of the year (spring, summer, autumn and winter). Generally, most of the variation among cultivars and seasons occurred in intercept values (a) and less with slope values (b). This variation was related to modifications in sward structure, particularly in dead material content. The methods did not differ in precision, although the rising plate meter proved to be faster and more agile. Despite the similarities among cultivars, calibration of both methods must be specific for each cultivar and carried out regularly in order to result in precise and robust equations capable of generating reliable estimates of herbage mass.
123

Comportamento do sistema radicular do capim Tanzânia (Panicum maximum, Jacq.) sob irrigação e submetido a diferentes intensidades de pastejo. / Root system dynamics of irrigated tanzania grass (Panicum maximum, Jacq.) pasture managed under different grazing intensities.

Daniel Silva Pagotto 22 January 2002 (has links)
O presente estudo foi realizado na Fazenda Areão, unidade da Escola Superior de Agricultura "Luiz de Queiroz", em Piracicaba - SP (22°42'30" Latitude Sul ; 47°38'30" Longitude Oeste) e teve por objetivo avaliar a dinâmica do sistema radicular do capim Tanzânia (Panicum maximum, Jacq.) quando submetido a três intensidades de manejo, correspondidas pelos resíduos pós pastejo de 1000, 2500 e 4000 kg de matéria seca verde por hectare (MSV.ha-1). A área experimental foi irrigada por pivô central, sendo pastejada por novilhos da raça nelore e manejada de forma rotacionada com ciclo de 36 dias, sendo 3 dias de ocupação e 33 dias de descanso. Foram realizadas análises quantitativas da densidade radicular através de sua massa, superfície e comprimento. As análises qualitativas se relacionaram à separação entre as raízes vivas e mortas, de maneira que pudéssemos verificar mais efetivamente o real potencial de absorção para os diferentes tratamentos, assim como o estresse imposto pelo pastejo em cada situação. O desenvolvimento do sistema radicular do capim Tanzânia mostrou comportamento inversamente proporcional às intensidades de pastejo impostas, relacionando pastejos intensos a uma retomada mais lenta na atividade de raízes. Nas condições de irrigação e adubação impostas, o resíduo 1000 kg MSV.ha-1 mostrou menor atividade radicular em relação aos tratamentos de 2500 e 4000 kg MSV.ha-1 de resíduo pós pastejo. Até 12 dias após o pastejo não houve crescimento de novas raízes, indicando que a planta fica sob condição de estresse até pelo menos 2 semanas após ser colhida, independente do manejo imposto. No entanto, para o pastejo mais intenso (resíduo 1000 kg MSV.ha-1), o desenvolvimento radicular ficou comprometido até 21 dias após o pastejo. Para as profundidades analisadas (0-20 e 0-40 cm), na média dos 3 tratamentos, em torno de 76% das raízes vivas e 82% das raízes mortas foram encontradas nos primeiros 20 cm de solo. Estes resultados indicam a possibilidade de novas pesquisas utilizarem apenas esta profundidade para amostragens, uma vez que os valores são relevantes e a dificuldade de coleta em maiores profundidades é fator limitante para trabalhos com raízes. A separação de raízes vivas pareceu ser uma boa metodologia para melhorar a acuracidade na análise dos resultados, já que amostragens do sistema radicular de plantas forrageiras apresentam variabilidade alta. Estudos que relacionem a decomposição e renovação do sistema radicular de forrageiras tropicais com fatores bióticos e abióticos deveriam ser intensificados, buscando melhor entendimento dos fluxos de tecidos da planta inteira em diferentes estações do ano. Metodologias de amostragens associadas a conceitos de interpretação estatística em processos biológicos deveriam ser revistos, uma vez que os estudos existentes sobre sistema radicular de plantas forrageiras tropicais poucas vezes são conclusivos quando interpretados pela estatística ortodoxa. / The present study was carried out at Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba - SP, SP (22°42'30" S; 47°38'30" W) to evaluate the root system dynamics of irrigated Tanzania grass (Panicum maximum cv. Tanzania) pasture managed under three grazing intensities, determinated by adjusting the post grazing residues to 1000, 2500 and 4000 kg of green dry matter per hectare (GDM.ha-1). The experimental area was irrigated by a central pivot system. Nelore steers were used in a 36 days rotational grazing system, represented by an occupation period of 3 days and resting period of 33 days. Quantitative and qualitative evaluations were both performed. In the former case the variables measured were root mass, surface and length. In the latter case, collected samples were separated into live and dead roots, providing a reliable way to assess grazing intensity effects upon root system dynamics. Root system development responded inversely to grazing intensity. Hard grazing (1000 kg GDM.ha-1) was associated to slower root system regrowth compared to moderate (2500 kg GDM.ha-1) and lenient (4000 kg GDM.ha-1) grazing. In the 1000 kg GDM.ha-1 post-grazing residue no root development was observed up to three weeks, whereas for the other two treatments root regrowth was reactivated after 12 days. The three treatments averaged, 76% and 82% of live and dead roots, respectively, were found in the 0-20 cm soil layer. This information might suggest further research on root system dynamics could focus on sampling in the range of 0-20 cm depth. This seems reasonable, since the results obtained in this soil layer were representative and also because root samplings in depth greater than 20 cm (e.g. 20-40 cm) are not so easy to be performed as compared to samplings taken from 0-20 cm. Sample separation into live and dead roots provided a reliable and more accurate method to analyze the data. In part, this can be attributed to lower variability among samples. It is important to stress that additional work has to be undertaken to study decomposition and turnover of the root system of tropical pastures, as well as the relationship between these variables with biotic and abiotic factors. This effort should provide a better understanding on tissue turnover of the plant as a whole (shoots and root system). Finally, improved methods on root samplings should be developed. Also, new concepts on statistical interpretation for biological processes should be emphasized, due to difficulties in interpreting data on root system by conventional statistical methods.
124

The effect of clipping date and height on forage yields, nutritive quality and stored food reserves of a Chilcotin wetland meadow

Heyes, Glenn E. January 1979 (has links)
The objectives of the following research project were to 1) determine the optimum time and intensity of harvesting a wetland meadow in terms of forage yield, forage nutritive quality, and plant vigor; 2) to determine the carrying capacity of a wetland meadow under different seasons of use and; 3) to contribute to the development of a wetland classification scheme by characterizing a wetland meadow. The study site was located on the Fraser Plateau about 100 kms west of Williams Lake, British Columbia, at an elevation of 1250 m. Meadow water table, water pH, water conductivity, water calcium ion concentration, and soil temperatures were measured twice per month. The meadow and surrounding upland soils were classified. The species composition and foliar cover of 5 vegetation zones were described for the meadow and surrounding upland area. To asses meadow productivity and forage nutritive quality under different seasons of use 6 harvesting periods were employed, mid May to mid July, June and July, mid June to mid August, July and August and mid May through August. The standing crop seasonal trend was monitored by analysing forage samples collected twice monthly. Clipping samples were oven dried and weighed to determine harvest yields. The crude protein content of the samples was determined by a microkjeldhal technique. Phosphorus content was assessed by a vanadomolybdate method. Calcium, potassium, magnesium, zinc, copper, iron and manganese contents were determined by spectrophotometry. The relative plant stored food reserves were assessed by an etiolation experiment. Soil - vegetation plugs were collected from all harvest period treatment plots as well as undipped control plots and placed in a dark controlled environment chamber. The etiolated growth was collected, weighed and used to compare the relative plant stored food reserves among different harvest period treatments. A stepwise simple regression procedure was used to compare the seasonal trend data and a stepwise multiple regression procedure was used to compare the different harvest period treatments. A 2 step Student Newman Keuls multiple range test was performed on the etiolation experiment sod reserve indices and harvest treatment total yields data. Meadow water table, water pH, water calcium ion content, water conductivity, soil temperatures at 10 cm and soil temperatures at 50 cm ranged between +29 and -2 cm, 7.0 and 7.4, 14 and 89 ppm, 249 and 840 mmho/cm, 6.9 and 11.2°C and 6.8 and 10.6°C respectively. Meadow soils included a Typic Humisol - Mesic Humisol - Terric Mesic Humisol complex, a calcareous Gleyed Humic Regosol, a calcareous Gleyed Regosol, an Orthic Humic Gleysol and a Gleyed Gray Luvisol. The upland soil was an Orthic Gray Luvisol. The 5 vegetation zones were named according to the dominant plant species. Included were a Carex rostrata zone, a Carex - Betula glandulosa zone, a Carex praegracilis - Juncus balticus zone, a Salix - Betula glandulosa zone, arid a Pinus contorta - Calamagrostis rubescens zone. Productivity and nutritional data collection was restricted to the Carex rostrata zone. The standing crop varied from 1 to 6 mt/ha. The nutrient content of the standing crop varied between 0.35 and 0.51% of tissue, 2.1 - 5.7, 1.0 - 1.5% of tissue, 0.17 - 0.26% of tissue, 133 - 326 ppm, and 49 and 165 ppm for the calcium, calcium - phosphorus ratio, potassium, magnesium, manganese and iron contents respectively. The meadow forage crude protein, phosphorus, zinc and copper contents remained un- changed at 10.1% of tissue, 0.14% of tissue, 30 ppm and 11 ppm through the season. The 8 cm July and August harvest period produced the greatest treatment yield, 6807 kg/ha, followed by the 8 cm - mid June to mid August harvest treatment yield. The least productive treatments were the 8 and 23 cm harvests during the period mid May to mid August. The nutrient content of the meadow forage subjected to the 10 different harvest treatments varied as follows: crude protein - 8.3 to 12.0% of tissue, calcium - 0.368 to 0.646% of tissue, phosphorus - 0.21 to 0.27% of tissue, calcium: phosphorus ratio - 1.4 to 3.6, zinc - 35 to 46 ppm, copper - 13 ppm, potassium - 1.7 to 2.4% of tissue, magnesium-0.19 to 0.23% of tissue, manganese - 194 to 271 ppm and iron - 94 to 119 ppm. Repeated clipping increased the meadow forage crude protein, phosphorus, zinc, copper, potassium, manganese slightly, and iron contents. Repeated clipping reduced the meadow forage calcium: phosphorus ratio. The stored food reserves of the meadow vegetation was found not to vary with harvest treatment. Based on productivity, nutritive quality and plant vigot data, grazing during the period mid June to mid August and close utilization (an 8 cm as opposed to a 23 cm stubble height) appears most appropriate. Wet meadow hay should be cut as early as possible. The theoretical safe maximum carrying capacity is 23 AUM'S/ha (20 AUM'S/ ha when grazed to an 8 cm stubble height during the period mid June to mid August). The meadow characterization and productivity data will be useful to person(s) undertaking the task of formulating a classification scheme for British Columbia wetland meadows. / Land and Food Systems, Faculty of / Graduate
125

Ácido Salicílico na Germinação de Brachiaria humidicola / Salicylic acid and Brachiaria humidicola germination

Zanet, Cauê 10 November 2011 (has links)
Made available in DSpace on 2016-01-26T18:56:23Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 502487 bytes, checksum: bfc738d62eed60fc6f911a343aa6b5e6 (MD5) Previous issue date: 2011-11-10 / The aim of this work was to evaluate germination, seedling dry matterand germination speed index of Brachiaria humidicola treated with different doses of salicylic acid in two separate experiments. The experiment I consisted of five doses of salicylic acid 0.0, 69.05, 138.1, 207.15, 276.15 mg L-1 diluted in water. Seeds were immersed in solution with salicylic acid for one hour and dried out at room temperature for 24 hours. Seeds were not subjected to any sort of stress. In experiment II were used the best responses in experiment I (69.05, 138.1 mg L-1) and untreated seeds (dried) and soaked in water and then subjected to water stress. Seeds were assessed for for germination at different water potentials (0, -0.3, -0.6, -0.9 MPa) induced by mannitol. Salicylic acid did not improve seed performance when subjected to water stress and even water available. Dry seeds presented better results than any treatment tested. / O objetivo deste trabalho foi avaliar a germinação, a matéria seca de plântulas, e o índice de velocidade de germinação de sementes de Brachiaria humidicola tratadas com diferentes doses de ácido salicílico em dois experimentos distintos. O experimento I compreendeu cinco doses de ácido salicílico 0,0; 69,05, 138,1; 207,15; 276,15 mg L-1 do ácido diluído em água. As sementes foram submersas em solução com ácido salicílico por uma hora, e secas em temperatura ambiente por 24 horas. As sementes não foram submetidas a nenhum tipo de estresse. No experimento II foram utilizadas as melhores respostas obtidas no experimento I (69,05, 138,1 mg L-1 ) e sementes sem tratamento (secas) e embebidas em água, sendo então submetidas a estresse hídrico. As sementes foram avaliadas quanto ao teste de germinação em diferentes potenciais hídricos (0; -0,3; -0,6; -0,9 MPa), induzidos por manitol. O ácido salicílico não melhorou o desempenho das sementes quando submetidas ao estresse hídrico e mesmo com água disponível. Sementes secas apresentaram melhores resultados que qualquer tratamento testado.
126

Ácido Salicílico na Germinação de Brachiaria humidicola / Salicylic acid and Brachiaria humidicola germination

Zanet, Cauê 10 November 2011 (has links)
Made available in DSpace on 2016-07-18T17:51:07Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 502487 bytes, checksum: bfc738d62eed60fc6f911a343aa6b5e6 (MD5) Previous issue date: 2011-11-10 / The aim of this work was to evaluate germination, seedling dry matterand germination speed index of Brachiaria humidicola treated with different doses of salicylic acid in two separate experiments. The experiment I consisted of five doses of salicylic acid 0.0, 69.05, 138.1, 207.15, 276.15 mg L-1 diluted in water. Seeds were immersed in solution with salicylic acid for one hour and dried out at room temperature for 24 hours. Seeds were not subjected to any sort of stress. In experiment II were used the best responses in experiment I (69.05, 138.1 mg L-1) and untreated seeds (dried) and soaked in water and then subjected to water stress. Seeds were assessed for for germination at different water potentials (0, -0.3, -0.6, -0.9 MPa) induced by mannitol. Salicylic acid did not improve seed performance when subjected to water stress and even water available. Dry seeds presented better results than any treatment tested. / O objetivo deste trabalho foi avaliar a germinação, a matéria seca de plântulas, e o índice de velocidade de germinação de sementes de Brachiaria humidicola tratadas com diferentes doses de ácido salicílico em dois experimentos distintos. O experimento I compreendeu cinco doses de ácido salicílico 0,0; 69,05, 138,1; 207,15; 276,15 mg L-1 do ácido diluído em água. As sementes foram submersas em solução com ácido salicílico por uma hora, e secas em temperatura ambiente por 24 horas. As sementes não foram submetidas a nenhum tipo de estresse. No experimento II foram utilizadas as melhores respostas obtidas no experimento I (69,05, 138,1 mg L-1 ) e sementes sem tratamento (secas) e embebidas em água, sendo então submetidas a estresse hídrico. As sementes foram avaliadas quanto ao teste de germinação em diferentes potenciais hídricos (0; -0,3; -0,6; -0,9 MPa), induzidos por manitol. O ácido salicílico não melhorou o desempenho das sementes quando submetidas ao estresse hídrico e mesmo com água disponível. Sementes secas apresentaram melhores resultados que qualquer tratamento testado.
127

Leaf structure in southern African species of Salsola L. (Chenopodiaceae)

Klopper, Ronell Renett 26 May 2006 (has links)
Salsola L. is one of the largest genera within the Chenopodiaceae. It has been suggested that almost 90 species occur in southern Africa where the plants are most conspicuous in karroid areas. Members of Salsola are of considerable importance as pasture plants in the Karoo, especially during winter and periods of prolonged drought. Some species also have medicinal and other valuable properties. However, not all Salsola species are beneficial; some may cause diseases and deficiencies in livestock, leading to high mortalities and severe financial loss. Because of the occurrence of harmful and beneficial species within the same area, correct identification of the different species is of extreme importance. Correct identification is, however, rendered problematic by the great morphological similarity of almost all southern African Salsola species and uncertainties concerning the infrageneric classification of the group. There is a great need for a system of easy identification that can be used in the herbarium as well as in the field. This is especially so since available keys to the group cannot be used to identify sterile specimens. There also exists great uncertainty as to the exact identity of most of the 69 new species described by V.P. Botschantzev (Komarov Botanical Institute, St Petersburg) between 1972 and 1983. For this reason many of the names have hardly been taken up and used by South African botanists. A clear delimitation of the different character states within the genus would greatly facilitate and enhance the process of solving the systematic problems that exist within the genus. A comparative anatomical study of the leaves of southern African Salsola species was conducted using LM and SEM techniques. Leaf anatomy proved to be very useful for delimiting groups within the genus. Of particular importance is the structure of the leaf in transverse section and the type of the indumentum. The investigated species can be primarily divided into two main leaf types, according to the presence or absence of a uniseriate hypodermis underlying the adaxial epidermis. A secondary division can be made by indumentum types. Four main indumentum types have been identified based on the appearance of the abaxial leaf surface. One of these indumentum types can be further subdivided according to the area of the leaf covered by trichomes and the number of elongated cells in the trichomes. There is a weak association between leaf type and subsection, as well as between leaf type and indumentum type. No obvious association could be found between leaf or indumentum type and fruit type or any other macromorphological character. Further investigation in this respect is required. In general the species possessing an adaxial hypodermis tend to have a denser covering of trichomes than those species lacking one. This denser indumentum probably provides the plants with better insulation to help prevent excessive water loss and to protect subtending tissues from extreme heat in their arid environment. When studied in combination with other anatomical and ecological evidence these characteristics might prove to be very useful to help establish a classification system whereby Salsola species can be more easily identified. / Dissertation (MSc (Botany))--University of Pretoria, 2000. / Plant Science / unrestricted
128

The Effect of Early Spring Clipping and the Level of Nitrogen Fertilizer on the Yield of Improved Pastures, North Logan, Utah

Sumrit, Dechar 01 May 1971 (has links)
The influence of agronomic practices on forage production and chemical composition of grass-legume pasture mixture was studied at the Utah State University Dairy Farm, North Logan, Utah, during spring and summer, 1970. The soil is a well-drained Millville silt loam that has about a 1 percent slope . It is high in potash, phosphorus, and lime, having a pH of 7.9. Analysis of the clipping management showed that the early spring clipping decreased the yield of forage. The losses in total yield due to spring clipping were approximately four to five times the yields received in early spring clipping. The grasses were affected more than the legumes. The yields of dry forage increased with the increase in fertilizer rates from 0 through 300 pounds of nitrogen per acre. There was no advantage to splitting the nitrogen fertilizer of 300 pounds per acre into three applications. Most of the effects of spring clipp1ng and nitrogen fertilization were re fleeted in the first summer harvest. The plots fertilized with nitrogen produced a higher yield and nitrate content than the check plots. Legumes were higher in nitrate on the unfertilized plots than the grasses, but lower on the fertilized plots.
129

Plant and Animal Performance in Tall Fescue and Tall Fescue/Legume Pastures

Bingham, Troy J. 01 May 2014 (has links)
Tall fescue is the one of most common grasses in irrigated pastures throughout the Intermountain West. Two limitations of tall fescue are a decrease in productivity during hot summer months and the need for supplemental nitrogen (N). The objective of this research was to compare tall fescue-alfalfa (TF+ALF), tall fescue-birdsfoot trefoil (TF+BFT), tall fescue-nitrogen fertilizer (TF+N), and tall fescue without nitrogen fertilizer (TF-N) on forage yield, nutritional quality, and livestock performance. Research plots were established at the Utah State University Pasture Research Facility in Lewiston, UT in 2010 and grazed in 2012 and 2013. Treatments were arranged in a randomized complete block design with four replications and divided into four paddocks per replication. Three Angus crossbred steers with an average starting weight of 380 kg were placed on each treatment and rotated to a new paddock every 7 days. A put-and-take method was used throughout the growing season such that each paddock received 80% utilization. Four forage samples were collected from each paddock just prior to grazing using a 0.5 m2 quadrat for determination of dry matter (DM) and nutrient content. ADF, NDF, IVTD, and TDN were used to estimate nutrient content and steers were weighed every 28 days to determine livestock performance. Forage yield was highest (P<0.05) in TF+N (5164 kg ha-1), followed by the TF+BFT (4721 kg ha-1) and TF+ALF (4463 kg ha-1) treatments, whereas, the TF-N treatment had the lowest yield (2920 kg ha-1). In this study, TF+BFT (593 g kg-1) and TF+ALF (593 g kg-1) had a better (P≤ 0.05) season-long average TDN value than TF+N (558 g kg-1), which in turn was higher (P≤ 0.05) than TF-N (550 g kg-1). Steer average daily gains (ADG) were different (P<0.05) in every treatment with TF+BFT (0.73 kg d-1) being the highest, followed by TF+ALF (0.67 kg d-1), then TF+N (0.61 kg d-1), and similar to forage yield, TF-N had the lowest ADG (0.40 kg d-1). Tall fescue greatly benefits from added N whether via fertilizer or N transfer by legumes and this study showed that BFT and ALF mixed with TF increases plant and animal performance while reducing fertilizer costs and helps maintain a more environmentally sustainable pasture.
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Hay and pasture production in Virginia: organized subject matter, factual data, job analyses, and related information on the important jobs in the hay and pasture enterprise in Virginia for the use of teachers and students of Vocational Agriculture

Thomas, Allen King January 1947 (has links)
M.S.

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