Thesis (M.S.)--East Tennessee State University, 2003. / Abstract. Includes bibliographical references (leaves 109-116). Also available full text as a .pdf file via the Internet. Requires Adobe Acrobat Reader software.

Thesis (M.S. in environmental science)--Washington State University, May 2007. / Includes bibliographical references (p. 30-33).

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Orientador: Flávio Dutra de Resende / Banca: Flavio Augusto Portela Santos / Banca: Marco Antonio Alvares Balsalobre / Banca: Ricardo Andrade Reis / Banca: Roberta Carrilho Canesin / Resumo: O experimento foi desenvolvido na APTA, Colina - SP, com objetivo de estudar o desempenho de tourinhos da raça Nelore durante a recria em pastagens e terminação em confinamento. Foram utilizados 84 animais com peso inicial de 205 kg e 8 meses de idade. Durante a seca os animais foram mantidos em pastagens de Brachiaria brizantha cv. Marandu, sob lotação contínua, submetidos a dois suplementos (proteico ou proteico e energético). No verão os animais foram submetidos a dois suplementos (mineral ou proteico). No outono os animais foram submetidos a três suplementos (mineral, proteico ou proteico e energético). No verão e outono foram utilizados módulos de pastagens de Panicum maximum cv. Tanzânia, sob lotação intermitente. Cada subgrupo, totalizando doze tratamentos, foi confinado com dieta única na terminação sendo abatidos com 500 kg. Na recria as características das forragens foram mantidas semelhantes, sendo as diferenças atribuídas ao tipo de suplementação. Durante a seca o suplemento proteico e energético resultou em maior ganho em peso (0,501 kg/dia) comparado com proteico (0,368 kg/dia). Animais que receberam suplemento proteico no verão apresentaram maior peso no inicio do outono (343 kg) comparado com suplemento mineral (326 kg). O peso inicial no confinamento foi influenciado pelas estratégias de suplementação na recria sendo maior nos animais que consumiram suplemento proteico e energético no outono (404 kg) seguidos por suplemento proteico (393 kg) e suplemento mineral (370 kg), o que refletiu no tempo de confinamento, sem alterar desempenho (0,910 kg/dia) e mantendo semelhantes as características de carcaça / Abstract: The experiment was conducted at APTA, Colina - SP, to study the performance of Nellore bulls rearing stages on pasture and feedlot finishing. 84 Nellore cattle, with initial body weight of 205 kg and 8 months old were used. In dry season the animals were kept on Brachiaria brizantha cv. Marandu in continue stoking and submitted to two supplements (protein or protein and energy). In the second phase (summer) the animals were submitted to two supplements (mineral or protein). In the third phase (fall) the animals were submitted to three supplements (mineral, protein or protein and energy). In phases II and III modules pastures of Panicum maximum cv. Tanzania in discontinue stoking were used. Each subgroup, totalizing twelve treatments, was later confined to single diet for finishing with 500 kg. During the growing stages the characteristics of pasture, were kept similar, being the differences attributed to the type of supplementation. During the dry season the animals that consumed energy and protein supplement showed greater weight gain (0,501 kg/day) compared to protein (0,368 kg/day). The protein supplementation in the summer increased body weight (343 kg) compared to mineral (326 kg). The initial body weight in confinement was influenced by the rearing strategies, when animals fed with protein and energetic supplement in the fall season presented higher weight (404 kg) then the animals fed with protein supplement (393 kg) and mineral (370 kg). This caused difference in confinement time but not in the weight gain (0,910 kg/day) and carcass characteristics / Doutor

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A drenagem à uma etapa importante na construÃÃo de um gramado esportivo, auxiliando no desenvolvimento da grama e na utilizaÃÃo por parte dos usuÃrios. Para um projeto de drenagem, informaÃÃes sobre a sensibilidade da cultura ao estresse por excesso de Ãgua facilitarÃo nas tomadas de decisÃes quanto ao dimensionamento do projeto. Partindo da premissa de que o excesso de Ãgua prejudica o crescimento e desenvolvimento da cultura da grama e que os Ãndices Sum excess water (SEW30) e Index day stress (IDS) sÃo sensÃveis Ãs variÃveis de desenvolvimento da cultura, objetivou-se com este estudo identificar a sensibilidade da cultura da grama bermuda ao excesso de Ãgua com base na anÃlise de variÃveis de desenvolvimento da cultura. O experimento foi conduzido com a grama bermuda (Cynodon spp.), durante trÃs meses, em um modelo fÃsico localizado no LaboratÃrio de HidrÃulica e IrrigaÃÃo do Departamento de Engenharia AgrÃcola da Universidade Federal do Cearà (UFC). No local foram construÃdos tanques de alvenaria que medem 1,5 m de altura, 2,0 m de largura e 1,5 m de comprimento, que permitem controlar o nÃvel do lenÃol freÃtico em diferentes posiÃÃes. Foi utilizado substrato à base de areia, conforme especificaÃÃes da United States Golf Association (USGA). O delineamento experimental utilizado foi inteiramente casualizado com cinco tratamentos e quatro repetiÃÃes. Os tratamentos consistiram em elevaÃÃes do lenÃol freÃtico, variando as profundidades entre 0,05 m e 0,20 m, realizadas quinzenalmente, com duraÃÃo de trÃs dias, alÃm do tratamento sem elevaÃÃo do lenÃol freÃtico. As variÃveis utilizadas para testar os tratamentos foram: comprimento de raiz, taxa de fotossÃntese, massa da matÃria seca de raÃzes, estolÃes, rizomas, colmos e folhas e massa seca das aparas de grama. Na anÃlise de variÃncia os tratamentos foram comparados pelo teste F, considerando-se um nÃvel mÃnimo de significÃncia de 5% de probabilidade. Os resultados permitem concluir que os valores associados Ãs variÃveis analisadas demonstram decrÃscimos em seus rendimentos com o incremento no nÃvel de estresse por excesso de Ãgua; a cultura da grama bermuda mostra-se mais sensÃvel ao excesso de Ãgua no primeiro estÃdio de desenvolvimento e a taxa fotossintÃtica no tratamento com maior nÃvel de estresse, ou seja; lenÃol freÃtico a 0,05m da superfÃcie do solo decresceu em torno de 2/3 do valor para a condiÃÃo de ausÃncia do lenÃol freÃtico. / The drainage is an important stage in building a filed sports turf helping in the development of grass and in use by the users. For a drainage project information on the sensitivity of culture to stress by excess water will facilitate making decisions as to the design of the project. Assuming that the excess water affect the growth and development of the culture of grass and that the indices SEW30 and IDS are sensitive to the variables of development of the cultivation, the objective of this study was to identify the sensitivity of the culture of Bermuda grass to the excess of water based on the analysis of variables for crop development and stress treatments by excess water as referenced in the indices SEW30 and IDS. The experiment was conducted for three months with the Bermuda grass (Cynodon spp.) in the area of the Laboratory of hydraulic and irrigation of the Department of Agricultural Engineering of Federal University of Cearà (UFC). On the site were constructed tanks of masonry which measure 1.5 m in height, 2.0 m wide and 1.5 m in length, which allows you to control the level in the groundwater in different positions. The soil mix used the base of sand as per specifications of the United States Golf Association (USGA). The experimental design was completely randomized with five treatments and four replications. The treatments consisted of six elevations in the groundwater, varying the depths between 0.05 m and 0.20 m, and carried out monthly, with a duration of three days and the treatment without elevation of the groundwater. The variables used to test the treatment was root length, photosynthesis rate, dry weight of roots, rhizomes, stolons, culms and leaves and dry weight of clippings grass. In the variance analysis the treatments was compared by F test, considering a minimum level of significance was 5% probability. It was concluded that the values assigned to the variables analyzed showed decreases in their income with the increase in the stress level by excess water; The culture of bermudagrass was more sensitive to excess water in the first stage of development; and the photosynthetic rate at higher stress levels, decreases reaches approximately 2/3 of the value for the condition of no groundwater.

No information is available on the role of allelopathy in crop rotation systems of the Western Cape Province of South Africa, where more than 100 000 ha are under threat from herbicide-resistant rye grass. A study which investigated the use of allelopathic properties for the suppression of rye grass hybrid type (Lolium multiflorum x perenne) was undertaken. These objectives were accomplished by: a) exploring the use of allelopathic properties of crop residues for rye grass suppression; b) evaluation of the role of allelopathy from seeds, seedlings, roots and above-ground plant material of rotational crops; c) assessing the distribution of genetic and morphological variability of rye grass and d) determining the interactions among micro-organisms and allelopathic root leachates from rotational crops and rye grass. In the field trials, growth inhibitory or stimulatory effects were observed on crops exposed to the residues of others. Medic suppressed the weed type rye grass. The radicle length of rye grass was inhibited by seed leachates from wheat and lupine. Growth inhibition from lupine seed and seedling leachates was evident in rye grass radicle length and cumulative germination percentage. Morphologically, 50% of the total number of specimens was classified as rigid rye grass, 48% as the hybrid, namely L. multiflorum x perenne and 2% as perennial rye grass. The wide genetic and morphological variation detected in rye grass may be due to high genotypic plasticity and hybridisation for producing the weed type L. multiflorum x perenne. The faster growth rate of rye grass on Langgewens soil treated with barley root leachates was revealed by Principal Component Analysis (PCA) as a probable association with growth-promoting soil micro-organisms. Crop cultivars and weeds may modify the soil micro-organism populations to their advantage and to the disadvantage of other species by the release of root exudates that apparently differ in composition between plant species. The effect on microbial communities varied with source of exudates and between soils. / Thesis (PhD)--University of Pretoria, 2011. / Plant Production and Soil Science / unrestricted

The red imported fire ant (Solenopsis invicta)(RIFA) is a major pest in the United States, causing serious economic and human costs. This study explored the feasibility of using digital aerial remote sensing in multispectral/multitemporal detection and mapping of RIFA mounds. Comparison of photointerpretive mound counts versus ground control counts was performed within two grass types, common Bermuda and tall fescue. Flights collecting digital image data occurred at three intervals in 2009, with ground truth data collected collaterally. Poisson regression count modeling was first utilized for analysis of both datasets. Moran's Index geospatial analysis was applied following the Poisson model. Outcomes in this study from these models demonstrate their ability to robustly support studies for tracking and control of RIFA or other pest populations. Additionally, in one location, type of grass cover appeared to affect detectability of mounds between the two methods.