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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.
231

Monitoring der Resistenzentwicklung des Maiszünsler (Ostrinia nubilalis), Hübner) gegenüber Bt-Mais / Monitoring of European corn borer (Ostrinia nubilalis>, Hübner) resistance to Bt-corn

Meise, Thomas 06 November 2003 (has links)
No description available.
232

Sicherheitsforschung und Monitoringmethoden zum Anbau von Bt-Mais: Expression, Nachweis und Wirkung von rekombinantem Cry1Ab in heterologen Expressionssystemen / Biosafety research and monitoring methods of Bt-corn: Expression, detection and effect of recombinant Cry1Ab in heterologous expression systems

Nguyen, Thu Hang 08 November 2004 (has links)
No description available.
233

Agroclimatic response mapping for sugarcane production in southern Africa.

Hull, Phillip John. January 2008 (has links)
As is the case in many other regions in the world, sugarcane production in southern Africa is affected by a wide range of climatic conditions, which can vary considerably from location to location and from year to year. As a result, the season length and growth cycles of sugarcane in southern Africa differ greatly. Such conditions include the hot and dry regions of northern KwaZulu-Natal, Swaziland and Mpumalanga, where sugarcane is mostly irrigated, to the humid sub-tropical coastal belt extending from the far north coast of KwaZulu-Natal to areas in the Eastern Cape, as well as the cool frost prone midlands regions of KwaZulu-Natal. Owing to the wide range of climatic conditions in which sugarcane is grown in southern Africa, there are many different external factors that affect sugarcane production, including a range of pests and diseases, frost occurrences and variations in soil water. The objective of this research was to (1) identify a number of important variables that affect cane production in southern Africa, (2) employ suitable models to reflect these variables, and (3) simulate and map the extent and severity of these variables at a high spatial resolution over southern Africa. Such variables include the Eldana saccharina and Chilo sacchariphagus stalk borers, sugarcane rust fungus, heat units with selected base temperatures, frost, soil water content, soil compaction, irrigation water demand, conducive and non-conducive growing conditions, flowering proficiencies for sugarcane, sugarcane yields and yield increments per unit of irrigation. The distribution patterns of the above-mentioned variables relied greatly upon the various models employed to represent them, as well as the accuracy of the temperature and rainfall databases to which the various models were applied. Although not definitive, the models used to reflect the variables which had been identified were considered to be generally satisfactory. The resolution at which the variables which had been identified in this study were mapped, was also found to be adequate. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
234

Development of fungal biological control of four agriculturally important pests, Sitophilus oryzae, Trialeurodes vaporariorum, Planococcus ficus and Eldana saccharina, in South Africa.

Chambers, Craig Brian. January 2005 (has links)
The use of entomopathogenic fungi to control agriculturally important pests, both in greenhouses and in the field, has been demonstrated by various authors for a number of years. This has been brought about by the development of resistance in certain pest species to chemical applications and a growing public awareness of the safety implications of residual insecticides. Several entomopathogenic fungi were tested against four insect pests found in the Republic of South Africa (RSA), the greenhouse whitefly, Trialeurodes vaporariorum, the rice weevil, Sitophilus oryzae, the grapevine mealybug, Planococcusficus and the sugarcane stem borer, Eldana saccharina. Further concentration, temperature and humidity studies were conducted with selected isolates on the rice weevil, S. oryzae. Sitophilus oryzae is considered one ofthe most important pests of stored grain. Several fungal isolates were tested against the rice weevil, four of which, B1, PPRI 6690, PPRI 6864 and PPRI 7067, were selected for further testing based on the mortality results over a 21 d period. Varying conidial concentrations were applied and at high doses of 1x10 -6 conidia ml -1 with mortality rates of to 84% achieved. LT 50 values ranged from 6 - 68d. Increased spore concentration resulted in an increase in overall mortality. Temperature and humidity was found to affect the infection potential of the four isolates tested. Four temperatures ranging from 15 - 30°C were tested. The highest mortality rates were obtained at 25°C where mortality ranged from 46 - 65% in 14d. Mortality rates decreased with decreasing temperature, and no mortality was recorded at 30°C. Temperature was found to significantly alter the LT 50 values, increasing the LT 50 with decreasing temperatures. Decreasing the humidity resulted in an increased LT 50 and a reduction in the overall mortality rates. The mortality of S. oryzae ranged according to the RH and isolate. Isolates Bland PPRI 6690 resulted in the highest mortalities of 80 and 83% at 92.5% RH, with LT 50's of 6.3d and 6.4d, respectively. Several entomopathogenic fungi were tested against T vaporariorum, P. ficus and E. saccharina, three key pests of South African crops. Nine fungal isolates were tested against the greenhouse whitefly, T vaporariorum, with mortalities ranging from 26.7 - 74.7% over 14d. Beauveria bassiana Isolates Bl and PPRl 6690 produced the highest mortality rates and were recommended for further pathogenicity testing against T. vaporariorum. Planococcus ficus is a common pest ofvineyards in the Western Cape Province, South Africa. Nine entomopathogenic fungi were screened against P.ficus, only two of which produced mortality. Eldana saccharina is a stalk borer, which infests sugarcane in large areas of Southern Africa. Five isolates were tested against second and third instar larvae, three of which, B1, PPRl 6864 and PPRl 6690 resulted in mortalities. Mean percentage mortality was low for all three isolates. From the study it was evident that two of the isolates tested, Bland PPRI 6690 (B. bassiana), showed potential against three of the four pests, and two isolates of Lecanicillium lecanii caused mortality in P. ficus. Further research and understanding of the effect of environmental conditions, spore concentration and epizootic potential would result in the further development of these isolates as future biological control agents. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
235

Avaliação dos fatores de risco no processamento de café verde para o aparecimento de ocratoxina A (OTA) / Evaluation of risk factors in green coffee processing for ochratoxin A (OTA)

Márcia Dimov Nogueira 03 April 2007 (has links)
Dentre os perigos relacionados com a produção de café verde, a ocratoxina A (OTA) é considerada significativa nesse produto. Com o objetivo de estudar a origem da OTA no processamento de café verde e avaliar os possíveis fatores de risco (região, etapas do processamento, fungos, insetos e ácaros) que poderiam contribuir na presença de OTA, foram amostradas três fazendas nos seguintes municípios: Bom Jardim (RJ), Espírito Santo do Pinhal (SP) e Cornélio Procópio (PR), onde havia a produção de café verde pela via seca e úmida. Foram coletadas 109 amostras de grãos de café, em diversas etapas do processamento, no período de maio a agosto de 2002. As amostras foram colhidas de acordo com fluxograma estabelecido e as etapas estudadas foram: cereja (campo), via seca, via úmida, armazém e café de varrição. Dessas amostras, 10 apresentaram OTA, que variou na sua quantificação de 3 a 101 ng.g-1. A maior prevalência de OTA foi a do café de varrição 57%, a via úmida apresentou uma prevalência de 10,3% e a via seca 7%. Na etapa cereja o fungo potencialmente toxigênico mais encontrado foi Penicillium spp, e quanto aos insetos, as larvas de Diptera e os Homoptera; na via úmida foram encontradas linhagens do Aspergillus seção Nigri e Circundatti e Penicillium spp, a infestação predominante foi a broca do café e os ácaros da família Acaridae; na etapa via seca registrou-se o isolamento de fungos do gênero Penicillium spp e Aspergillus seção Nigri , a broca do café foi a infestação predominante junto com os ácaros da família Acaridae, na etapa de armazém foram isolados Penicillium spp e Aspergillus seção Nigri, o inseto predominante foi a broca do café e os ácaros da família Acaridae; no café de varrição foram isolados Penicillium spp e Aspergillus seção Nigri e a broca do café estava presente junto com insetos da Ordem Diptera. Os resultados de cada etapa foram comparados por Análise de Variância em um nível de significância de 95%. Na análise de fatores de risco o café de varrição foi o mais significativo (p< 0,001). / The ochratoxin A (OTA) is considered to be among the most significant coffee contaminants with related hazards. With the purpose to study the origin of the OTA in the processing of green coffee and to evaluate the possible risk factors (region, step of processing, fungi, insects and mites) that could contribute in the OTA presence, had been selected three regions (states) of Brazil: Bom Jardim/RJ, Espírito Santo do Pinhal/SP and Cornélio Procópio/PR. A total of 109 samples of coffee beans were collected in conformity with flow chart established at different stages of ripening and processing: cherry (field), dry method, wet method, and warehouse and varrição coffee, from May to August of 2002. Of these samples 10 had presented OTA, which varied in its quantification from 3 to 101 ng.g-1. The biggest prevalence of OTA was the varrição coffee 57%, the wet method presented a prevalence of 10,3% and dry way 7%. In the stage cherry fungi potentially toxigenic was more found Penicillium spp, the insects had been the larvae of Diptera and the Homoptera; in the wet way it was found Aspergillus section Nigri and Circundatti and Penicillium spp, the predominant infestation was the coffee berry borer and the mite of the Acaridae family; in the stage wet methods spp was registered the isolation the Penicillium spp and Aspergillus section Nigri, the predominant infestation was the coffee berry borer together with the mites of the Acaridae family; in the stage of warehouse had been isolated Penicillium spp and Aspergillus section Nigri, and the predominant insect was the coffee berry borer and mites of the family Acaridae; in the varrição coffee had been isolated Penicillium spp and Aspergillus section Nigri the coffee berry borer was the most present insects together of Diptera. The results of each step had been with compared by Analysis of Variance. In the analysis of risk factors the varrição coffee\" was the factor most strongly related to the risk of the presence of OTA (p<0,001 ).
236

Návrh rekonstrukce dřevěných konstrukcí stávajícího objektu / The reconstruction design of timber structures of the existing building

Bartlová, Jana January 2015 (has links)
The content of this work was to carry out construction-technical survey of timber structures of the existing building in order to design an appropriate procedure for their reconstruction. The survey showed construction in an unsatisfactory to disrepair, so further work also includes the static calculation of new structures proposed instead of the current. Timber structure in the building has form of staircase, roof and ceiling construction. Newly designed the following types of stairs and roof trusses from which the lower belts are used as ceiling beams. The new proposal also includes possible roofing, roofing options, developed one of them. The work also includes drawings, bill of materials and cost estimate staircase structure and truss. Specialization in the field of civil engineering is represented by drawings of the new truss and passport (view of current state) whole object on parcel ST.74 / 1, land Tišnov (okr.Brno-venkov), the content of which was the basis for this work.
237

Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield

Maas, Bea 20 November 2013 (has links)
No description available.

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