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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.
1

Markergestützte Vererbungsanalyse der Pollenfertilitätsrestauration bei Winterroggen (Secale cereale L.)

Wolf, Markus, January 2001 (has links)
Hohenheim, Univ., Diss., 2001.
2

Chromosomale Lokalisation von Restorergenen argentinischer und iranischer Herkunft in F2-Populationen von Winterroggen /

Dreyer, Felix. January 2000 (has links)
Hohenheim, Universität, Thesis (doctoral), 1999.
3

Microsymbiont diversity and phylogeny of native bradyrhizobia associated with soybean (Glycine max L. Merr.) nodulation in South African soils

Naamala, J, Jaiswal, SK, Dakora, FD 01 June 2016 (has links)
Abstract The genetic diversity and identification of slow- and fast- growing soybean root nodule bacterial isolates from different agro-climatic regions in Mpumalanga, Limpopo and Gauteng Provinces of South Africa were evaluated. The 16S-rDNA-RFLP analysis of 100 rhizobial isolates and eight reference type strains placed the isolates into six major clusters, and revealed their site-dependent genomic diversity. Sequence analysis of single and concatenated housekeeping genes (atpD, glnII and gyrB), as well as the symbiotic gene nifH captured a considerably higher level of genetic diversity and indicated the dominance of Bradyrhizobium diazoefficiens and Bradyrhizobium japonicum in Mpumalanga, Limpopo and Gauteng Provinces. Gene sequence similarities of isolates with type strains of Bradyrhizobium ranged from 97.3 to 100% for the 16S rDNA, and 83.4 to 100% for the housekeeping genes. The glnII gene phylogeny showed discordance with the other genes, suggesting lateral gene transfer or recombination events. Concatenated gene sequence analysis showed that most of the isolates did not align with known type strains and might represent new species from South Africa. This underscores the high genetic variability associated with soybean Bradyrhizobium in South African soils, and the presence of an important reservoir of novel soybean-nodulating bradyrhizobia in the country. In this study, the grouping of isolates was influenced by site origin, with Group I isolates originating from Limpopo Province and Group II and III from Mpumlanga Province in the 16S rDNA-RFLP analysis.
4

Potencial de esp?cies florestais para remedia??o de substrato contaminado com atrazine e 2,4-D

Fiore, Rebecca de Ara?jo 25 February 2014 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:42:52Z No. of bitstreams: 2 rebeca_araujo_fiore.pdf: 1355098 bytes, checksum: 9068f2cf748b48bb87c50d51c7cdea53 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:43:21Z (GMT) No. of bitstreams: 2 rebeca_araujo_fiore.pdf: 1355098 bytes, checksum: 9068f2cf748b48bb87c50d51c7cdea53 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:43:26Z (GMT) No. of bitstreams: 2 rebeca_araujo_fiore.pdf: 1355098 bytes, checksum: 9068f2cf748b48bb87c50d51c7cdea53 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:43:42Z (GMT) No. of bitstreams: 2 rebeca_araujo_fiore.pdf: 1355098 bytes, checksum: 9068f2cf748b48bb87c50d51c7cdea53 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-01-05T18:43:42Z (GMT). No. of bitstreams: 2 rebeca_araujo_fiore.pdf: 1355098 bytes, checksum: 9068f2cf748b48bb87c50d51c7cdea53 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2014 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Em se tratando da contamina??o de ecossistemas por res?duos de defensivos agr?colas, especial aten??o ? dada para a classe dos herbicidas, em fun??o do volume de aplica??o. Os que possuem mol?culas sol?veis pass?veis de contamina??o de len??is h?dricos subterr?neos se destacam pela abrang?ncia dos efeitos negativos. Nesse sentido, objetivou-se selecionar esp?cies vegetais arb?reas interessantes na remedia??o de ambientes contaminados por res?duos de atrazine e 2,4-D. Foram avaliados 36 tratamentos compostos pela combina??o de 12 esp?cies florestais [Inga marginata (ing?), Schizolobium parahyba (guapuruvu), Handroanthus serratifolius (ip? amarelo), Jacaranda puberula (carobinha), Cedrela fissilis (cedro), Calophyllum brasiliensis (landin), Psidium mirsinoides (goiabinha), Tibouchina glandulosa (quaresmeira), Caesalpinia f?rrea (pau-ferro), Caesalpinia pluviosa (sibipiruna), Terminalia arg?ntea (capit?o) e Schinopsis brasiliensis (bra?na)] e tr?s solu??es simulando o composto lixiviado (atrazine, 2,4-D e ?gua ? controle), com quatro repeti??es. Foram feitas 3 aplica??es dos herbicidas atrazine e 2,4-D com intervalos de 20 dias (aos 60, 80 e 100 dias ap?s o plantio), sendo cada aplica??o correspondente ? metade da dose comercial dos produtos. Para as avalia??es de crescimento foram mensuradas a altura da planta, o di?metro do caule, o n?mero de folhas, a ?rea foliar e o ac?mulo de biomassa seca. Na estimativa do efeito visual dos herbicidas ?s plantas avaliadas, optou-se pela atribui??o de notas em escala de intoxica??o. Para verifica??o de capacidade remediadora das esp?cies arb?reas procedeu-se a semeadura da esp?cie indicadora para indicativo do res?duo do herbicida no solo, (Cucumis sativus (L.)). Posteriormente em amostras de solo provenientes da esp?cie remediadora mais promissora procedeu-se a an?lise de polimorfismo de comprimento de fragmento de restri??o terminal (T-RFLP), com intuito de caracterizar a diversidade microbiana presente. As esp?cies florestais sobreviveram ? aplica??o dos herbicidas, sendo que umas se mostram mais sens?veis do que outras. O ing? apresentou bons resultados de remedia??o com o bioensaio, assim como o ip? amarelo, apesar da sua sensibilidade aos herbicidas. Observou-se aumento no conte?do relativo de macronutrientes para as plantas sob a??o dos herbicidas, na maioria dos tratamentos. Os resultados de T-RFLP confirmaram a diversidade microbiana diferenciada associada ? rizosfera de ing?, principalmente quando submetida ? a??o de atrazine. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT In the case of contamination of ecosystems by residues of pesticides, special attention is given to the class of herbicides, according to the application volume. Those with likely contamination of underground water soluble molecules sheets are distinguished by breadth of negative effects. In this sense, the aim of this work was to select interesting woody plant species in the remediation of contaminated by residues of atrazine and 2,4-D environments. Were evaluated 36 treatments consisted of combinations of 12 forest species [Inga marginata (ing?), Schizolobium parahyba (guapuruvu), Handroanthus serratifolius (ip? amarelo), Jacaranda puberula (carobinha), Cedrela fissilis (cedro), Calophyllum brasiliensis (landin), Psidium mirsinoides (goiabinha), Tibouchina glandulosa (quaresmeira), Caesalpinia f?rrea (pau-ferro), Caesalpinia pluviosa (sibipiruna), Terminalia arg?ntea (capit?o) and Schinopsis brasiliensis (bra?na)] and three leachate solutions simulate the compound ( atrazine , 2,4 - D and water - control),with four replicates each. Three applications of atrazine and 2,4-D were made at intervals of 20 days (at 60, 80 and 100 days after planting), each application was corresponding to half of the recommended. Evaluations of growth were measured plant height, stem diameter, number of leaves, leaf area and dry biomass. In estimating the visual effect of herbicides on plants assessed, was opted for the grading scale of intoxication. To check remediation ability of tree species proceeded seeding indicator species for indication of herbicide residue in the soil (Cucumis sativus (L.)). Later in soil samples from the species most promising remedial proceeded to analysis of length polymorphism terminal restriction fragment (T-RFLP), in order to characterize the microbial diversity present. Forest species survived the herbicide application, and some are more sensitive than others. The ing? had good results with the remediation bioassay, as well as the ipe amarelo, despite their sensitivity to herbicides. Observed increase in the relative content of macronutrients for plants under the effect of herbicides in most treatments. The results of T-RFLP confirmed the differentiated microbial diversity associated with the rhizosphere of ing?, especially when subjected to the action of atrazine.
5

Caracterização da Leishmania infantum e Leishmania (Viannia) braziliensis em cães provenientes da Região Metropolitana do Recife, Pernambuco

MEDEIROS, Rafael Acioli 31 January 2013 (has links)
Submitted by Milena Dias (milena.dias@ufpe.br) on 2015-03-12T17:45:21Z No. of bitstreams: 2 Dissertação Rafael Medeiros.pdf: 841724 bytes, checksum: 770fac09975639de3352fde1d0ea2ec3 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-12T17:45:21Z (GMT). No. of bitstreams: 2 Dissertação Rafael Medeiros.pdf: 841724 bytes, checksum: 770fac09975639de3352fde1d0ea2ec3 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013 / CAPES / As Leishmanioses são uma antropozoonose com ampla distribuição geográfica e ocorrência em torno de 88 países. Na Leishmaniose visceral americana (LVA), os cães domésticos são considerados os principais reservatórios da L. infantum no ambiente domiciliar. Diferentes perfis epidemiológicos da Leishmaniose Tegumentar Americana (LTA) têm sido caracterizados pela presença de casos humanos em áreas de colonizações antigas, sugerindo uma antropozoonose entre os animais domésticos por demonstrarem lesões tegumentares causadas pela Leishmania (Vianna) braziliensis. O diagnóstico das leishmanioses pode ser realizado através de métodos clínicos, epidemiológicos, parasitológicos, imunológicos e moleculares. Em áreas endêmicas o diagnóstico clínico e epidemiológico dessas zoonoses é dificultado pela similaridade clínica com outras doenças, tornando a utilização de exames laboratoriais de suma importância para confirmação diagnóstica. Em virtude da necessidade de diagnóstico especifico das leishmanioses na espécie canina, este trabalho tem como objetivo a utilização da PCR-RFLP, tendo como alvo o espaçador interno transcrito (ITS-1), para diferenciação das espécies de Leishmania em cães provenientes da Região Metropolitana do Recife. Foram coletadas 40 amostras de soro e medula de cães, 30 machos e 10 fêmeas, com idades entre 2 e 7 anos , que apresentaram suspeita clinica de leishmaniose quando atendidos no Hospital Veterinário da UFRPE. Foram realizados os testes diagnósticos de exame direto em medula e Reação indireta de imunoflorescência tanto para LTA quanto LVA. Além disso foi realizado a PCR-RFLP nas amostras de soro e urina para a pesquisa de L. infantum e L. (viannia) braziliensis. Dos 40 cães pesquisados 23 foram positivos para L.infantum e 17 foram negativos para as duas espécies pesquisadas. Quando comparado com os testes diagnósticos convencionais , 3 dos 23 cães foram positivos apenas na técnica molecular. Portanto, a ITS1-PCR RFLP pode ser uma importante ferramenta para o diagnostico e caracterização da leishmaniose canina em uma determinada região.
6

The application of biotechnology toward the genetic improvement of oil palm

Mayes, Sean January 1995 (has links)
No description available.
7

Genome analysis of Hordeum bulbosum L. and hybrids with H. vulgare L

Jaffe, Benjamin January 1998 (has links)
No description available.
8

Development of a 16S rRNA PCR-RFLP Assay for Bartonella Identification: Applicability in the Identification of Species Involved in Human Infections

Del Valle, Luis J., Jaramillo, Michael L., Talledo, Miguel, Pons, Maria J., Flores, Lidia, Quispe, Ruth L., Ramírez, Pablo, García de la Guarda, Ruth, Alvarado, Débora, Espinoza-Culupú, Abraham, Del Valle Mendoza, Juana, Vargas, Martha, Ruíz, Joaquim 02 July 2014 (has links)
Abstract We designed a 16S rRNA gene PCR-RFLP scheme to identify all currently described Bartonella spp. The 16S rRNA genes of all Bartonella spp. were in-silico analyzed in order to design a RFLP technique able to discriminate among different species. The restriction enzymes selected were MaeIII, MseI, Sau96I, BsaAI, DrdI, FokI, BssHII, BstUI, AluI, TspDTI and HphI which, according to a decision-making tree, facilitated the differentiation of all the currently described species of Bartonella.The technique was experimentally tested in different species of Bartonella, including human pathogenic B. bacilliformis and B. henselae with a 100% of concordance with the in-silico predicted patterns.This novel RFLP assay could be used to identify both human and non-human pathogenic Bartonella in diagnostic, phylogenetic and epidemiologic studies.
9

Water quality and eukaryotic plankton dynamics in the Mission-Aransas Estuary, Texas from 2011-2012

Lashaway, Aubrey Rain 11 November 2013 (has links)
As the base of the food chain, plankton affect the cycling of nutrients and organic matter within ecosystems and support production at higher trophic levels. The overall goal of this project was to examine how natural water quality fluctuations, such as changes in nutrients, temperature, and salinity, influence estuarine plankton community structure. To achieve this, I examined water quality as well as the diversity and biomass of eukaryotic plankton communities in a subtropical estuary located within the Mission-Aransas National Estuarine Research Reserve. The sampling sites included in this study consisted of three bay (Copano Bay West, Copano Bay East, Aransas Bay) and two river (Mission River Estuary, Aransas River Estuary) estuary sites. Water samples were collected monthly at the five sites from September 2011 to August 2012 and analyzed for a suite of abiotic and biotic variables. Eukaryotic plankton diversity and community structure were evaluated by using the terminal restriction fragment length polymorphism (t-RFLP) method. Although a narrow salinity gradient was present at the sampling sites, seasonal changes in water quality conditions were observed. In the river estuaries, water quality parameters defined three significant temporal periods at the Mission River Estuary site, whereas only one month differed at the Aransas River Estuary site, indicating little seasonal variation. The Copano Bay sites exhibited a seasonal pattern consisting of four periods, marked by a distinct fall (October, November, December) grouping, while Aransas Bay showed a seasonal pattern consisting of three periods, with no fall group. Even though the water quality conditions define different monthly groupings in the bay and river estuary sites, the same parameters – DOC, TDN, and pH – are the strongest drivers of the patterns at all of the sites. Seasonal and spatial distinctions in the Mission-Aransas Estuary eukaryotic plankton community composition were determined using t-RFLP. Frequent shifts in composition were apparent across samples collected at approximately bi-weekly to monthly intervals. There were significant differences (ANOSIM, p < 0.05) in community composition between the Aransas and Mission River Estuary and Aransas Bay sites. Although the overall ANOSIM tests show significance between eukaryotic plankton communities monthly and between the bay water quality periods, none of the pairwise comparisons were significantly different. However, the ANOSIM R-statistic for the monthly pairwise comparisons displays a general increasing trend over time from sampling, further highlighting the dynamic nature of the microbial eukaryotic assemblage within sites. / text
10

Phylogenetics and molecular identification of the Ochlerotatus communis and Oc. punctor complexes (Diptera: Culicidae)

Hosseinzadeh Namin, Hooman 10 September 2013 (has links)
Accurate identification of pathogens and vectors is essential in epidemiological studies of mosquito-borne pathogens. However, the members of the communis and punctor complexes are difficult to distinguish because they are highly cryptic species, with little to no species-specific morphological characters. The objective of this thesis is to develop molecular tools, including RFLP and DNA barcoding using cytochrome oxidase I (COI), internal transcribed spacer 2 (ITS2) and the intron of ribosomal protein S12 (RPS12) to facilitate identification of the members of these two complexes in Manitoba. A distinct interspecific distance for COI was found between the members of the communis complex included here, and diagnostic RFLP profiles were developed for Oc. communis and Oc. churchillensis. Relatively low average interspecific genetic distances using COI, ITS2 and RPS12 were observed between the members of the punctor complex, indicates no discernable boundaries between these species based on DNA barcoding.

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