A national inventory of UK plant genetic resources carried out in 2003-4 covered surveys and documentation of landrace types, occurrences and threats. Among the local varieties found, those with longest histories of local cultivation occurred on the most remote Scottish islands: the Outer Hebrides and Tiree had bere (Hordeum vulgare L.), Small oat (Avena strigosa Schreb.) and rye (Secale cereale L.); bere and Small oat on Orkney and Shetland; and Shetland cabbage (B. olearacea L.) on Shetland. These landraces are not only geographically but also agriculturally marginal; they are confined to crofting agriculture and used in low-intensity pastoralism. Two of these, the oat and the cabbage, were chosen for a characterization study which formed the major part of this PhD thesis. The broad aims of the characterization study were first, to describe the existing diversity within Scotland; to document the ex situ collection of Scottish landraces; to better understand genetic structure and dynamics of the landraces; but also to explore the use of a characterization study to raise awareness about landraces. Morphological and microsatellite results showed distinct identities for both landraces in relation to the respective outgroups; in the oat distinct regional identities were found. High diversity was found, most of the genetic variation however, was within populations, for both inbreeder (oat) and outbreeder (cabbage). This can be attributed to frequent and widespread seed exchange and seed swapping within island groups, while the small but significant regional distinctness is maintained through isolation between the three islands groups. The morphological characterization of Small oats was carried out in situ, on a croft in the Southern Outer Hebrides, aiming at education and raising awareness about landraces among secondary school students, maintainers and the local public in general. The extension and education element of the study seemed useful in raising the issue of landraces locally. Carrying out the trial in the area of origin and amidst maintainers had the additional advantage of identifying and communicating with stakeholders groups. Integrated conservation of ex situ collection and maintainers has been achieved through the Scottish Landrace Protection Scheme. By retaining the link between landraces and maintainers during the characterization, a springboard may have been created for feedback of the genetic results into the local seed system and to discuss further support options for landraces and maintainers.

Master of Science / Department of Agronomy / Allan Fritz / Fusarium head blight (FHB) is one of the most devastative diseases in wheat. Growing resistant cultivars is one of the most effective strategies to minimize the disease damage. Huangcandou (HCD) is a Chinese wheat landrace showing a high level of resistance to FHB spread within a spike (type II). To identify quantitative traits loci (QTL) for resistance in HCD, a population of 190 recombinant inbred lines (RILs) were developed from a cross between HCD and Jagger, a susceptible hard winter wheat (HWW) released in Kansas. The population was evaluated for type II resistance at the greenhouses of Kansas State University. After initial marker screening, 261 polymorphic simple-sequence repeats (SSR) between parents were used for analysis of the RIL population. Among three QTL identified, two from HCD were mapped on the short arms of chromosomes 3B (3BS) and 3A (3AS). The QTL on the distal end of 3BS showed a major effect on type II resistance in all three experiments. This QTL coincides with a previously reported Fhb1, and explained 28.3% of phenotypic variation. The QTL on 3AS explained 9.7% of phenotypic variation for mean PSS over three experiments. The third QTL from chromosome 2D of Jagger explained 6.5% of phenotypic variation. Allelic substitution using the closest marker to each QTL revealed that substitution of Jagger alleles of two QTL on 3AS and 3BS with those from HCD significantly reduced the PSS. HCD containing both QTL on 3AS and 3BS with a large effect on type II resistance can be an alternative source of FHB resistance for improving FHB type II resistance in wheat. Besides, meta-analyses were used to estimate 95% confidence intervals (CIs) of 24 mapped QTL in five previously mapped populations derived from Chinese landraces: Wangshuibai (WSB), Haiyanzhong (HYZ), Huangfangzhu (HFZ), Baishanyuehuang (BSYH) and Huangcandou (HCD). Nineteen QTL for FHB type II resistance were projected to 10 QTL clusters. Five QTL on chromosomes 1A, 5A, 7A, and 3BS (2) were identified as confirmed QTL that have stable and consistent effects on FHB resistance and markers in these meta-QTL regions should be useful for marker-assisted breeding.

This thesis contains the results of a biocultural conservation research conducted between 2008 and 2011 in home gardens in Vall Fosca, Catalan Pyrenees, northeastern Spain. Vall Fosca is a valley where traditional agroecosystems still survive, but whose inhabitants are divided in defining the most suitable development model for the region. This dissertation examines the existence of landraces and knowledge associated with them in a rural area in an industrialized country. It shows who preserves landraces and why they do so. It also estimates the association between individual centrality in the network of seed exchange and conservation of landraces and associated knowledge. This thesis also discusses the ecosystem services provided by home gardens, as well as the differences between men and women when assessing these ecosystem services. The results establish the existence of landraces and knowledge associated with them in a rural area in an industrialized country. Specifically, my results show the existence of 39 landraces belonging to 31 species, in home gardens with a variety of 148 different species. Women, people over 65 years of age, experienced gardeners and people who grow the garden with organic techniques conserve more landraces than people without these characteristics. Also people who have a more active role in the seed exchange network and have higher levels of intermediation in the network retain more landraces and traditional knowledge than people who have a more passive role in social networks of seed exchange. Home gardens provide a wide range of services, often not very prominent in the literature on ecosystem services. Among these, cultural services are the most appreciated. In this regard, an interesting contribution of this work is that the most valued home garden ecosystem services differ significantly from the services provided by other farming systems. Another interesting contribution of this work is that women value the ecosystem services more than men. The explanation for this finding is part of the socialization theory that assigns women roles on family care and protection. My analysis provides new data that facilitate the understanding of the relationship between pro-environmental attitudes and gender socialization. This thesis has found that home gardens and landraces are symbols of cultural identity in the valley and that both permanent residents and visitors consider that home gardens are key elements in the landscape of the valley and should be preserved as part of biocultural heritage. In addition, the ecosystem services provided by the home gardens, particularly the cultural services, can help develop relations between people, relations that might contribute to strengthening cultural identity and to create bonds of respect with the environment. The results of this thesis can contribute to make biocultural diversity visible in the valley and generate endogenous rural development models based on the sustainable exploitation of ecosystem services generated by traditional agroecosystems. Key words: ecosystem services; landraces; rural development; socialization theory; Spain; traditional ecological knowledge. / La presente tesis recoge una investigación en conservación biocultural realizada entre el 2008 y el 2011 en los huertos domésticos de la Vall Fosca en el Pirineo catalán, nordeste de España. La Vall Fosca es un valle en el que aún perviven agroecosistemas tradicionales, pero que se encuentra dividido a la hora de definir el modelo de desarrollo más deseable. Esta tesis analiza la existencia de cultivos de manejo local y el conocimiento asociado a ellos en un área rural de un país industrializado; muestra quién y por qué se conservan los cultivos de manejo local; y estima la asociación entre la centralidad individual en la red de intercambio de semillas y la conservación de los cultivos de manejo local y su conocimiento asociado. En esta tesis también se analizan los servicios ambientales proporcionados por los huertos domésticos, así como las diferencias entre hombres y mujeres en el momento de valorar estos servicios ambientales. Los resultados del análisis establecen la existencia de cultivos de manejo local y el conocimiento asociado a ellos en un área rural de un país industrializado. Específicamente mis resultados muestran la existencia de 39 cultivos de manejo local correspondientes a 31 especies, en huertos con una diversidad de 148 especies diferentes. Las mujeres, las personas de más de 65 años de edad, los hortelanos con experiencia, y la gente que cultiva el huerto con técnicas orgánicas mantienen más cultivos de manejo local que las personas sin estas características. Asimismo las personas que tienen un papel más activo en las redes de intercambio de semillas y que tienen mayores niveles de intermediación en la red, también conservan más cultivos de manejo local y tienen mayor conocimiento tradicional que las personas que tienen un papel más pasivo en las redes sociales. Los huertos domésticos proporcionan un amplio abanico de servicios, a menudo poco destacados en la literatura. Entre estos, los servicios culturales son los más apreciados. Un aporte interesante en este sentido es que los servicios de los huertos domésticos más valorados difieren significativamente de los servicios proporcionados por otros sistemas agrícolas. Otro aporte interesante de este trabajo es que las mujeres valoran los servicios ambientales más que los hombres. La explicación a este hallazgo se enmarca en la teoría de la socialización, que asigna a las mujeres papeles de cuidado y protección. Este análisis aporta nuevos datos que facilitan el entendimiento de la relación entre actitudes pro-ambientales y la socialización de género. En esta tesis se ha podido comprobar que los huertos y los cultivos de manejo local son símbolos de identidad cultural en el valle y que tanto los habitantes permanentes como los visitantes consideran que los huertos son elementos clave en el paisaje del valle y que se deberían preservar como parte de su patrimonio biocultural. Además, los servicios ambientales proporcionados por los huertos, en particular los culturales, pueden ayudar a tejer relaciones entre las personas que contribuyan a fortalecer la identidad cultural y a crear lazos de respeto con su medio ambiente. Los resultados de esta tesis pueden contribuir a visibilizar la diversidad biocultural del valle y generar modelos endógenos de desarrollo rural basados en la explotación sostenible de los servicios ambientales generados por los agroecosistemas tradicionales. Palabras clave: conocimiento ecológico tradicional; cultivos de manejo local; desarrollo rural; España; servicios ambientales; teoría de la socialización; variedades locales. / Aquesta tesi recull una investigació en conservació biocultural realitzada entre el 2008 i el 2011 en els horts domèstics de la Vall Fosca al Pirineu català, nord-est d'Espanya. La Vall Fosca és una vall en la qual encara perviuen agroecosistemes tradicionals, però que es troba dividida a l'hora de definir el model de desenvolupament més desitjable. Aquesta tesi analitza l'existència de cultius de gestió local i el coneixement associat a ells en una àrea rural d'un país industrialitzat; mostra qui i per què es conserven els cultius de gestió local, i estima l'associació entre la centralitat individual a la xarxa d’ intercanvi de llavors i la conservació dels cultius de gestió local i el seu coneixement associat. En aquesta tesi també s'analitzen els serveis ambientals proporcionats pels horts domèstics, així com les diferències entre homes i dones en el moment de valorar aquests serveis ambientals. Els resultats de l'anàlisi estableixen l'existència de cultius de gestió local i el coneixement associat a ells en una àrea rural d'un país industrialitzat. Específicament els meus resultats mostren l'existència de 39 cultius de gestió local corresponents a 31 espècies, en horts amb una diversitat de 148 espècies diferents. Les dones, les persones de més de 65 anys d'edat, els hortolans amb experiència, i la gent que conrea l'hort amb tècniques orgàniques mantenen més cultius de gestió local que les persones sense aquestes característiques. Així mateix les persones que tenen un paper més actiu en les xarxes d'intercanvi de llavors i que tenen majors nivells d'intermediació a la xarxa, també conserven més cultius de gestió local i tenen major coneixement tradicional que les persones que tenen un paper més passiu en les xarxes socials. Els horts domèstics proporcionen un ampli ventall de serveis, sovint poc destacats en la literatura. Entre aquests, els serveis culturals són els més apreciats. Una aportació interessant en aquest sentit és que els serveis dels horts domèstics més valorats difereixen significativament dels serveis proporcionats per altres sistemes agrícoles. Un altre aportació interessant d'aquest treball és que les dones valoren els serveis ambientals més que els homes. L'explicació a aquesta troballa s'emmarca en la teoria de la socialització, que assigna a les dones papers de cura i protecció. Aquesta anàlisi aporta noves dades que faciliten l'enteniment de la relació entre actituds pro-ambientals i la socialització de gènere. En aquesta tesi s'ha pogut comprovar que els horts i els conreus de gestió local són símbols d'identitat cultural a la vall i que tant els habitants permanents com els visitants consideren que els horts són elements clau en el paisatge de la vall i que s'haurien preservar com a part del seu patrimoni biocultural. A més, els serveis ambientals proporcionats pels horts, en particular els culturals, poden ajudar a teixir relacions entre les persones que contribueixin a enfortir la identitat cultural i a crear llaços de respecte amb el seu medi ambient. Els resultats d'aquesta tesi poden contribuir a visibilitzar la diversitat biocultural de la vall i generar models endògens de desenvolupament rural basats en l'explotació sostenible dels serveis ambientals generats pels agroecosistemes tradicionals. Paraules clau: coneixement ecològic tradicional; cultius de gestió local, desenvolupament rural, Espanya, serveis ambientals, teoria de la socialització; varietats locals.

Crop yields are coming under pressure to continue to grow in the face of climate change, competition, disease and pressure to reduce inputs. Photosynthetic efficiency is being targeted for improvement to increase yields. This study examined the variation in parameters of photosynthetic efficiency including canopy structure (leaf length, canopy angle, and chlorophyll content and growth rate) and gas exchange (photosynthetic rate, stomatal density and chlorophyll fluorescence) in Spring Barley (Hordeum vulgare ssp vulgare). These were first established for modern cultivars representing the most widely grown lines in the last 60 years. As cultivars are developed from a small pool of parents they may have limited genetic variation available for breeding. Landraces have been suggested as sources of variation. Using field and growth cabinet based studies the photosynthetic efficiencies of canopy structure and gas exchange were established for a range of European landraces under high and low nutrient inputs. This study demonstrated that in modern cultivars the leaf length increased with year of release from 23.2 to 29.6 cm and the chlorophyll content decreased from 46.9 to 34.8 SPAD units. Once the ear had emerged no difference was seen in canopy structure or photosynthetic rate. There was variation in landrace canopy establishment rate, leaf angle and number of leaves present within the canopy. The landraces from Northern European latitudes pushed though booting and reached full canopy establishment up to 8 days sooner than those from Southern Europe. This may be a response to a shorter growth season at Northern latitudes requiring the canopy to be established quickly. The landraces held the leaves within their canopy in a more horizontal position than the Southern European lines with leaf angle ranging from 18-45 degrees at GS39 and 31-84 degrees at GS59. This regressed negatively with temperature so it may be that a vertical canopy structure is beneficial in areas with higher temperatures. The photosynthetic rate of the landraces showed no variation but when chlorophyll fluorescence examined the efficiency of photosystem II (PSII) there was a positive regression of Fv/Fm ratio with latitude. This suggested that lines from Southern Europe were experiencing a greater stress with a ratio of up to 0.822 compared to those lines from the North with ratios from 0.767. The stomatal density of the landraces showed a large difference in ranges from 22-41 stomata between the lines. When high and low nutrient inputs were compared reductions from a ratio of 0.48 to 0.47 in Harvest Index and from 55g to 52g in 1000 grain weight were seen. The chlorophyll content of the lines was also reduced from 41.7 to 39.2 SPAD units at GS39 and from 44.9 to 39.8 SPAD units at GS59 by the reduction in nutrient inputs which may be a result of less N available for the production of chlorophyll. In conclusion there is variation present in canopy structure in European landraces that may be useful for future breeding or in identifying landrace collections which could be targeted for traits of interest in photosynthetic efficiency. These landraces may provide traits which could be used to develop cultivars which are locally adapted to climate and environmental conditions.

The exact origin of the peculiar naked barley is somewhat illusive. There   is a debate whether it has a single, monophyletic origin or a multiple, paraphyletic origin. It is from previous Asian studies on naked   barley known that a mutation   or a deletion of the nud gene expresses the   naked seed phenotype. Not much   investigation has been done outside of   Asia, least of all in the Nordic countries, on what gives naked   barley its character. Therefore this   study was set up to examine if   the Nordic variant of naked barley shares   the same nud allele as the Asian   and thus has a   close connection with it, or   if they have independent mutations. I   could confirm that the known alleles of the nud gene do determine the seed character of barley. Most of the   results of the PCR genotyping confirmed the phenotype of the tested   accessions, both naked and hulled barleys. However, one visually phenotyped naked   barley cultivar (NGB4580) still amplified with the known primers that would   match the Asian hulled allele, meaning that the Nordic accession NGB4580 of   naked barley did not carry the known nud   deletion. This suggests that naked barley has arisen independently in Asia   and in the Nordic countries.

Thyroid hormones are known to be important in several processes in chicken, such as growth, metabolism and reproductive system. In previous studies the thyroid stimulating hormone receptor (TSHR)-gene has been identified as a target for a selective sweep in commercial breeds of chicken such as broiler and White Leghorn. The evolution of domesticated species can be split into three periods. The first is the natural selection in their natural habitat, the second the beginning of the domestication process, when humans started to tame and breed the wild animals and the third is when animals were bred for commercial interests such as egg laying properties and meat production in chicken. Landraces, which are domesticated but not commercially bred races, are a great resource for identifying during which period a specific gene, which differs between wild type and commercial bred breeds, were selected. In this study Swedish landrace chickens were used in order to analyze the importance of a mutation in the TSHR-gene in the domestication process. The results of this study gave that all, except two individuals from the Bohuslän-Dals svarthöna were homozygous for the mutation known from commercial breeds. The two individuals from Bohuslän-Dals svarthöna were both heterozygous for the mutation. These results suggest that the TSHR mutation is important for the domestication process and were already more or less fixed at the commencement of commercial breeding. The mutation is thought to be dominant and to have an inhibitory impact on the TSHR activity. This might result in hypothyroidism which would make alterations in the reproductive system. This is plausible because the constant availability of food in captivity makes the seasonal reproductive system no longer critical for survival of progeny.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / The black aphid stands out as one of the most important pests of cowpea, as it causes direct and indirect damages to the plant. A measure of efficient control and easy to use by producers is resistant varieties, which have the ability to reduce infestation or damage caused by this insect. In this sense, this work had the purpose of seeking new sources of cowpea genotypes resistant to black aphid, preserved by farmers, in two distinct regions of the State of Cearà (Cariri and Curu Valley) and landraces collected sparsely in some states of the Northeast. The experiment was conducted in a greenhouse in the UFC-Fortaleza and IFCE - Umirim with a randomized complete block design with four replications, testing seventy-one genotypes distributed in three tests according to the collection area. For comparison, in each assay, were used four genotypes with known resistance. To evaluate the resistance of genotypes, we used the following variables: number of live adults, number of live nymphs and the effective resistance. The results indicated 10 highly resistant genotypes: Rabo-de-tatu (CCE-115), Corujinha (CCE-055), Leandro-do-monte (CCE-112), Paulistinha (CCE-068) Branco-do-marinheiro (CCE-078), Costela-de-vaca (CCE-046), Recife-marrom (CCE-094) Rabo-de-peba (CCE-118), Moitinha (CCE-077) and Passo II (SCC-091), which represent a source resistance to black aphid and may be used in genetic improvement of the cowpea around the world, through backcrossing. Finally, it was found that in all regions studied, there was found cowpea genotypes resistant to Aphis craccivora and, independent of the area, where they were collected, it was found genetic diversity. The mechanisms involved in genotypes resistance to adult aphids may possible be antibiosis and / or antixenosis and for nymphs the results indicate antibiosis. / O pulgÃo-preto destaca-se como uma das mais importantes pragas do feijÃo-de-corda, por causar danos diretos e indiretos Ãs plantas. Uma medida de controle eficiente e de fÃcil emprego pelo produtor à a utilizaÃÃo de variedades resistentes, que tÃm a possibilidade de reduzir a infestaÃÃo ou os danos causados por este inseto. Nesse sentido, esta pesquisa objetiva-se buscar novas fontes de resistÃncia ao pulgÃo-preto e inferir que mecanismos de resistÃncia poderiam estar envolvidos, em genÃtipos de feijÃo-de-corda preservados por agricultores, de duas regiÃes distintas do Estado do Cearà (regiÃo do Cariri e Vale do Curu) e em materiais coletados, dispersamente, por alguns estados do Nordeste. O experimento foi conduzido em telado na UFC-Fortaleza e no IFCE â Umirim, com delineamento em blocos ao acaso, com quatro repetiÃÃes e setenta e um tratamentos, distribuÃdos em trÃs ensaios, conforme a regiÃo de coleta. Para efeito de comparaÃÃo, em cada ensaio, foram testados quatro genÃtipos padrÃes, com resistÃncia conhecida. Para avaliar a resistÃncia dos genÃtipos, as seguintes variÃveis foram usadas: nÃmero de adultos vivos, nÃmero de ninfas vivas e Resistencia efetiva. Os resultados indicaram 10 genÃtipos altamente resistentes, â Rabo-de-tatu (CCE-115), Corujinha (CCE-055), Leandro-do-monte (CCE-112), Paulistinha (CCE-068), Branco-do-marinheiro (CCE-078), Costela-de-vaca (CCE-046), Recife-marrom (CCE-094), Rabo-de-peba (CCE-118), Moitinha (CCE-077) e Passo II (CCE-091), e que representam fonte de resistÃncia ao pulgÃo-preto e podem ser utilizados para melhoramento genÃtico do feijÃo-de-corda, em todo o mundo, atravÃs de retrocruzamentos. Ao final, verificou-se que, em todas as regiÃes estudadas, foram encontrados genÃtipos de feijÃo-de-corda resistentes ao Aphis craccivora e que, independentemente das regiÃes de coleta, existe diversidade genÃtica. Os provÃveis mecanismos de resistÃncia envolvidos sÃo antibiose e/ou antixenose para adultos e antibiose para ninfas.

Made available in DSpace on 2014-08-20T14:33:04Z (GMT). No. of bitstreams: 1 dissertacao_walter_fagundes_rodrigues.pdf: 9250647 bytes, checksum: cb151d7e3de030ab73edd934e2a75088 (MD5) Previous issue date: 2012-03-23 / The objective of this study was to demonstrate the agrobiodiversity of cucurbits, maize (Zea mays) and beans (Phaseolus vulgaris), and methods of management and farming practices used, both for their production and conservation of genetic resources, based on farmers ecological basis of the southern Rio Grande do Sul visits were carried out on 11 family farms, and through interviews, 37 landraces were collected which were duly cataloged and stored in Active Germplasm Bank of Embrapa Clima Temperado. / O objetivo deste trabalho foi resgatar a agrobiodiversidade de cucurbitáceas, milho (Zea mays) e feijão (Phaseolus vulgaris), e os métodos de manejo e práticas agrícolas utilizados, tanto para sua produção como para a conservação dos propágulos desses recursos genéticos, tendo como base agricultores de base ecológica da região sul do Rio Grande do Sul. Foram realizadas visitas em 11 propriedades agrícolas familiares, e através de entrevistas semidirecionadas foram coletadas 37 variedades crioulas que foram devidamente catalogadas e conservadas em Bancos Ativos de Germoplasma da Embrapa Clima Temperado.

Made available in DSpace on 2014-08-20T14:06:16Z (GMT). No. of bitstreams: 1 Dissertacao_Daniela_Priori.pdf: 1667098 bytes, checksum: 34e76681ceb9a2d408f534549b9ee012 (MD5) Previous issue date: 2011-02-25 / Genetic resources conserved in genebanks have a great value in terms of conservation of rare types, when they are threatened by abandonment of farming or as a unique resource for plant breeding programs. Among the accessions conserved in genebanks important sources of genetic variability can be found for obtaining more productive genotypes tolerant to biotic and abiotic stresses and improved nutritional quality. To have success in that demand is necessary that the accessions contained in genebanks are characterized and evaluated in terms of both qualitative and quantitative characters. The characterization and evaluation of accessions conserved in genebanks must be priorities in the strategy for management of genetic resources, as they provide better knowledge of the germplasm available, is essential for use in breeding programs. In Brazil, there is little information on genetic resources of Cucurbits, especially as regards Cucurbita ficifolia, Cucurbita argyrosperma. Large number of Cucurbita landraces grown in the country could be better exploited as sources of genes for breeding programs, after genetic characterization. Much of the genetic diversity of different Cucurbita landraces grown in southern Brazil has been lost due to neglect of cultivation or its replacement by commercial hybrid varieties. This work was carried in order to contribute to general knowledge related to genetic resources of Cucurbita argyrosperma, Cucurbita ficifolia and Cucurbita pepo, and with specific objectives to assess the transferability of primers designed to C. pepo in C. argyrosperma and C. ficifolia and to evaluate the genetic variability within and among landraces of C. pepo grown in Rio Grande do Sul through analysis of microsatellite markers. Ten accessions of C. pepo, nine of C. argyrosperma and five of C. ficifolia belonging to the Active Germplasm Bank of Cucurbitaceae from Embrapa Temperate Agriculture were submitted to molecular characterization. The genetic distance between these accessions was determined. The transferability of SSR loci from C. pepo to C. argyrosperma and C. ficifolia was 85% and 80% respectively. The analysis of these 24 accessions with 35 loci generated a total of 105 SSR markers, ranging from one to four alleles per locus, of which 56 (53,33%) were polymorphic, showing that there is genetic diversity in the accessions analyzed. The presence and absence of markers allowed to find 100 loci, varying from one to five alleles per locus, with overall average of three alleles per marker analyzed. Among the 34 loci tested, 29 (85.2%) were polymorphic, showing that there is genetic variability among the accessions of C. pepo analyzed. Data evaluation was done by molecular analysis of molecular variance (AMOVA). It was observed that 54.60% of genetic variability is attributable to variation between accessions and 45.39% is attributed to differences within accessions. A comparative analysis was made between the ten accessions studied, analyzed two by two by AMOVA. From 45 comparisons between the ten accessions significant differences there were detected between 35 comparisons, with average of 57.10% of molecular variation attributed to differences between accessions. Genetic variation among counties where the accessions were collected was not significant, indicating that there is not population subdivision according to geographic region. Results indicate that the microsatellites were efficient for the characterization and molecular analysis of genetic divergence. These studies contributed to increase the knowledge related to these genetic resources. SSR primers developed for Cucurbita pepo can be used for molecular characterization of C. argyrosperma and C. ficifolia. Landraces of C. argyrosperma and C. ficifolia showed low genetic variation, while C. pepo shows great variability. The largest proportion of variability in C. pepo is distributed between accessions and not within accessions. / Os recursos genéticos conservados em bancos de germoplasma apresentam grande valor do ponto de vista da conservação de tipos raros, quando os mesmos são ameaçados pelo abandono do cultivo ou como recurso insubstituível para programas de melhoramento genético vegetal. Dentre os acessos contidos nos bancos de germoplasma podem ser encontradas importantes fontes de variabilidade genética para a obtenção de genótipos mais produtivos, tolerantes a estresses bióticos e abióticos e com melhor qualidade nutricional. Para que haja sucesso nessa demanda é necessário que os acessos contidos nos bancos de germoplasma sejam caracterizados e avaliados, tanto em termos de caracteres qualitativos quanto quantitativos. No Brasil, há pouca informação sobre os recursos genéticos de Cucurbitáceas, de modo especial no que se refere à Cucurbita argyrosperma e Cucurbita ficifolia. Grande número de variedades locais de Cucurbita cultivadas no país poderiam ser melhor exploradas como fontes de genes para programas de melhoramento, após a devida caracterização. Muito da diversidade genética das variedades locais de diferentes espécies de Cucurbita cultivadas no Sul do Brasil vem sendo perdida devido ao abandono do cultivo ou à sua substituição por variedades híbridas comerciais. Este trabalho foi realizado com o objetivo geral de contribuir para o conhecimento relacionado aos recursos genéticos de Cucurbita argyrosperma, C. ficifolia e C. pepo, e objetivos específicos de avaliar a transferibilidade de loci de microssatélites de C. pepo para C. argyrosperma e C. ficifolia; e avaliar a variabilidade genética entre e dentro de variedades locais de C. pepo cultivadas no Rio Grande do Sul por meio da análise de marcadores microssatélites. Foram analisados dez acessos de C. pepo, nove de C. argyrosperma e cinco de C. ficifolia do acervo do Banco Ativo de Germoplasma de Cucurbitáceas da Embrapa Clima Temperado. A distância genética entre esses acessos foi determinada. A transferibilidade de locos SSR de C. pepo para C. argyrosperma e C. ficifolia foi de 85% e 80%, respectivamente. A análise dos 24 acessos de Cucurbita por meio de 35 loci SSR gerou um total de 105 marcadores SSR, com variação de um a quatro alelos por loco, dos quais 56 (53,33%) foram polimórficos, evidenciando que há diversidade genética entre os acessos analisados. Através dos dados de presença e ausência de marcadores obtidos com 34 combinações de primers, foram encontrados 100 locos com variação de um a cinco alelos por loco, com média geral de três alelos por marcador analisado. Dentre os 40 locos analisados, 29 (85,3%) foram polimórficos, evidenciando que há variabilidade genética entre os acessos de C. pepo analisados. A avaliação dos dados moleculares foi feita pela análise molecular da variância (AMOVA). Deste modo, foi possível verificar que 54,60% da variabilidade genética é atribuída à variação entre acessos e 45,39% é atribuída a diferenças dentro dos acessos. Foi feita a análise comparativa entre os dez acessos estudados, analisados dois a dois, pela análise AMOVA. Das 45 comparações entre os dez acessos, foram significativas as diferenças entre 35 delas, com média de 57,10% da variação molecular atribuída às diferenças entre acessos. A variação genética entre os municípios onde os acessos foram coletados não foi significativa, indicando que não ocorre subdivisão de populações em função da região geográfica. Os resultados obtidos indicam que os microssatélites foram eficientes para a caracterização molecular e a análise da divergência genética. É possível utilizar primers de microssatélites desenvolvidos para C. pepo na caracterização molecular de C. argyrosperma e C. ficifolia. Variedades locais de C. argyrosperma e C. ficifolia apresentam pouca variabilidade genética, enquanto que C. pepo evidencia grande variabilidade genética. A maior proporção da variabilidade em C. pepo encontra-se distribuída entre os acessos, e não dentro dos acessos.

Made available in DSpace on 2017-07-21T19:59:51Z (GMT). No. of bitstreams: 1 Dayane Molin.pdf: 2944692 bytes, checksum: a8d299024aefbd42062cb84bd7720a9d (MD5) Previous issue date: 2012-02-23 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / The wide variability in corn is due to the numerous landraces, important genotypes for breeding programs, because they constitute a source of genetic variability in the exploration of new genes of economic interest. The objectives were to analyze the genetic diversity between landraces from Rio Grande do Sul and Paraná through the analysis of polymorphism generated by RAPD, microsatellite (SSR) and AFLP markers; cluster these genotypes through estimates of genetic similarity and establish possible relationships between genetic similarity and the sampling sites of the landraces. PCR reactions for each marker were optimized through specific protocols being used: 30 RAPD primers, 47 SSR primers pairs and 25 combinations of primers for the EcoRI + MseI for the AFLP marker. The amplified fragments (RAPD and SSR) were visualized in agarose gel at 2 and 3 %, respectively, through horizontal electrophoresis run for approximately 4 h at 80 V. The AFLP amplification products were resolved on a polyacrylamide gel (6 %) submitted to a vertical electrophoresis run for 3 h 30 min at 80 W (1500 V). Genotyping of the varieties of corn with the RAPD marker amplified 409 fragments with a polymorphism average rate of 81.9 %. The SSR generated 134 fragments with 78.3 % of polymorphism. On the other hand, the AFLP amplified 1889 fragments with a polymorphism average rate of only 40.3 %. The polymorphic fragments were submitted to analysis of genetic similarity using the Jaccard coefficient and UPGMA clustering method individually and jointly for all markers. The coefficient mean of similarity was 57 % for RAPD, 56 % for SSR, 74 % for the AFLP and 69 % for the joint analysis. The dendrograms obtained from RAPD and SSR showed 8 different groups, while the dendrogram obtained from AFLP and the joint analysis formed six and seven groups, respectively. In general, the correlations between the similarity matrices were low, but between the AFLP and combined analysis was 96 %. Results revealed a wide genetic variability among landraces. The RAPD and SSR had the highest average rates of polymorphism and AFLP showed the highest rates of genetic similarity among landraces. In general, the markers used were effective tools for sampling the genetic diversity and cluster varieties according to the sampling sites, although they have differential capacity to reveal polymorphism as well as to cluster the landraces. / A ampla variabilidade existente em milho deve-se às inúmeras variedades crioulas, genótipos importantes para o melhoramento, pois constituem fonte de variabilidade genética na prospecção de novos genes de interesse econômico. Os objetivos deste trabalho foram analisar a diversidade genética existente entre acessos de milho crioulo oriundos do Rio Grande do Sul e do Paraná a partir da análise do polimorfismo gerado pelos marcadores RAPD, microssatélite (SSR) e AFLP; realizar o agrupamento destes genótipos através das estimativas da similaridade genética e estabelecer possíveis relações entre a similaridade genética e os locais de coleta das variedades crioulas. As reações de PCR para cada marcador foram otimizadas através de protocolos específicos, sendo utilizados: 30 primers RAPD, 47 pares de primers SSR e 25 combinações de primers EcoRI + MseI para o marcador AFLP. Os fragmentos amplificados (RAPD e SSR) foram visualizados em gel de agarose a 2 e 3 %, respectivamente, através de corrida eletroforética horizontal por aproximadamente 4 h a 80 V. Os produtos da amplificação do AFLP foram resolvidos em gel de poliacrilamida (6 %) submetidos à corrida eletroforética vertical por 3 h e 30 minutos a 80 W (1500 V). A genotipagem das variedades de milho com o marcador RAPD amplificou 409 fragmentos com índice médio de polimorfismo de 81,9 %. O SSR gerou 134 fragmentos com 78,3 % de polimorfismo. Por outro lado, o AFLP amplificou 1889 fragmentos com índice médio de polimorfismo de apenas 40,3 %. Os fragmentos polimórficos foram submetidos às análises de similaridade genética através do coeficiente de Jaccard e de agrupamento pelo método UPGMA individualmente e conjuntamente para os marcadores. O coeficiente médio de similaridade foi de 57 % para o RAPD; 56 % para o SSR; 74 % para o AFLP e 69 % para a análise conjunta. Os dendogramas obtidos a partir do RAPD e SSR mostraram 8 grupos distintos, enquanto que o dendograma obtido a partir do AFLP e da análise conjunta formaram 6 e 7 grupos, respectivamente. De maneira geral, as correlações entre as matrizes de similaridade foram baixas, porém entre o AFLP e a análise conjunta foi de 96 %. Os resultados revelaram ampla variabilidade genética entre os acessos de milho crioulo. Os marcadores RAPD e SSR apresentaram os maiores índices médios de polimorfismo e o AFLP demonstrou maiores índices de similaridade genética entre os acessos crioulos. De maneira geral, os marcadores utilizados foram ferramentas eficientes para amostrar a diversidade genética e agrupar as variedades de acordo com os locais de coleta, embora possuam capacidade diferencial de revelar polimorfismo bem como para agrupar os acessos crioulos de milho.