caracterização in situ e estrutura genética de populações de Gossypium mustelinum

Gossypium mustelinum Miers ex Watt is the only cotton species native from Brazil. It is endemic of the semi-arid region from North-east of the country, where it occur near from resilient water sources. The threats to the in situ conservation of the populations are caused by human interference in its habitat, mainly by excessive cattle graze and deforestation. Establish efficient strategies of in situ conservation depend on the accomplishment of a diagnosis of how the specie is found in its natural environment, and the knowledge about the genetic structure of the populations. The objectives of this work were i) to determine the in situ conditions of two populations present in rivers from basin of Rio Paraguaçu at the Bahia State, ii) to evaluate the structure and genetic variability presented in both populations, iii) to establish in situ and ex situ conservation strategies. It were realized collection in november 2007, when was realized in situ characterization of G. mustelinum. SSR markers were used for analyze 218 genotypes deriving from two populations of the G. mustelinum, localized at Tocó river and the Capivara river. The allelic frequencies, the heterozigosity and the F statics were estimated. All the plants were classified as wild and natives, and there was no evidence of the use the plants or its parts. The populations showed different conservation conditions in situ. Few plantlets were found in sites with excessive cattle feed, an indication that the damages in young plants should be high enough to compromise the renovation of the populations. On the other hand, populations were well preserved when the anthropic damages was low or inexistent. The 14 SSR primer pairs amplified 17 loci with a medium number of 5 alleles per locus (a total of 85 alleles). The high level of endogamy estimated (FIS=0,808) and the low observed heterozygosity (H0=0,093) were indicatives that the populations reproduce mainly by selfing, geitonogamy and crosses between related individuals. The genetic diversity was high (HE=0,482) and the differentiation between the populations was very high (FST=0,328). At least two sites from both populations of G. mustelinum must be preserved to achieve suitable in situ conservation. Actions that preserve the gallery forest and keep the cattle away should implemented, and could be as simple as erecting a fence. It is not possible anticipated if the in situ preservation will be possible. Therefore collections and ex situ preservation of representative specimens are essential to conserve the genetic diversity of native G. mustelinum

Caracterização genética e in situ de Gossypium barbadense na região norte do Brasil

Brazil has been considered one of the diversity centers of Gossypium barbadense species. It is believed that a relatively big erosion genetic process occurs with the species, due to economic, cultural and agricultural problems. A local diagnostic about species situation is the first step for reducing the diversity loss and establishing conservation strategies in situ. This research aimed the identification of the presence of Gossypium populations, characterization, determination of the main risks and collection of the accesses to store in germoplam banks, in Para and Amapa States. Expeditions were conducted in November 2004. An interview was carried out with the plant proprietor for characterizing in situ of G. barbadense species and of the environment where the plants were inserted. On hundred seventy nine plants in 22 municipal districts were collected in Para State and 117 plants in nine municipal districts in Amapa State. The majority of plants belong to G. barbadense species (98% in Amapa and 94% in Para). Plants occur in back yards, beside roads and spontaneously. That ones from back yards were more abundant (97% in Amapa and 95% in Para) and maintained as medicinal plants as the principal reason. Plants in natural environments in both states evaluated were not found, therefore, the creation of reserves and the application of others conventional methods of maintenance in situ are not applicable. The plant proprietors do not use to store or process seeds. Seed storage was reported as a practice by only 1% of the plant proprietors from Para and 11% from Amapa. The most plants collected were from two to three years of age (58% in Amapa and 93% in Para). As conclusions G. barbadense is the species most spread in the two studied states and are found in back yards. In Amapa State the botanical variety barbadense or Quebradinho is predominant, whereas in Para State the predominant variety is brasiliense or Rim-de-boi. Adequate conservation of thestudied species must be carried out in germoplasm collections maintained ex situ

Variação genética em progênies de Myracrodruon urundeuva F.F. & M.F. Allemão em três sistemas de cultivo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genética e biologia reprodutiva de vriesea minarum (Bromeliaceae): em busca de estratégias de conservação no quadrilátero ferrífero, minas gerais

Vriesea minarum is a rupiculous bromeliad species, with naturally fragmented populations, restricted to the Iron Quadrangle, Minas Gerais, Brazil. It is a threatened species, which is suffering from habitat loss due to the growth of cities and mining activities. The knowledge of genetic variability in plant populations is one of the main branches of conservation genetics, linking genetic data to conservation strategies while the knowledge about plant reproductive biology can aid in understanding key aspects of their life story, as well as in the comprehension of their distribution and survival strategies. Thus, the study of diversity, richness, and genetic structure, as well as the reproductive biology of populations of V. minarum can contribute to the development of conservation actions. Chapter 1 presents the transferability of 14 microsatellite loci for V. minarum. Among the results of this chapter, we highlight the successful transferability of 10 microsatellite loci described for other species of Bromeliaceae, all of which are polymorphic. In Chapter 2, we present the genetic analyses of 12 populations of V. minarum that are distributed throughout the Iron Quadrangle. We used the 10 microsatellite loci tested in Chapter 1. The results show a low population structuring (Fst = 0.088), but with different values of genetic richness (mean = 2.566) and gene diversity (mean = 0.635) for all populations; and a high inbreeding coefficient (Gis = 0.376). These may be the result of pollinators action and/or efficient seed dispersal, thus allowing a high connectivity among populations of naturally fragmented outcrops. The reproductive biology and floral morphology of a population of V. minarum, located in the Parque Estadual da Serra do Rola-Moça, are studied in Chapter 3. This reserve is the only public environmental protection area where the species occurs. As a result of field experiments and observations, we found that the species has its flowering period from January to March, with flowers that last for two days and that it has a mixed pollination syndrome. It is primarily alogamous, but also has the capacity to be self-ferilized. It is expected that data obtained in chapters 1, 2 and 3 serve as basis for other studies with species from the ferruginous rocky fields, since until now, to our knowledge, there are no other survey of endemic species from the Iron Quadrangle, seeking to merge the genetic knowledge, with the data of the reproductive biology, with the ultimate aim of biodiversity conservation. Considering the great habitat loss for the species by mining, it becomes crucial to analyze the creation of new protected areas for its conservation

Caracterização genética e evolução dos vírus dengue no Estado do Rio Grande do Norte

Dengue is considered as the most important arthropod-borne viral disease throughout the world due to the high number of people at risk to be infected, mainly in tropical and subtropical regions of the planet. The etiologic agent is Dengue Virus (DENV), it is a single positive-stranded RNA virus of the family Flavivirus, genus Flaviviridae. Four serotypes are known, DENV-1, DENV-2, DENV-3 and DENV-4. One of the most important characteristic of these viruses is the genetic variability, which demands phylogenetic and evolutionary studies to understand key aspects like: epidemiology, virulence, migration patterns and antigenic characteristics. The objective of this study is the genetic characterization of dengue viruses circulating in the state of Rio Grande does Norte from January 2010 to December 2012. The complete E gene (1485 pb) of DENV1, 2 e 4 from Brazilian (Rio Grande do Norte) patients was sequenced. Phylogenetic analysis was performed using MEGA 5.2 software, Tamura-Nei model and Neighbor-Joining trees were inferred for the datasets. In Brazil, there is just one DENV-1 genotype (genotype V), one DENV-2 genotype (Asian/American) and two DENV-4 genotypes (genotypes I and II). Brazilian strains of DENV-1 are subdivided in two different lineages (BR-I and BR-II), the Brazilian strains of DENV-2 are subdivided in four lineages (BRI-IV) and genotype II of DENV-4 is subdivided in three Brazilian lineages (BRI-III). The viruses isolated in RN belong to lineage BR-II (DENV-1), BR-IV (DENV-2) and BR-III (DENV-4).The Caribbean and near Latin American countries are the main source of these viruses to Brazil. Amino acids substitutions were detected in three domains of E protein, this makes clear the necessity of studies that associate epidemiological and molecular data to better understand the effects of these mutations. This is the first study about genetic characterization and evolution of Dengue viruses in Rio Grande do Norte, Brazil

Análise da estrutura genética populacional da piraúna (cephalopholis fulva: serranidae) ao longo da costa e ilhas oceânicas brasileiras

Brazil has about 8,500 km of coastline and on this scale, fishing is a historically important source of animal protein for human consumption. The national fishing background shows a growth of marine fishery production until 1985 and within this period it was recorded a steady decline. From the year 2003 fishing statistics aim to some "recovery" of the total fisheries production, which probably is related to a change in industry practice. The target of commercial fishing became smaller species with low commercial value, but very abundants. The coney, Cephalopholis fulva (Serranidae), is one of these species that have been suffering a greater fishing pressure in recent years. In order to provide data about the current situation of the genetic diversity of these populations, several molecular markers have been being used for this purpose. The prior knowledge of genetic variability is crucial for management and biodiversity conservation. To this end, the control region sequences (dloop) of mtDNA from Cephalopholis fulva (Serranidae) from five geographical points of the coast of Brazil (Ceará, Rio Grande do Norte, Bahia and Espírito Santo) and the Archipelago of Fernando de Noronha (FN) were sequenced and their genetic diversity analyzed. The FST values were very low (0.0246 to 0.000), indicating high gene flow between the sampled spots. The indices h and indicate a secondary contact between previously allopatric lineages differentiated or large and stable populations with long evolutionary history. Tests of Tajima and Fu showed expansion for all populations. In contrast, the mismatch distribution and SSD indicated expansion just for coastal populations. Unlike other species of the Atlantic which have been deeply affected by events on later Pleistocene, the population-genetic patterns of C. fulva may be related to recent events occurred approximately 130,000 years ago. Moreover, the data presented by geographical samples of the specie C. fulva showed high genetic diversity, also indicating the absence of deleterious effects of over-exploitation on this specie, as well as evidence of complete panmixia between all sampled populations

Variabilidade isoenzimática em oito raças de milho

Com o objetivo de avaliar a variabilidade genética e as relações de afinidade entre dezenove populações de oito raças de milho (Zea mays L.) - as comerciais antigas Cateto Sulino, Cateto Sulino Grosso, Cateto Nortista e Canario de Ocho, e as raças indígenas Moroti, Lenha, Entrelaçado e Caingang - analisaram-se os seguintes sistemas enzimáticos: glutamato oxalacetato transaminase (GOT), esterase (EST) e malato desidrogenase (MDH). Observou-se maior semelhança entre as raças pertencentes a um mesmo grupo, mas as populações analisadas não se agruparam de acordo com as raças, classificadas anteriormente segundo caracteres morfológicos. Os sistemas enzimáticos utilizados não permitiram a caracterização individual de cada uma das raças analisadas. As indígenas apresentaram maior variabilidade do que as comerciais antigas quanto ao número de alelos por loco e à porcentagem de locos polimórficos.

Divergência genética entre acessos de Passiflora cincinnata mast com base em descritores morfoagronômicos

Este trabalho teve como finalidade estimar a divergência genética entre acessos de maracujazeiro (Passiflora cincinnata Mast.) conservados na coleção de trabalho da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Semi-Árido, em Petrolina-PE. O experimento foi conduzido em delineamento de blocos ao acaso, com quatro repetições. A avaliação foi realizada em 32 acessos, com base em 23 caracteres: dois relativos à planta, três às folhas, seis às flores, quatro aos frutos, quatro às sementes, dois às características químicas dos frutos e dois à produção. O comportamento dos acessos foi pesquisado pelas análises univariada e multivariada, com estimativas das dissimilaridades obtidas pela distância generalizada de Mahalanobis (D²) e formação do agrupamento pelo método de Tocher. Os acessos apresentaram variabilidade genética para todos os descritores utilizados na avaliação. As distâncias genéticas entre pares de acessos variaram de 17 a 598, com média 152. O acesso 18-D0542 foi indicado como o mais divergente e o mais produtivo, devendo compor programas de intercruzamentos e ser recomendado para cultivos experimentais por produtores. As características de maior importância para a divergência genética foram: a massa total dos frutos (42,29%), a viabilidade de pólen (8,62%) e a área foliar (7,16%). O agrupamento dos acessos não se correlaciona às Unidades Geoambientais originais de coleta.

Similaridade genética entre acessos de goiabeiras e araçazeiros baseada em marcadores moleculares AFLP

Espécies do gênero Psidium, como goiabeira e araçazeiros, são economicamente importantes e têm como área de diversidade genética primária o Brasil. Foram determinadas as relações genéticas, com base no marcador AFLP, para acessos do Banco Ativo de Germoplasma (BAG) de Psidium da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Semiárido, para orientar trabalhos de melhoramento e de manejo de recursos genéticos do gênero. Foram analisados 88 acessos, sendo 64 de goiabeira e 24 de araçazeiros, coletados em dez Estados brasileiros, adotando-se para agrupamento o dendrograma UPGMA, considerando a matriz de similaridade do coeficiente de Jaccard de 149 bandas polimórficas de AFLP de 16 combinações dos iniciadores EcoRI e MseI. A análise da variância de dados moleculares foi realizada considerando a variação entre e dentro das populações de goiabeira dos dez Estados. O dendrograma apresentou boa definição, com coeficiente de correlação cofenética de 0,94. Foram observados dois grandes grupos: um formado por acessos de goiabeira e outro com acessos de araçazeiros, com inclusão de alguns acessos de goiabeira. Foram observados agrupamentos específicos no dendograma apenas para os indivíduos de goiabeira coletados em Goiás e Roraima. Os acessos estudados apresentaram similaridade variando de 28 a 98%, evidenciando a alta variabilidade genética dos mesmos. A variação entre acessos foi estimada em 0,16 (ΦST), indicando diferenciação genética moderada entre as populações de goiabeira dos dez Estados. Para aumentar a variabilidade genética do BAG estudado, sugere-se a coleta de um número maior de acessos nos Estados de Goiás e Roraima, dado o alto índice de similaridade entre os acessos provenientes destes Estados, bem como coletas amplas em outros Estados brasileiros. Sugerem-se ainda cruzamentos entre os poucos acessos de goiabeira posicionados no grupo dos araçazeiros para o desenvolvimento de híbridos interespecificos no gênero Psidium.

Conservação genética de populações de Cryptocarya moschata Nees (Lauraceae) na Mata Atlântica do estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variabilidade entre genótipos de feijoeiro na eficiência no uso do fósforo

A utilização da variabilidade genética em feijoeiro (Phaseolus vulgaris L.) para eficiência na absorção e utilização de fósforo se mostra como uma alternativa para contornar a deficiência deste elemento em solos de cerrado. Para detectar tais eficiências, foi desenvolvido um experimento em casa de vegetação na Universidade Federal de Uberlândia-MG, entre julho e agosto de 1997. O delineamento experimental foi de blocos casualizados com quatro repetições, em esquema fatorial 8 x 2. Foram avaliados oito genótipos de feijoeiro (BAT 477, Carioca MG, Emgopa 201, Jalo Precoce, Pérola, Rosinha, Roxo e Xamego) e duas doses de P2O5 (24 e 120mg dm-3). Após 45 dias da germinação, foram analisadas a produção de matéria seca da parte aérea e das raízes dos genótipos; conteúdo de fósforo na parte aérea e das raízes; razão raiz:parte aérea e a eficiência no uso do fósforo (valor a), classificando-os em quatro grupos: eficientes e responsivos, não eficientes e responsivos, eficientes e não responsivos e não eficientes e não responsivos. Os genótipos classificados como eficientes na absorção e utilização de fósforo foram BAT 477, Jalo Precoce e Roxo, enquanto que os classificados como responsivos foram os genótipos Carioca MG, Jalo Precoce, Pérola e Roxo.

Genetic variability in natural populations of Zeyheria montana mart. from the Brazilian Cerrado

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Virulence profile of ten Paracoccidioides brasiliensis isolates: association with morphologic and genetic patterns

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Potencial de uso de gramíneas como substrato pasteurizado no cultivo do cogumelo Pleurotus ostreatus (Jacq.) P. Kumm

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise genética do tubarão-raposa Alopias superciliosus no Oceano Atlântico, utilizando região controle do DNA mitocondrial

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)