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A strategy for genetic improvement of coffee Coffea canephora plants is to aggregate through artificial crossings the characteristics of the Conilon botanical variety, such as shorter height and drought resistance, with the higher average grain size and resistance to pests and diseases of the Robusta variety. Efficiently separating the clones into these two groups with the aid of appropriate analytical procedures makes field tasks easier for professionals and, thus, allows the systematic production of intervarietal hybrids. This study verifies if the non-parametric discriminant analyzes of the k-nearest neighbors (k-NN) and k-average neighbors (k-AN) would be able to correctly classify 130 coffee clones in their botanical varieties previously designated as Conilon, Robusta and Intervarietal Hybrids populations from ten quantitative agronomic characteristics, including the processed coffee beans yield, considering the existing population genetic divergence. These characteristics were found to be good discriminatory variables and the discriminant analyzes k-NN and k-AN, based on the principle of similarity by neighborhood, classified the clones with high hit rates. The k-AN discriminant analysis was able to better discriminate intervarietal hybrids from the group clones Conilon. The results correctly reflected the genetic diversity between the botanical varieties and intervarietal hybrids of Coffea canephora, allowing us to conclude that these classification methods can assist breeders in the main task of discriminating Conilon from Robusta clones. Made available in DSpace on 2021-12-14T02:09:06Z (GMT). No. of bitstreams: 1 cpafro-18640.pdf: 492291 bytes, checksum: 9d24b63c74eb0c2c56426cfb41674d9d (MD5) Previous issue date: 2021

Malaltia de Chagas; Trypanosoma cruzi; Variabilitat genètica Chagas disease; Trypanosoma cruzi; Genetic variability Enfermedad de Chagas; Trypanosoma cruzi; Variabilidad genética Background: Trypanosoma cruzi has a high rate of biological and genetic variability, and its population structure is divided into seven distinct genetic groups (TcI-TcVI and Tcbat). Due to immigration, Chagas disease (ChD), caused by T. cruzi, has become a serious global health problem including in Europe. Therefore, the aim of this study was to evaluate the existence of genetic variability within discrete typing unit (DTU) TcV of T. cruzi in Bolivian patients with chronic ChD residing in Barcelona, Spain. Methods: The DNA was extracted from the peripheral blood of 27 patients infected with T. cruzi DTU TcV and the fragments of the genetic material were amplificated through the low stringency single primer-polymerase chain reaction (LSSP-PCR). The data generated after amplification were submitted to bioinformatics analysis. Results: Of the 27 patients evaluated in the study, 8/27 (29.6%) were male and 19/27 (70.4%) female, 17/27 (62.9%) were previously classified with the indeterminate clinical form of Chagas disease and 10/27 (37.1%) with Chagas cardiomyopathy. The LSSP-PCR detected 432 band fragments from 80 to 1,500 bp. The unweighted pair-group method analysis and principal coordinated analysis data demonstrated the existence of three distinct genetic groups with moderate-high rates of intraspecific genetic variability/diversity that had shared parasite's alleles in patients with the indeterminate and cardiomyopathy forms of ChD. Conclusions: This study demonstrated the existence of a moderate to high rate of intra-DTU TcV variability in T. cruzi. Certain alleles of the parasite were associated with the absence of clinical manifestations in patients harboring the indeterminate form of ChD. These results support the need to search for increasingly specific targets in the genome of T. cruzi to be correlated with its main biological properties and clinical features in patients with chronic ChD. This work was supported by São Paulo Research Foundation (FAPESP)- fapesp.br/en (Grant No. 2018/22093-4), São Paulo Research Foundation (FAPESP)- fapesp.br/en (Grant No. 2019/11943-0), São Paulo Research Foundation (FAPESP)- fapesp.br/en (Grant No. 2016/25403-9), and Universitat Autònoma de Barcelona, Vall d'Hebron University Hospital, PROSICS Barcelona, Spain.

Wild genetic resources and their ability to adapt to environmental change are critically important in light of the projected climate change, while constituting the foundation of agricultural sustainability. To address the expected negative effects of climate change on Robusta coffee trees (Coffea canephora), collecting missions were conducted to explore its current native distribution in Uganda over a broad climatic range. Wild material from seven forests could thus be collected. We used 19 microsatellite (SSR) markers to assess genetic diversity and structure of this material as well as material from twoex-situcollections and a feral population. The UgandanC.canephoradiversity was then positioned relative to the species’ global diversity structure. Twenty-two climatic variables were used to explore variations in climatic zones across the sampled forests. Overall, Uganda’s nativeC.canephoradiversity differs from other known genetic groups of this species. In northwestern (NW) Uganda, four distinct genetic clusters were distinguished being from Zoka, Budongo, Itwara and Kibale forests A large southern-central (SC) cluster included Malabigambo, Mabira, and Kalangala forest accessions, as well as feral and cultivated accessions, suggesting similarity in genetic origin and strong gene flow between wild and cultivated compartments. We also confirmed the introduction of Congolese varieties into the SC region where most Robusta coffee production takes place. Identified populations occurred in divergent environmental conditions and 12 environmental variables significantly explained 16.3% of the total allelic variation across populations. The substantial genetic variation within and between Ugandan populations with different climatic envelopes might contain adaptive diversity to cope with climate change. The accessions that we collected have substantially enriched the diversity hosted in the Ugandan collections and thus contribute toex situconservation of this vital genetic resource. However, there is an urgent need to develop strategies to enhance complementaryin-situconservation ofCoffea canephorain native forests in northwestern Uganda.

Integrative conjugative elements (ICEs) are widespread in many bacterial species, often carrying antibiotic resistance determinants. In the present work, we screened a collection of Proteus mirabilis clinical isolates for the presence of type 1 SXT/R391 ICEs. Among the 76 isolates analyzed, 5 of them carry such elements. The complete sequences of these elements were obtained. One of the isolates carried the CMY-2 beta-lactamase gene in a transposon and is nearly identical to the element ICEPmiJpn1 previously described in Japan, and later shown to be present in other parts of the world, indicating global spread of this element. Nevertheless, the Brazilian isolate carrying ICEPmiJpn1 is not clonally related to the other lineages carrying the same element around the world. The other ICEs identified in this work do not carry known antibiotic resistance markers and are diverse in variable gene content and size, suggesting that these elements may be responsible for the acquisition of other advantageous traits by bacteria. Some sequences carried by these elements in Brazilian strains were not previously found in other SXT/R391 variants.

RESUMO: Há séculos, populações de plantas vem sendo selecionadas a fim de se obter linhagens com maior desempenho agronômico. Para o sucesso da seleção, a variabilidade genética é essencial, sendo que dentro do gênero Passiflora há grande variabilidade inter e intraespecífica. Neste trabalho, objetivou-se avaliar as características físicas de frutos de genótipos elite de maracujazeiro-doce (Passiflora alata) para fins de seleção. Foram avaliadas a massa, diâmetros longitudinal e equatorial de frutos, espessura e coloração da casca e massa e volume de polpa com e sem sementes e rendimentos de polpa. As fontes de variação para análise de variância foram os frutos de oito genótipos elite, com três repetições, cujas médias foram comparadas pelo teste de Tukey a 1% de probabilidade. Foram realizadas ainda análises multivariadas e de correlação entre as características. Houve diferenças estatísticas entre os genótipos elite para a maioria das características avaliadas. O genótipo elite sete foi o que apresentou maior rendimento de polpa sem sementes, em relação ao fruto e maior massa de fruto. Análises de agrupamento e dispersão gráfica evidenciaram uma tendência de agrupamento dos genótipos elite com base no formato dos frutos. A população apresenta variabilidade genética, que permite novos ciclos de seleção para ganho em rendimento de polpa e massa dos frutos. ABSTRACT: Over several past centuries, specific plant populations have been carefully selected to filter strains with higher agronomic performance. Genetic variability is most essential for successful selection. The Passiflora genus offers great inter- and intra-specific variability. This study aimed to evaluate the physical characteristics of the genotypes of the elite passion fruit (Passiflora alata) for selection purpose. We considered the physical traits of fruit mass, longitudinal and equatorial diameters, peel thickness and color, and pulp mass and volume without and with seeds and pulp yield. The sources of variation for the analysis of variance included the fruits of 8 elite genotypes, with 3 replications, whose means were compared by Tukey?s test at 1% probability. We also performed multivariate analysis and correlation between these characteristics. Statistical differences were noted between elite genotypes for most of the tested traits. The elite 7 genotype presented with the highest seedless pulp yield in relation to the fruit and the largest fruit mass. Cluster analysis and graphic dispersion revealed a tendency for clustering of the elite genotypes based on their fruit shape. The tested population showed genetic variability, which allowed new selection cycles toward gaining pulp yield and fruit mass. Made available in DSpace on 2020-03-11T00:38:24Z (GMT). No. of bitstreams: 1 16784596cr5002e20181056.pdf: 1438374 bytes, checksum: 3893fb338571463b692289649b21e9c1 (MD5) Previous issue date: 2020 Título em português: Variabilidade genética de genótipos selecionados de Passiflora alata baseada em características físicas de frutos.

The Southwestern Region of the Brazilian Amazon is formed by forests dominated by bamboos. The genus Guadua is endemic to the Americas, and little is known about the genetic diversity and structure of species of this genus. This study aimed to evaluate the genetic diversity and structure of two native Guadua species in natural populations in the Southwestern region of the Brazilian Amazon. Therefore, the genetic diversity and structure of Guadua aff. chaparensis and Guadua aff. lynnclarkiae were evaluated with the use of microsatellite molecular markers (SSR). It was verified that the average genetic diversity for the populations studied was considered high (^He=0.5) compared to other species of bamboo. All populations had rare and private alleles, and none of them presented significant values of inbreeding. The populations were divergent (^GST = 0.46), resulting in a low apparent gene flow. The Bayesian analysis showed that among the 350 individuals analyzed, five groups (K=5) were formed, with little similarity among the groups (Populations), although two of them presented clonal individuals. According to the results obtained, it can be conclude that populations should be treated as having unique characteristics, mainly when accessed for management and for in situ and ex situ conservation studies. Made available in DSpace on 2020-12-04T09:06:19Z (GMT). No. of bitstreams: 1 27026.pdf: 3771445 bytes, checksum: 8da5966e2a8c2d3a67241737eca1dbfb (MD5) Previous issue date: 2020

Carioca is the most important edible dry bean (Phaseolus vulgaris L.) grown in Brazil. It represents the largest dry bean market class in the world. The seed coat of carioca beans will darken under adverse harvest conditions and with the increasing of storage time. In general, darkened seeds are associated with older seeds that suffer from prolonged cooking times. A relatively new 'slow darkening' trait is available in carioca that delays seed coat darkening under storage. However, its effect on cooking time is unknown. The objective of this work was to evaluate two induction methods of seed coat darkening and to examine the effect of slow darkening trait on cooking time after storage. Lines derived from four segregating populations resulting from crossings between cultivar BRSMG Madrepérola with slow seed coat darkening, and the parents BRS Estilo, BRS Cometa, BRS Notável and BRS Sublime with normal darkening were evaluated. An experiment inlcuding 220 lines, 55 per population and the five parents, in a 15x15 triple lattice was conducted in the winter growing season in Brasilia. Seed coat darkening and cooking time traits were evaluated. Two methods for inducing seed coat darkening were compared: an accelerated aging test using UV light for 72 hours, and an extended storage for 90 days under ambient conditions. The correlation between the induction methods ranged from 0.77 to 0.85 for the different populations indicating either method could be used to discriminate lines with normal versus slow darkening trait. The percentage of light-colored grain lines was identified by both induction methods of seed coat darkening ranged from 75 to 85.7% in the populations. The genetic correlation between seed coat darkening and cooking time varied from -0.06 to -0.48, indicating that in some populations there is no significant genetic correlation between seed coat darkening and cooking time. Thus, light colored grains are not indicative of low cooking time, when they are considered genotypes with genetic variation for the seed coat darkening. Made available in DSpace on 2020-02-12T18:11:11Z (GMT). No. of bitstreams: 1 CNPAF2020ajcs.pdf: 824973 bytes, checksum: 81944f3c39650313d59267258a3ed0cb (MD5) Previous issue date: 2020

Anthurium affine is an ornamental Brazilian native plant very appreciated due to its long-lasting durability. To explore the genetic diversity available, 21 A. affine half-sibling progeny were evaluated using morphoagronomic and molecular descriptors. The morphoagronomic descriptors used were: plant height, plant diameter, growth habit, leaf number, leaf blade length, leaf blade width, petiole length, petiole diameter, leaf margin undulation, general appearance; soil cover rate and Random Amplified Polymorphic DNA (RAPD) markers the molecular one. All the descriptors within the progeny showed variability and general appearance, leaf margin undulation and soil cover rate are the ones that most contribute to the plants divergence. From 45 RAPD primers tested, 19 presented clear polymorphic bands (42.2%). Those generated 200 molecular markers, 81 (40.5%) of them being polymorphic. The number of polymorphic bands per RAPD primer ranged from one (OPB10) to eight (OPW11) and polymorphism ranged from 16.6% (OPB10) to 70% (OPW05). Grouping analysis of morphoagronomic and molecular descriptors formed five and four groups respectively. The dendrograms showed differentiation between accessions although there was no association between morphoagronomic and molecular groupings. There is genetic divergence within the half-sibling progeny of A. affine plants evaluated, which opens up possibilities for increase variability. RESUMO Anthurium affine é uma planta ornamental nativa do Brasil sendo muito apreciada pela sua longa duração. Para investigar a divergência genética disponível, 21 progênies de meio-irmãos A. affine foram avaliados utilizando descritores morfoagronômicos e moleculares. Os descritores morfoagronômicos utilizados foram: altura da planta, diâmetro da planta, hábito de crescimento, número de folhas, comprimento da folha, largura da folha, comprimento do pecíolo, diâmetro do pecíolo, ondulação da margem foliar, aparência geral, taxa de cobertura do solo, e marcadores do tipo Polimorfismo de DNA Amplificado ao Acaso (RAPD). Todos os descritores dentro da progênie apresentaram variabilidade e os descritores aparência geral, ondulação da margem foliar e taxa de cobertura do solo foram os que mais contribuíram para a divergência entre as plantas. Dos 45 primers testados, 19 apresentaram inequívocas bandas polimórficas (42.2%). Estas geraram 200 marcas moleculares, sendo 81 (40.5%) polimórficas. O número de bandas polimórficas por primers variou de um (OPB10) a oito (OPW11) e o polimorfismo variou de 16.6% (OPB10) a 70% (OPW05). Análises de agrupamento dos descritores morfoagronômicos e moleculares formaram cinco e quarto grupos, respectivamente. Os dendrogramas apresentaram diferenciação entre os acessos embora não haja associação entre os agrupamentos dos descritores morfoagronômicos e moleculares. Existe divergência genética dentro da progênie de meios-irmãos de A. affine, o que abre possibilidades para aumento da variabilidade.

Mangalarga Marchador (MM) is the most numerous horse breed in Brazil. The aim of this study was to analyze the genetic structure of the MM horses population of Brazil based on pedigree analysis and identify factors that may affect its genetic variability. Pedigree data from 1906 to 2015 was used and the inbreeding and probability of gene origin parameters were obtained, considering the total population (TP, n = 514,282) and a reference population (RP, n = 172,508) from 2005 to 2015. The generation interval was 10.43 in the TP and 9.48 in the RP. The inbreeding coefficient (F) was 1.02% in the TP and 1.10% in the RP. The effective population size was 1,471 for the TP and 959 for the RP. The effective number of ancestors, founders, and founder genomes were 1,038, 1,062, and 150 in the TP, and 198, 225, and 133 in the RP, respectively. The numbers of founders that exhibit 50% of the current gene pool of the breed represented 7.94% of the total founders of the TP and 19.09% of the RP. The analysis of probability of gene origin alert for a small loss of genetic diversity in the recent population. However, the Mangalarga Marchador population does not exhibit relevant factors that may seriously affect your genetic variability and that would impair the evolution of the breed in Brazil.

The objective of this study was to assess the genetic diversity among accessions of Paspalum notatum based on morphological marker traits and identify those morphological traits that contribute most to the variability among accessions. Fifty-three accessions were evaluated for the following traits: length, width, color, and pubescence of sheath; length, width, insertion angle, color of midrib, and pubescence of leaves; number, length, and angle of racemes; length of flowering stems; and plant growth habit (erect or prostrate). Multivariate analysis of the quantitative morphological data based on the Mahalanobis distance and UPGMA method grouped the accessions into 19 heterogeneous clusters. The relative contribution of each trait to cluster formation was obtained using the Singh method. Qualitative morphological traits were used to construct a dendrogram based on Jaccard's similarity, generating 13 clusters. Based on the morphological traits investigated, there is high genetic variation among accessions of P. notatum, demonstrating that these accessions have a good potential for a breeding program. Length of racemes, width of sheath, length of flowering stems, and length of leaves were found to contribute most to the variability among accessions. A number of traits contributed to a lesser degree. The set of characters used are representative of the vast phenotypic plasticity observed in P. notatum, a diversity which is likely to be related to the species apomictic form of reproduction and the origin of the accessions.

Aims Fungal diseases are among the main factors limiting high yields of soybean crop. Colletotrichum isolates from soybean plants with anthracnose symptoms were studied from different regions and time periods in Brazil using molecular, morphological and pathogenic analyses. Methods and Results Bayesian phylogenetic inference of GAPDH, HIS3 and ITS-5.8S rDNA sequences, the morphologies of colony and conidia and inoculation tests on seeds and seedlings were performed. All isolates were clustered only with Colletotrichum truncatum species in three well-separated clusters. Intraspecific genetic diversity revealed 27 distinct haplotypes in 51 fungal isolates; some of which were identical to C. truncatum sequences from other regions around the world, while others were related to alternative hosts. Conidia were falcate, hyaline, unicellular and aseptate, with variable dimensions, formed in acervuli. Despite being pathogenic to seedlings by both inoculation methods, variation was observed in the aggressiveness of the tested isolates, which was not correlated to genetic variation. Conclusion The identification of C. truncatum in the sampled isolates evidenced it being the only causal agent of soybean anthracnose in Brazil until 2007, with relevant genetic, morphological and pathogenic variability as well as a broad geographical origin. The wide distribution of the predominant C. truncatum haplotype indicated the existence of a highly efficient mechanism of pathogen dispersal over long distances, reinforcing the role of seeds as the primary source of disease inoculum. Significance and Impact of the Study The characterization and distribution of Colletotrichum species in soybean-producing regions in Brazil is fundamental for understanding the disease epidemiology and for ensuring effective control strategies against anthracnose. This article is protected by copyright. All rights reserved.

Jatropha is a potential oilseed crop, which requires mitigating factors such as the low genetic variability of the species. The solution runs through the research of Brazilian germplasm. Attention should be given to the germplasm of jatropha the north of Minas Gerais, because this is the oldest national collection and because this region may be a regions of jatropha diversity due to selection pressure arising from environmental adversities. Therefore, the objective of this study was to investigate the genetic diversity of 48 accessions of collection from Empresa de Pesquisa Agropecuária de Minas Gerais (EPAMIG), using SSR and ISSR markers. The results showed low genetic diversity, but some individuals stood out as J. mollissima (48), J. podagrica (47), Mexican accessions (42, 43, 44 and 45) and some national accessions (28, 29, 41 and 46). Therefore, aiming to increase the genetic variability and improve the effectiveness of jatropha breeding programs, it is suggested to explore such as parental accessions to generate commercial hybrids. This fact implies the possibility to support future production of jatropha, since this culture may be an important source of income, especially for small farmers living in semiarid regions of Brazil.

High-risk human papillomavirus cervical infection is currently a well-established cause of cervical cancer. However, only a few women with persistent infections will develop cervical precancerous and malignant lesions. Approximately 20% of all cervical cancers are attributable to non-16/18 serotypes. This study aims to evaluate the results of our clinical approach to women with this infection.We conducted an observational and prospective study from September 2012 to September 2017, which included women with isolated non-16/18 high-risk human papillomavirus infection (with normal cytology). After re-evaluation, two groups were compared: women with spontaneous regression of the infection and women with persistent infection. Clinical and demographic data were analysed as well as the rate of progression to precancerous and malignant lesions.We included 165 women, of which 121 were re-evaluated with co-test at least one year later. After re-evaluation, 13.2% of women revealed precancerous lesions but only two (1.7%) of them presented high-grade squamous intraepithelial lesions. Sixty-seven women (55.4%) showed spontaneous regression of the infection and 54 women (44.6%) maintained it. Women with persistent infection developed more precancerous lesions (27.8%; p0.001) and high-grade squamous intraepithelial lesions (3.7%; p0.001). There was also an association between persistent infection and postmenopausal status.Human papillomavirus 16/18 cervical infection is associated with higher risk of cervical cancer when compared with other serotypes.Re-evaluation with co-test one year after the diagnosis of isolated non-16/18 human papillomavirus infection seems to be a reasonable approach.Introdução: O cancro cervical é causado pelo papiloma vírus humano de alto risco. No entanto, apenas algumas mulheres com infeções persistentes desenvolvem lesões pré-malignas e malignas. Aproximadamente 20% destas neoplasias são causadas por serotipos que não os 16 e 18. Este estudo surge com o objetivo de avaliar a nossa prática clínica neste âmbito. Material e Métodos: Realizámos um estudo observacional e prospetivo entre setembro de 2012 e setembro de 2017, com inclusão de mulheres com infeção cervical isolada com papiloma vírus humano de alto risco, excluindo os serotipos 16 e 18 (com citologia negativa). Após reavaliação, comparámos dois grupos: mulheres que apresentaram resolução espontânea da infeção e mulheres com infeção persistente. Foram analisados dados clínicos e demográficos bem como a taxa de progressão para lesões precursoras e malignas. Resultados: Incluímos 165 mulheres e reavaliámos com co-teste 121 delas com pelo menos um ano de intervalo. Após reavaliação, 13,2% desenvolveram lesões precursoras, mas apenas duas (1,7%) foram consideradas de alto grau. Sessenta e sete mulheres (55,4%) apresentaram resolução espontânea da infeção e 54 (44,6%) mantiveram-na. As mulheres com infeção persistente desenvolveram mais lesões precursoras (27,8%; p0,001) e de alto grau (3,7%; p0,001). Constatou-se uma associação entre a persistência da infeção e pós-menopausa. Discussão: A infecção cervical com serotipos 16/18 associa-se a uma maior risco de desenvolvimento de cancro cervical quando comparada com outros serotipos. Conclusão: A reavaliação com co-teste um ano após o diagnóstico de infecção cervical isolada com papiloma vírus humano de alto risco, excluindo os serotipos 16 e 18, parece ser uma abordagem adequada.

The peach palm (Bactris gasipaes) is a palm tree that produces palm heart originated of Amazonia with economic, social and environmental sustainability. To obtain improved cultivars it is necessary the evaluation and selection of genotypes with characteristics that support producers, manufacturing and consumers. In this context, the objective of this study was to estimate genetic parameters for palm heart production traits of peach palm considering half sibs progenies. Twenty progenies of Putumayo macrocarpa race were evaluated in seven cultivation cycles. The experiment was designed in complete randomized blocks, with 40 repetitions and one plant per plot. The genetic parameters were estimated by REML/BLUP methodology. Low genetic variability was observed in the population, possibly due to the narrow genetic base from original population. However, considering the significant genetic effect and the progeny mean heritability, the selection performed between progenies is more efficient than individual selection. The high number of measurements required for most of the evaluated characters becomes impractical in peach palm breeding programs. The number of palm heart per plant can be used to perform indirect selection for total production of palm heart. A pupunheira (Bactris gasipaes) é uma palmeira produtora de palmito oriunda da Amazônia, que apresenta sustentabilidade econômica, social e ambiental. Para a obtenção de cultivares melhoradas é necessário a avaliação e seleção de genótipos com características que atendam produtores, processadores e consumidores. Assim, o objetivo deste trabalho foi estimar parâmetros genéticos para os caracteres de produção de palmito de pupunha considerando progênies de meio-irmãos. Foram avaliadas 20 progênies da raça macrocarpa Putumayo em sete ciclos de cultivo. O experimento foi delineado em blocos completos ao acaso, com 40 repetições e uma planta por parcela. Os parâmetros genéticos foram estimados segundo metodologia REML/BLUP. Baixa variabilidade foi observada na população de estudo, possivelmente devido à estreita base genética da população original. Contudo, considerando o efeito genético significativo e as herdabilidades médias de progênie, a seleção praticada entre progênies é mais eficiente que a seleção individual. O grande número de medições necessárias para a maioria dos caracteres avaliados torna-se impraticável em programas de melhoramento de pupunheira. O número de palmitos por planta pode ser utilizado na seleção indireta para produção total de palmito. Made available in DSpace on 2019-07-11T00:47:50Z (GMT). No. of bitstreams: 1 26815.pdf: 970523 bytes, checksum: 4fd87650d4a084a54840f584638deeb5 (MD5) Previous issue date: 2019

The cajuí Anacardium spp., which is similar to the caju Anacardium Ocidentale L., is a species adapted to edaphic-climatic conditions of the biome Cerratinga (Cerrado e Caatinga). Its fruit is composed of one swollen stalk (pedicel) which is formed by nutritional reserves rich in vitamin C and drupe (cashew nut). It is also rich in protein and lipids, but with smaller size. This paper focuses on investigating the applicability of the biplot graphical analysis in the process of selective breeding of cajuí population. The cajuí working population in Embrapa Meio Norte comprises of 11 genotypes collected in areas of natural habitat in the state of Piaui. The experiment was designed in randomized complete blocks with two plants per plot and four replications. A graphical analysis (biplot) was used to study the relationships between variables and behavior of the experimental genotypes. This was implemented to principal component analysis based on singular value decomposition biplot. The total variable weight can be predicted from length of peduncle, basal and apical diameter of peduncle, and variables of easy mensuration. Genotypes M40A, M23, M14, and M17 are similar to each other and they have high amounts of brown, apical and basal diameter of the peduncle, total weight, and peduncle length. They are considered as candidates selected for consumption in natura and industrial processing. The graphical analysis (biplot) showed robustness in the presentation of relationships between variables considered and the indication of the selection candidate genotypes in the population studied. Made available in DSpace on 2019-12-09T18:16:59Z (GMT). No. of bitstreams: 1 ART19049.pdf: 486166 bytes, checksum: 2f2a75b10f93ffaf655e6decb28e7e58 (MD5) Previous issue date: 2019

The search for alternatives to increase productivity and sustainability of livestock production in the Amazon region without increasing deforestation is challenging. Mixed pastures of grasses with forage peanut (Arachis pintoi) have shown positive economic impacts. However, gaps in the knowledge of the reproductive biology of A. pintoi have limited the development of new cultivars adapted to the environmental variations in the Brazilian Amazon. Pasture consortiums of Brachiaria humidicola with forage peanuts (cv. Mandobi) resulted in a 42% increase in weight gain productivity. New cultivars better adapted to the Amazon climate should bring even greater gains. We evaluated the mating system in twenty A. pintoi accessions, and approximately 40 offspring per accession genotyped with eight microsatellites (or markers). The parameters of genetic diversity and inbreeding, the outcrossing rate and coancestry were calculated. The observed heterozygosity was significantly higher and the fixation index was significantly lower in adults compared with the offspring. The crossing rate was variable among genotypes (2 to 80%), and the mean outcrossing rate was 36%. These results indicate that pollinator presence in pastures can influence gene flow in A. pintoi more than expected. Arachis pintoi presented a mixed mating system with a predominance of selfing, and families presented inbreeding and different levels of relatedness. New strategies of genotype conservation are needed to avoid pollinator-mediated crossing between accessions. A busca por alternativas para aumentar a produtividade e a sustentabilidade da pecuária na região Amazônica sem aumentar o desmatamento é desafiadora. Pastagens consorciadas de gramíneas com amendoim forrageiro (Arachis pintoi) têm mostrado impactos econômicos positivos. Porém, lacunas no conhecimento da biologia reprodutiva do amendoim forrageiro tem limitado o desenvolvimento de novas cultivares adaptadas as variações ambientais na Amazônia brasileira. Pastos consorciados de Brachiaria humidicola com amendoim forrageiro (cv. Mandobi) apresentaram cerca de 42% de aumento na produtividade do ganho de peso. Novas cultivares mais adaptadas ao clima amazônico, poderão trazer ganhos ainda maiores. O objetivo desse estudo foi avaliar o sistema reprodutivo em vinte acessos de A. pintoi e aproximadamente 40 progênies por acesso, genotipadas com oito microssatélites (ou marcadores). Os parâmetros de diversidade genética e endogamia, taxa de cruzamento e coancestria foram calculados. A heterozigosidade observada foi significativamente maior e o índice de fixação foi significativamente menor nos adultos comparado às progênies. A taxa de cruzamento foi variável entre os genótipos (2 a 80%) e a média da taxa de cruzamento foi 36%. Esses resultados indicam que a presença de polinizadores em pastagens pode influenciar o fluxo gênico em A. pintoi mais do que o esperado. Arachis pintoi apresentou um sistema de cruzamento misto com predominância de autofecundação e as famílias apresentaram endogamia e diferentes níveis de parentesco. Novas estratégias de conservação de genótipos são necessárias para evitar polinizadores mediadores de cruzamento entre os acessos. Made available in DSpace on 2019-11-06T18:09:20Z (GMT). No. of bitstreams: 1 26897.pdf: 214750 bytes, checksum: 955aa8b15739eeb5195664af46e1b0d2 (MD5) Previous issue date: 2019

Grass from the genus Brachiaria spp. predominates in pastures with low fertile soils. This scenario highlights the importance of the association with microorganisms to foster plant growth, which becomes essential to the successful establishment of this forage in such environments. This study aimed to evaluate the genetic variability and identify the mechanisms of plant growth promotion, in vitro, of bacteria associated with Brachiaria decumbens Stapf. and Brachiaria humidicola (Rendle.) Schweickerdt in Pernambuco, Brazil. We evaluated 20 isolates of diazotrophic bacteria obtained from the endophyte or rhizosphere communities. The genetic characteristics were determined via sequencing the 16S rRNA region, which allowed us to identify ten different bacterial genera: Bacillus sp., Burkholderia sp., Enterobacter sp., Klebsiella sp., Microbacterium sp., Pantoea sp., Ralstonia sp., Rhizobium sp., Sinomonas sp., and Sphingomonas sp., with a specificity of the genus Rhizobium sp. to Brachiaria decumbens Stapf.. The phenotypic and functional characteristics revealed that 100% of the bacterial strains produced indol-3-acetic acid (IAA) with the addition of L-tryptophan, and 60% presented IAA production independent of the L-tryptophan pathway. We also detected that 70% of the isolated bacteria possessed the capacity to solubilize phosphorus. The analysis of the enzymatic output revealed that 30% of the bacterial isolates produced cellulase, 60% produced pectate lyase, 15% produced polygalacturonase, and 30% produced amylase. We also detected the production of N-acyl homoserine lactones in 65% of bacterial strains. In summary, our results showed that plants of B. decumbens Stapf. and B. humidicola (Rendle.) Schweickerdt interacted with different bacterial genera capable of promoting plant growth.

Ceratocystis fimbriata Ellis & Halsted recently was recorded causing seed and seedling blight on Carapa guianensis Aubl. (andiroba), a tree species native to the Amazon Rainforest and prized for its valuable timber and medicinal seed oil. C. fimbriata more commonly causes wilt type diseases in woody hosts, especially on non-native host trees. However, on andiroba the disease occurs on seedlings and seeds, affecting the species regeneration. We studied 73 isolates of C. fimbriata on andiroba from three regions of the Amazon Basin to see if they represented natural or introduced populations. Analysis of ITS rDNA sequences and phylogenetic analysis of mating type genes revealed new haplotypes of C. fimbriata from the Latin American Clade that were closely related to other Brazilian populations of the fungus. In mating experiments, andiroba isolates were inter-fertile with tester strains of C. fimbriata from Brazil and elsewhere, confirming that they belong to a single biological species. Using microsatellite markers, 14 genotypes and populations with intermediate levels of genetic variability were found, suggesting that the fungus is indigenous to the Amazon Basin. Inoculation tests indicated that the andiroba isolates are host-specialized on andiroba, supporting the proposition of the special form C. fimbriata f. sp. carapa. Made available in DSpace on 2019-03-20T00:43:38Z (GMT). No. of bitstreams: 1 26788.pdf: 3260751 bytes, checksum: e216b037faec9a95d9551042e8f53907 (MD5) Previous issue date: 2019

Pollen and seed dispersal patterns greatly influence the spatial distribution of plant genetic diversity. Microsatellite-based parentage analysis provides accurate estimates of contemporary gene dispersal. Although most tropical trees have been shown to exhibit widespread pollen dispersal, few studies have estimated contemporary gene dispersal after seedling establishment. Bertholletia excelsa (Lecythidaceae) is pollinated by large-bodied bees, while previous seed-tracking experiments suggest their seeds are mainly dispersed across very short distances by scatter-hoarding rodents, who primarily act as seed predators. Here we used parentage analysis to provide contemporary estimates of pollen and seed dispersal in B. excelsa recruits. We examined six 25-ha plots located in two natural stands in the Acre River valley, in the southwestern Brazilian Amazon. We used 11 microsatellite markers to estimate genetic diversity and fixation index parameters in adults, seedlings and saplings. Genetic diversity was moderate and did not differ across size classes or sampling locations. We assigned pollen and seed parents for

Made available in DSpace on 2018-11-26T17:54:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-07-03 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Among rubber tree species, which belong to the Hevea genus of the Euphorbiaceae family, Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg. is the main commercial source of natural rubber production worldwide. Knowledge of the population structure and linkage disequilibrium (LD) of this species is essential for the efficient organization and exploitation of genetic resources. Here, we obtained single-nucleotide polymorphisms (SNPs) using a genotyping-by-sequencing (GBS) approach and then employed the SNPs for the following objectives: (i) to identify the positions of SNPs on a genetic map of a segregating mapping population, (ii) to evaluate the population structure of a germplasm collection, and (iii) to detect patterns of LD decay among chromosomes for future genetic association studies in rubber tree. A total of 626 genotypes, including both germplasm accessions (368) and individuals from a genetic mapping population (254), were genotyped. A total of 77,660 and 21,283 SNPs were detected by GBS in the germplasm and mapping populations, respectively. The mapping population, which was previously mapped, was constructed with 1,062 markers, among which only 576 SNPs came from GBS, reducing the average interval between two adjacent markers to 4.4 cM. SNPs from GBS genotyping were used for the analysis of genetic structure and LD estimation in the germplasm accessions. Two groups, which largely corresponded to the cultivated and wild populations, were detected using STRUCTURE and via principal coordinate analysis. LD analysis, also using the mapped SNPs, revealed that non-random associations varied along chromosomes, with regions of high LD interspersed with regions of low LD. Considering the length of the genetic map (4,693 cM) and the mean LD (0.49 for cultivated and 0.02 for wild populations), a large number of evenly spaced SNPs would be needed to perform genome-wide association studies in rubber tree, and the wilder the genotypes used, the more difficult the mapping saturation. Univ Estadual Campinas, Ctr Mol Biol, Campinas, SP, Brazil Univ Estadual Campinas, Genet Engn Ctr, Campinas, SP, Brazil Univ Sao Paulo, Escola Super Agr Luiz de Queiroz, Dept Genet, Piracicaba, Brazil FTS Sementes SA, Res & Dev Ctr, Ponta Grossa, Brazil Natl Inst Agr Bot, John Bingham Lab, Cambridge, England Agron Inst Campinas, Ctr Rubber Tree & Agroforestry Syst, Votuporanga, Brazil Empresa Brazileira Pesquisa Agr, Embrapa Cerrados, Cpac, Planaltina, Brazil Univ Estadual Paulista, Facu Engn Ilha Solteira, Dept Fitotecnia, Ilha Solteira, Brazil Ctr Cooperat Int Rech Agron Dev, UMR AGAP, Montpellier, France Univ Estadual Campinas, Dept Plant Biol, Biol Inst, Campinas, SP, Brazil Univ Estadual Paulista, Facu Engn Ilha Solteira, Dept Fitotecnia, Ilha Solteira, Brazil FAPESP: 2007/50392-1 FAPESP: 2012/50491-8 FAPESP: 2011/50188-0 FAPESP: 2014/18755-0 FAPESP: 2009/52975-0 FAPESP: 2014/11807-5 FAPESP: 2017/07908-9 FAPESP: 2012/05473-1 CNPq: 478701/2012-8 CNPq: 402954/2012-2

Made available in DSpace on 2015-10-22T06:22:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01. Added 1 bitstream(s) on 2015-10-22T09:46:16Z : No. of bitstreams: 1 S0100-83582015000100093.pdf: 662911 bytes, checksum: 94f6f13fc76838754a5b13de407561f7 (MD5) Objetivou-se neste trabalho estudar o controle de diferentes populações de Digitaria insularis pelo herbicida glyphosate, isolado e em mistura, além da combinação de métodos (químico e mecânico) no manejo de plantas adultas resistentes. Três experimentos foram desenvolvidos: um em vasos mantidos em condição ambiente e dois em condição de campo. No experimento em vasos, 12 populações de D. insularis foram pulverizadas com glyphosate isolado (1,44 e 2,16 kg e.a. ha-1) e em mistura (1,44 e 2,16 kg e.a. ha-1) com quizalofop-p-tefuryl (0,12 kg i.a. ha-1). O tratamento de 1,44 kg e.a. ha-1 de glyphosate mais 0,12 kg i.a. ha-1 de quizalofop foi suficiente para o controle adequado (>95%) de todas as populações. A população 11 (área de produção de grãos em Itumbiara - GO) foi considerada sensível ao glyphosate, e as demais, medianamente sensíveis ou tolerantes ao herbicida. Em campo, as plantas de D. insularis de um dos experimentos foram roçadas e, no outro, não. Oito tratamentos com herbicidas [glyphosate isolado (1,44 e 2,16 kg e.a. ha-1)e em mistura (1,44 e 2,16 kg e.a. ha-1) com quizalofop-p-tefuryl a 0,12 kg i.a. ha-1, clethodim a 0,108 kg i.a. ha-1 ou nicosulfuron a 0,06 kg i.a. ha-1] foram avaliados, combinados com ou sem a aplicação sequencial de tratamento padrão, pulverizado 15 dias após a primeira a aplicação. A combinação do controle mecânico com a aplicação de glyphosate (2,16 e 1,44 kg e.a. ha-1) mais quizalofop-p-tefuryl (0,12 kg i.a. ha-1) ou clethodim (0,108 kg i.a. ha-1), associados à aplicação sequencial, foi a estratégia mais eficaz para o manejo de plantas adultas de D. insularis resistentes. This study aimed to control different populations of Digitaria insularis by glyphosate herbicide, isolated and mixed, besides the combination of methods (chemical and mechanical) to manage resistant adult plants. Three experiments were conducted, one in pots which were maintained under non-controlled conditions and two under field conditions. In the experiment in pots, twelve populations of D. insularis were sprayed with isolated glyphosate (1.44 and 2.16 kg a.e. ha(-1)) and mixed (1.44 and 2.16 kg a.e. ha(-1)) with quizalofop-p tefuryl (0.12 kg i.a. ha(-1)). The treatment of 1.44 kg a.e. ha(-1) of glyphosate plus 0.12 kg a.i. ha(-1) of quizalofop was sufficient for adequate control (>95%) of all populations. Population 11 (area of grain production in Itumbiara, GO) was considered sensitive to glyphosate. Others populations were moderately sensitive or tolerant to the herbicide. In the field, the plants of D. insularis of one of the experiments were mowed and, in the other, there were not. Eight treatments with herbicides [isolated glyphosate (1.44 and 2.16 kg a.e. ha(-1)) and mixed (1.44 and 2.16 kg a.e. ha(-1)) with quizalofop-p-tefuryl at 0.12 kg a.i. ha(-1)), clethodim at 0.108 kg a.i. ha(-1)) or nicosulfuron at 0.06 kg a.i. ha(-1))] were assessed, in combination with or without sequential application of the standard treatment, sprayed 15 days after the first application. The combination of the mechanic control with the application of glyphosate (2.16 and 1.44 kg a.e. ha(-1)) plus quizalofop-p-tefuryl (0.12 kg a.i. ha(-1)) or clethodim (0.108 kg a.i. ha(-1)), associated to the sequential application, was the most effective strategy for the management of adult plants of resistant D. insularis. Embrapa Hortalicas, Brasilia, DF, Brazil UNESP, Sao Jose Do Rio Preto, SP, Brazil UNESP, Sao Jose Do Rio Preto, SP, Brazil

This study was realized to determine the genetic variation of Central Javanese duck based on the D-Loop mtDNA gene. D-loop gene was amplified using PCR technique by specific primer and sequenced using dideoxy termination method with ABI automatic sequencer. ClustalW from MEGA-6.06 software program was employed for multiple alignments of nucleotide sequences. Nucleotide sequences of D-loop gene of mtDMA from the Central Javanese duck were aligned together with other Anas isolates from Genbank using ClustalW of MEGA-6.06 program. The estimation of genetic distance and phylogenetic tree construction were analyzed by Neighbor-Joining method, whereas the calculation of distance matrix was performed using Kimura 2-parameter. Multiple alignments obtained were 720 nucleotides at position 56 to 779 at the 5 'end. The results of the polymorphism analysis on D-loop sequences produced 23 haplotypes. However, this haplotype information does not represent the relationship among the geographical origins of duck with the certain duck species name. Moreover, a total number of 32 variable sites were identified. Insertions were detected in four sequences (126, 155, 771 and 779 nucleotide number). In the phylogenetic analysis, it is safe to conclude that the Central Javanese duck is closely related to Anas platyrhynchos and Anas zonorynchos. RESUMO. Este estudo foi realizado para determinar a variação genética do pato de Java Central baseado no D-Loop mtDNA. A D-Loop foi amplificada utilizando a técnica de PCR com primer específico e sequenciado usando o método de terminação dideoxi com sequenciador ITB automático. ClustalW do programa software de MEGA-6.06 foi utilizado para alinhamentos de algumas sequências de nucleótidos. Sequências de nucleótidos de D-loop gene da mtDMA do pato de Java Central foram alinhados em conjunto com alguns isolados de Anas que foram obtidos de Genbank utilizando o programa ClustalW do programa MEGA-6.06. A estimativa da distância genética e a estrutura da árvore filogenética foram analisadas com o método Neighbor-Joining, enquanto que o cálculo da matriz de distância foi utilizado o parâmetro-2 Kimura. Os alinhamentos múltiplos obtidos foram 720 nucleótideos na posição 56 a 779 na extremidade 5’. As análises do polimorfismo sequencial do D-loop resultaram em 23 haplótipos. No entanto, esta informação haplótipo não representa a relação entre a origem geográfica de pato com o nome de determinadas espécies do pato. Além disso, num total de 32 sites favoráveis foram identificados. As inserções foram detectadas em quatro sequências (126, 155, 771 e 779 números de nucleotídeos). Na análise filogenética é seguro concluir que o pato de Java Central está estreitamente relacionada com a Anas platyrhynchos e Anas zonorynchos.

Southern Brazil encompasses areas with a subtropical climate, with significant number of frosts, which challenge or even impair growing tropical eucalypts. Eucalyptus benthamii and E. smithii rise as alternative species of subtropical origin with considerable frost-tolerance. Here we accessed the genetic variation for diameter at breast height (DBH), height (H), volume (VOL), bifurcation and straightness of four provenances of E. smithii and two of E. benthamii, cultivated in randomized block design in a farm in Rio Negrinho, Santa Catarina, southern Brazil. We found considerable genetic variability for the traits, all directly associated with the selection for wood production and quality. In general, most of the genetic variability was found within the provenances (Q d ranged from 63.6 to 73.1%), except for straightness (Q d = 13.5% and Q st = 81.9%). Although predicting genetic gains with provenance trials might have some drawbacks, the application of the REML/BLUP method was able to predict genetic gains for the growth variables DBH, H and VOL for provenances of the two species. The highest genetic gains were predicted for a provenance of E. smithii originated from Australia (13% for DBH, 5% for H and 6.1% for VOL). However, the genetic gains from a E. benthamii provenance from Santa Catarina state were not negligible (1.2% for DBH, 1.8 for H and 2.2% for VOL). Our results provide insights for further progeny trials aimed at investigating additive genetic variance and their components, which could improve the genetic control of the traits and assist breeding programs of E. smithii and E. benthamii. RESUMO O Sul do Brasil apresenta áreas com clima subtropical, com número significativo de geadas, que dificultam ou, até mesmo, impossibilitam o crescimento de eucaliptos tropicais. Eucalyptus benthamii e E. smithii surgem como espécies alternativas de origem subtropical com considerável tolerância a geadas. Estudou-se a variação genética para diâmetro a altura do peito (DAP), altura (H), volume (VOL) e tortuosidade em quatro procedências de Eucalyptus smithii e duas de E. benthamii, plantadas em delineamento em blocos casualizados em área experimental do município de Rio Negrinho, Santa Catarina, sul do Brasil. Foi encontrada variabilidade genética considerável para os caracteres investigados, todos diretamente associados com a seleção para produção e qualidade da madeira. Em geral, a maior proporção da diversidade genética foi encontrada dentro das procedências (Q d variou de 63,6 a 73,%), exceto para tortuosidade (Q d = 13,5% e Q st = 81,9%). Embora a predição de ganhos genéticos com testes de procedências apresente limitações, o emprego do método REML/BLUP permitiu predizer ganhos genéticos para as variáveis DAP, H e VOL nas procedências e indivíduos das duas espécies. Os ganhos genéticos mais elevados foram preditos para uma procedência de E. smithii originária da Austrália (13% para DAP, 5 % para H e 6,1% para VOL). Contudo, os ganhos genéticos potenciais com a procedência de E. benthamii de Santa Catarina não foram negligenciáveis (1,2% para DAP, 1,8% para H e 2,2% para VOL). Estes resultados representam importantes contribuições para a realização de testes de progênies posteriores para investigar a variação genética aditiva e seus componentes, o que pode aprimorar o conhecimento do controle genético dos caracteres e auxiliar no desenvolvimento de programas de melhoramento genético de E. smithii e E. benthamii.

Background Plasmodium vivax parasites are the predominant cause of malaria infections in the Brazilian Amazon. Infected individuals are treated with primaquine, which can induce haemolytic anaemia in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals and may lead to severe and fatal complications. This X-linked disorder is distributed globally and is caused by allelic variants with a geographical distribution that closely reflects populations exposed historically to endemic malaria. In Brazil, few studies have reported the frequency of G6PD deficiency (G6PDd) present in malaria-endemic areas. This is particularly important, as G6PDd screening is not currently performed before primaquine treatment. The aim of this study was to determine the prevalence of G6PDd in the region of Alto do Juruá, in the Western Brazilian Amazon, an area characterized by a high prevalence of P. vivax infection. Methods Five-hundred and sixteen male volunteers were screened for G6PDd using the fluorescence spot test (Beutler test) and CareStart™ G6PD Biosensor system. Demographic and clinical-epidemiological data were acquired through an individual interview. To assess the genetic basis of G6PDd, 24 SNPs were genotyped using the Kompetitive Allele Specific PCR assay. Results Twenty-three (4.5%) individuals were G6PDd. No association was found between G6PDd and the number of malaria cases. An increased risk of reported haemolysis symptoms and blood transfusions was evident among the G6PDd individuals. Twenty-two individuals had the G6PDd A(−) variant and one the G6PD A(+) variant. The Mediterranean variant was not present. Apart from one polymorphism, almost all SNPs were monomorphic or with low frequencies (0–0.04%). No differences were detected among ethnic groups. Conclusions The data indicates that ~1/23 males from the Alto do Juruá could be G6PD deficient and at risk of haemolytic anaemia if treated with primaquine. G6PD A(−) is the most frequent deficiency allele in this population. These results concur with reported G6PDd in other regions in Brazil. Routine G6PDd screening to personalize primaquine administration should be considered, particularly as complete treatment of patients with vivax malaria using chloroquine and primaquine, is crucial for malaria elimination. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1889-6) contains supplementary material, which is available to authorized users.

This study aimed to determine the variability and expression of the components of seed yield in twenty-three apomictic Paspalum plicatulum × Paspalum lepton hybrids and two male parent plants (P. lepton). We used a randomized block design with genotypes individually arranged into ten blocks. The variables were: number of total tillers/plant, number of vegetative tillers/plant, number of reproductive tillers/plant, percentage of reproductive tillers, number of racemes/inflorescence, number of seeds/inflorescence, weight of a thousand seeds, and seed yield. We assessed genetic variability using multivariate procedures: generalized Mahalanobis distance, Tocher's clustering optimization method, and quantification of the relative contribution of the variables. The quantification of variability, based on the components of seed yield of Paspalum plicatulum × Paspalum lepton hybrids, allows the formation of six groups of genotypes using Tocher's method, with high means for the characteristics studied. Weight of a thousand seeds and number of seeds/inflorescence were the traits that most contributed to the genetic dissimilarity. Genetic crosses involving genotype 10E5052 from group VI and 10E4071 from group V could be undertaken to isolate high yielding segregants, since these genotypes have high seed yielding potential.

The Meliponini, also known as stingless bees, are distributed in tropical and subtropical areas of the world and plays an essential role in pollinating many wild plants and crops These bees can build nests in cavities of trees or walls, underground or in associations with ants or termites; interestingly, these nests are sometimes found in aggregations. In order to assess the genetic diversity and structure in aggregates of Nannotrigona testaceicornis (Lepeletier), samples of this species were collected from six aggregations and genetically analyzed for eight specific microsatellite loci. We observed in this analysis that the mean genetic diversity value among aggregations was 0.354, and the mean expected and observed heterozygosity values was 0.414 and 0.283, respectively. The statistically significant Fis value indicated an observed heterozygosity lower than the expected heterozygosity in all loci studied resulting in high homozygosis level in these populations. In addition, the low number of private alleles observed reinforces the absence of structuring that is seen in the aggregates. These results can provide relevant information about genetic diversity in aggregations of N. testaceicornis and contribute to the management and conservation of these bees' species that are critical for the pollination process.

The selection of salinity tolerant bacteria may provide greater promotion of plant growth in soils with salt stress. This study aimed to isolate and select bacterial isolates of sugarcane, tolerant to salinity and plant growth promoters, and assess genetic diversity. To do so, endophytic root and rhizosphere of sugarcane, were isolated in culture medium with and without NaCl. The bacterial population density, the potential for biological nitrogen fixation (BNF), production of indole acetic acid (IAA), inorganic phosphate solubilization and quorum sensing molecule production were evaluated. Furthermore, the genetic diversity was assessed by Denaturing Gradient Gel Electrophoresis (DGGE) of nifH. Salinity tolerance tests were also conducted. There was no statistical difference in population density. As for the potential for BNF, IAA production, phosphate solubilization and quorum sensing molecule production, there was a high percentage of positive isolates. In the technique of DGGE nifH, the dendrogram showed high genetic variability. So there was the selection of bacteria that can contribute to the better development of sugarcane in saline soils. RESUMO A seleção de bactérias tolerantes a salinidade poderá propiciar maior promoção de crescimento vegetal em solos com estresse salino. Objetivou-se isolar e selecionar isolados bacterianos de cana-de-açúcar, tolerantes à salinidade e promotores de crescimento vegetal, e avaliar a diversidade genética. Para tanto, bactérias endofíticas de raiz e rizosfera, de cana-de-açúcar, foram isoladas, em meio de cultura com e sem NaCl. Avaliou-se a densidade populacional bacteriana, o potencial para a fixação biológica de nitrogênio (FBN), produção de ácido indol acético (AIA), solubilização de fosfato inorgânico e produção da molécula quorum sensing. Além disso, a diversidade genética foi avaliada pela técnica da Eletroforese em Gradiente de Gel Desnaturante (DGGE) do NifH. Testes de tolerância à salinidade também foram realizados. Não houve diferença estatística na densidade populacional. Quanto a FBN, produção de AIA, solubilização de fosfato e produção da molécula quorum sensing, houve alto percentual de isolados positivos. Na técnica do DGGE do gene nifH, o dendrograma indicou alta variabilidade genética. Portanto, houve a seleção de bactérias que possam contribuir para o melhor desenvolvimento da cana-de-açúcar em solos salinos.

International audience; The broadly distributed Neotropical stingless bee Tetragonisca angustula was once regarded as having two subspecies, T. angustula angustula and T. angustula fiebrigi. In a recent taxonomic revision, these subspecies were elevated to species status (T. angustula and Tetragonisca fiebrigi) based on morphology and distribution. While molecular studies show two well-delineated subgroups within the Tetragonisca, they are inconclusive as to whether there is gene flow between T. angustula and T. fiebrigi. We characterize 1,003 specimens from southern and southeastern Brazil using mitochondrial DNA and microsatellite analysis and demonstrate that there is ongoing hybridization and introgression between T. angustula and T. fiebrigi and suggest that they may be better regarded as subspecies.

Elaeagnus is a Eurasian tree with 77 species worldwide. In this study, ISSR markers were used to establish the level of genetic relationships and polymorphism across nine genotypes of Elaeagnus angustifolia collected from 9 different regions of West Azarbaijan province. The ISSR analysis with 11 anchored primers also generated 116 scorable loci, of which 92 were polymorphic (79.3%). The estimated Jaccard similarity coefficient ranged from 0.44 to 0.76 for the ISSR markers. Cluster analysis was carried out, based on the Unweighted Pair Group Method with Arithmetic Averages (UPGMA) and the dendrogram drawn with the help of the NTSYSpc 2.02 software. The analysis revealed 5 main clusters for the ISSR data. According to our results, there is a relatively high genetic distance across E. angustifolia genotypes in the West Azarbaijan province of Iran. Furthermore, it could be inferred that ISSR markers are suitable tools for the evaluation of genetic diversity and relationships within the Elaeagnus genus. A Elaeagnus é uma árvore da Eurásia com 77 espécies em todo o mundo. Neste estudo, marcadores ISSR foram usados para estabelecer o nível de relações genéticas e polimorfismo entre nove genótipos de Elaeagnus angustifolia, coletados em 9 diferentes regiões da província do Azerbaijão Ocidental. A análise ISSR, com 11 primers ancorados, também gerou 116 loci contáveis, dos quais 92 polimórficos (79,3%). O coeficiente de similaridade de Jaccard estimado, variou de 0,44 a 0,76 para os marcadores ISSR. A análise de agrupamento foi realizada com base no Método não-ponderado de pares não-agrupados, com médias aritméticas (UPGMA), e a dendrograma elaborada com a ajuda do software NTSYSpc 2.02. A análise revelou cinco grupos principais para os dados ISSR. De acordo com nossos resultados, há uma distância genética relativamente alta entre genótipos de E. angustifolia na província de Azarbaijan Ocidental no Iran. Além disso, pode-se inferir que os marcadores ISSR são ferramentas adequadas para a avaliação da diversidade genética e as relações dentro do gênero Elaeagnus.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:28:45Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:28:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-01 This study describes the comparison of three methods for genotyping of Mycobacterium tuberculosis, namely MIRU-VNTR (mycobacterial interspersed repetitive units-variable number of tandem repeats), spoligotyping and, for the first time, MLST (Multilocus Sequence Typing). In order to evaluate the discriminatory power of these methods, a total of 44 M. tuberculosis isolates obtained from sputum specimens of patients from Brazil were genotyped. Among the three methods, MLST showed the lowest discriminatory power compared to the other two techniques. MIRU-VNTR showed better discriminatory power when compared to spoligotyping, however, the combination of both methods provides the greatest level of discrimination and therefore this combination is the most useful genotyping tool to be applied to M. tuberculosis isolates. © 2013 Elsevier B.V. Departamento de Análises Clínicas, Toxicológicas e Bromatológicas Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista Júlio de Mesquita Filho Department of Zoology University of Oxford, Oxford Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista Júlio de Mesquita Filho

Arachis pintoi and A. repens are legumes with a high forage value that are used to feed ruminants in consortium systems. Not only do they increase the persistence and quality of pastures, they are also used for ornamental and green cover. The objective of this study was to analyze microsatellite markers in order to access the genetic diversity of 65 forage peanut germplasm accessions in the section Caulorrhizae of the genus Arachis in the Jequitinhonha, São Francisco and Paranã River valleys of Brazil. Fifty-seven accessions of A. pintoi and eight of A. repens were analyzed using 17 microsatellites, and the observed heterozygosity (HO), expected heterozygosity (HE), number of alleles per locus, discriminatory power, and polymorphism information content were all estimated. Ten loci (58.8%) were polymorphic, and 125 alleles were found in total. The HE ranged from 0.30 to 0.94, and HO values ranged from 0.03 to 0.88. By using Bayesian analysis, the accessions were genetically differentiated into three gene pools. Neither the unweighted pair group method with arithmetic mean nor a neighbor-joining analysis clustered samples into species, origin, or collection area. These results reveal a very weak genetic structure that does not form defined clusters, and that there is a high degree of similarity between the two species.

Coffee leaf rust is the most limiting disease for coffee cultivation in Brazil. Despite its importance, relatively little is known about the genetic diversity of Hemileia vastatrix, the rust causal agent. In this work, the DNA from 112 monopustule isolates from different geographic locations and coffee genotypes were analysed by amplified fragment length polymorphisms (AFLP). The objectives were to assess the influence of the host and geographic origin on the diversity and population differentiation in H. vastatrix. The fungal population showed a low level of genotypic diversity. Gene diversity (h) was 0·027 and the hypothesis of random mating in the total population was rejected, but evidence for recombination was found for two subpopulations (Sao Paulo and Parana). The analysis of molecular variance revealed that 90% of the genetic distribution of the pathogen occurs among isolates within the subpopulation (states or host of origin). There was no correlation between geographic and genetic distance (r = −0·024, P = 0·74), which together with the high number of migrants and the low degree of differentiation in populations of H. vastatrix, is consistent with the fact that the inoculum is probably easily dispersed by wind over long distances, allowing dispersal of the pathogen among coffee growing areas in Brazil. Therefore, it is difficult to predict the durability of resistant sources to coffee rust. The recommendation for the breeding programmes is thus to incorporate multigenic resistance as a control strategy.

O objetivo deste trabalho foi determinar a variabilidade genética e a expressão de caracteres de interesse forrageiro em espécies de Paspalum. Os experimentos foram conduzidos em diferentes locais e anos de cultivo, em delineamento de blocos ao acaso, com três repetições. Foram avaliados cinco acessos de P. nicorae e dois de P. guenoarum, além da cultivar Pensacola (P. notatum), utilizada como testemunha. Foram quantificados os seguintes caracteres: relação folha/colmo, índice de colheita e massa de matéria seca total, de folhas e de colmo. Tanto os efeitos principais (genótipos, anos e locais de cultivo) quanto a interação entre os fatores tiveram influência significativa sobre os caracteres avaliados. Os acessos avaliados apresentam variabilidade genética em caracteres de interesse forrageiro, bem como desempenho variável de acordo com o local e o ano de cultivo. A produção de matéria seca total e de folhas são os caracteres que mais contribuem para a detecção da variabilidade genética observada, independentemente do ano de avaliação. The objective of this work was to determine the genetic variability and the expression of traits of interest for forage production in species of Paspalum. The experiments were carried out in different locations and crop years in randomized block design with three replicates. Five accessions of P. nicorae and two of P. guenoarum were evaluated, besides the cultivar Pensacola (P. notatum), used as a control. The following traits were determined: leaf/stalk ratio; harvest index; and total, leaf, and stalk dray matter. Both main effects (genotype, years, and locations) and the interactions among factors had significant influence on the evaluated traits. The evaluated accessions showed genetic variability in traits of interest for forage production, and their performance varied according to the location and year of cultivation. Total and leaf dry matter production are the traits that most contribute to the detection of the observed genetic variability, regardless of the year of evaluation.

O objetivo deste trabalho foi avaliar descritores quantitativos e estimar parâmetros genéticos em genótipos de mamoeiro (Carica papaya). Foi instalado um experimento em blocos aumentados, para a avaliação de 27 genótipos, entre cultivares, variedades melhoradas e variedades locais, com o uso de 30 descritores relacionados à planta, folhas, flores, frutos e sementes. Após diversos ciclos de melhoramento, os genótipos ainda mostravam ampla variabilidade quanto aos descritores avaliados. A maior parte da variação fenotípica ocorreu em razão da variância genotípica. A herdabilidade variou de 60,48 a 99,05% e, em 80% dos casos, foi superior a 80,46%. A razão entre o coeficiente de variação genético e o ambiental foi maior do que a unidade para 63% das características. Há diferenças agronômicas suficientes para uso dos genótipos "per se" ou como parentais em programas de melhoramento, em razão de agregarem variação genética, qualidade de frutos e tipo agronômico. The objective of this work was to evaluate quantitative descriptors and to estimate genetic parameters in genotypes of papaya (Carica papaya). An experiment was settled using augmented blocks, for the evaluation of 27 genotypes, among cultivars, improved lines and local varieties with 30 descriptors related to the plant, leaves, flowers, fruit and seeds. After several cycles of breeding, the genotypes still showed broad variability for the evaluated descriptors. Most of the phenotypic variation occurred due to genetic variance. The heritability ranged from 60.48 to 99.05%, and in 80% cases it was higher than 80.46%. The ratio between genetic and environmental coefficients of variation, was greater than the unity for 63% traits. There are enough agronomic differences which allow for the use of the genotypes "per se" or as parents in breeding programs because they aggregate genetic variation, fruit quality and agronomic type.

This study constitutes a first attempt to describe the genetic population structure of Mycobacterium tuberculosis circulating in Salvador, Bahia State, Brazil. A total of 56 confirmed cases of pulmonary tuberculosis, identified between March and June 2008, were analyzed using restriction fragment length polymorphism (IS6110-RFLP). The study population was characterized by a predominance of males (71.43%) over 30 years of age (68.75%). Forty-one isolates were found to belong to a single pattern (73.2%), while 15 (26.7%) were found in group patterns, forming six clusters. The higher level of diversity observed is much more suggestive of endogenous reactivation than recent transmission. Este é o primeiro estudo realizado na Bahia, Brasil, visando à descrição da estrutura da população genética circulante do Mycobacterium tuberculosis na cidade de Salvador. Um total de 56 casos confirmados de tuberculose pulmonar, identificados entre março e junho de 2008, foi analisado pelo método Restriction Fragment Lenght Polymorphism (IS6110-RFLP). A população de estudo foi caracterizada como a maioria do sexo masculino (71,43 %), idade acima de 30 anos (68,75%). Quarenta e um isolados (73,21%) com padrão único, enquanto 15 (26,75%) apresentaram padrões agrupáveis, formando seis clusters. A alta taxa de diversidade das cepas de M. tuberculosis observada é mais sugestiva de reativação endógena do que transmissão recente.

O objetivo neste trabalho foi analisar a diversidade genética de 14 materiais de Lotus corniculatus L. por meio de marcadores microssatélites. Foram analisados quatro cultivares e uma população de L. corniculatus e seus respectivos genótipos selecionados visando tolerância e sensibilidade ao alumínio. Foram utilizados 17 pares de primers que detectaram 36 alelos nos 17 locos microssatélites, com média de 2,25 alelos por loco. O resultado da análise de agrupamento com base nos índices de similaridade mostrou a formação de três grupos: um englobando germoplasmas e genótipos selecionados para sensibilidade ao alumínio e outros dois formados por genótipos selecionados visando tolerância ao alumínio tóxico. A análise molecular foi eficiente para detectar e quantificar a variabilidade entre os genótipos, acrescentando informações úteis ao programa de melhoramento. O uso de marcadores microssatélites permite a distinção de genótipos oriundos de um programa de seleção visando tolerância à toxidez por alumínio. As seleções realizadas originam genótipos polimórficos em relação às populações originais. The aim of this work was to analyze the genetic diversity of 14 Lotus corniculatus L. materials through microsatellite markers. Four cultivars and one population of L. corniculatus and their respective genotypes selected were analyzed aiming aluminium tolerance and sensibility. The 17 markers used detected a total of 36 alleles, with an average of 2.25 alleles per locus. The result of the similarity analyses showed the formation of three groups: one enclosing germplasm and selected genotypes for aluminium sensibility, while the other two groups were formed by selected genotypes for aluminium tolerance. The molecular analysis was efficient in detecting and quantifying the variability among the genotypes, adding useful information to the breeding program. The utilization of microsatellite markers permitted the distinction of genotypes originated from a selection program aiming aluminium tolerance. The performed selections originate polymorphic genotypes in relation to the original populations.

Because of the increasing demand of the industry for the production of essential oils, studies highlight the genetic variability of Piper hispidinervum and P. aduncum species according to their patterns of spatial distribution, showing the Amazon region as the source of superior genetic material in the production of safrole and dillapiole. Thus, the objective this study was to characterize the morphology and the phytochemistry of Piper hispidinervum and P. aduncum populations in the Active Germplasm Bank of Embrapa Acre to generate subsidies for the genetic improvement of these species. The results showed that the average values for leaf width and length were 141.67 and 48.04 mm, and petioles length and diameter measurements were 2.83 and 1.78 mm for P. hispidinervum and 189.22; 67.74; 6.03 and 2.22 mm for P. aduncum respectively. The average height and canopy volume measurements were 2.39 m and 6.30 m3 and 2.70 m and 7.78 m3 respectively for each species. For P. hispidinervum, the population with higher performance indried yield and content of safrole was population 02, with 3.9%, and the population 04 showed 94.3% safrole content, both with genetic material from the region of Acrelândia and Plácido de Castro. To P. aduncum, the populations with better performance were 207, 208 and 209, forming a homogeneous group with dried yield average of 3.8% and dillapiol content of 84-85%. Such populations are indicated for selection in breeding program of these species due to better performance. Estimulados pela crescente demanda da indústria pela produção de óleos essenciais, estudos ressaltam a variabilidade genética das espécies de Piper hispidinervum e P. aduncum, de acordo com seus padrões espaciais de distribuição, mostrando-se a região Amazônica como origem de materiais genéticos superiores para a produção de safrol e dilapiol. Objetivou-se, com este trabalho, caracterizar morfológica e fitoquimicamente populações de Piper hispidinervum e de P. aduncum, do Banco Ativo de Germoplasma da Embrapa Acre, de forma a gerar subsídios para o melhoramento genético das espécies. Os resultados mostraram que os valores médios para largura e comprimento de folha e comprimento e diâmetro de pecíolo foram: 141,67; 48,04; 2,83 e 1,78 mm, respectivamente, para P. hispidinervum, e 189,22; 67,74; 6,03 e 2,22 mm, para P. aduncum. Os valores médios de altura e volume de copa foram 2,39 m e 6,30 m3 e 2,70 m e 7,78 m3, respectivamente, para cada espécie. Para P. hispidinervum, as populações com maior desempenho no rendimento em base livre de umidade (BLU) e teor de safrol foram 02, com 3,9% de rendimento e 04 com 94,3% de safrol, ambas com material genético originário dasregiões de Acrelândia e Plácido de Castro. Para P. aduncum, as populações com melhor desempenho foram 207, 208 e 209, originárias da Microrregião de Cruzeiro do Sul, formando um grupo homogêneo, com rendimentos em BLU médios de 3,8% e teor de dilapiol de 84 a 85%. Essas populações de melhor desempenho são indicadas para seleção, no programa de melhoramento genético das espécies.

The purpose of this study was to characterize culturally, enzymatically and pathogenically Alternaria alternata isolates obtained of tangerine/tangor (TP) and rough lemon (RLP). Significant differences were observed regarding mycelial growth speed and sporulation of isolates when cultivated in starch-agar (SA), potato-dextrose-agar (PDA) and tomato juice agar (V8) media. SA and PDA media promoted better mycelial growth and sporulation, respectively. Eight genetic similarity groups were defined through isoenzymatic characterization but without correlation between isolates and host or site of origin. All isolates produced amylase, cellulase, polygalacturonase and pectynase; however, no lipolytic or proteolytic activity was observed. Disease incubation period varied between 24 to 48 h for all isolates in all phenological stages of the inoculated fruit. Symptomatic fruit incidence in most tangerine and tangor isolates was higher in stage F3 compared to stages F4 and F5. Alternaria alternata have the ability to perform hyphal anastomosis indicating that this can be a mechanism used by the fungus to increase genetic variability.

O objetivo deste trabalho foi caracterizar a diversidade genética dentro e entre cultivares locais e comerciais de feijão, por meio de marcadores RAPD, e avaliar a capacidade destes em agrupar genótipos de feijão de acordo com o centro de domesticação e coloração de semente. Foram avaliadas 35 cultivares, 13 comerciais e 22 locais, de diversas regiões do Rio Grande do Sul. As distâncias genéticas foram obtidas pelo complemento do coeficiente de similaridade de Sorensen-Dice e a representação simplificada destas distâncias realizada mediante um dendrograma. Marcadores RAPD foram eficientes ao agrupar cultivares de acordo com o centro de domesticação, mas não foram capazes de separar as cultivares de acordo com a coloração da semente. Cultivares locais e comerciais, mesoamericanas, foram agrupadas separadamente. Cultivares comerciais, em cultivo no Rio Grande do Sul apresentam alto grau de similaridade. The objective of this work was to characterize the genetic diversity within and among cultivars and landraces of common bean from RAPD markers analysis, and to evaluate the capacity of this markers in clustering common bean genotypes according to domestication centers and seed color. Thirty five common bean genotypes including 13 commercial cultivars and 22 landraces, from State of Rio Grande do Sul, Brazil, were evaluated. Genetic distances were calculated using Sorensen-Dice's similarity coefficient, displayed in a dendrogram. RAPD markers were efficient in separating cultivars and landraces according to domestication centers, but not according to seed color. Mesoamerican commercial cultivars and landraces have been clustered in different groups. A high degree of similarity was observed among cultivars in use in Rio Grande do Sul.

Este trabalho teve como objetivo caracterizar frutos de genótipos de cajazeira (Spondias mombin L.) visando identificar materiais de interesse industrial e para trabalhos de melhoramento. Frutos de 30 genótipos foram caracterizados avaliando-se: pH, sólidos solúveis totais (SST), acidez total titulável (ATT), vitamina C, relação sólidos solúveis total/acidez total titulável, açúcares totais, rendimento industrial, massa total do fruto, massa da semente, massa da casca, massa da polpa e porcentual de rendimento de polpa. Os resultados (médias de três amostras) foram avaliados por estatística descritiva utilizando-se medida de tendência central (média) e de variabilidade de dados (desvio-padrão e coeficiente de variação). Foram realizadas análises estatísticas multivariadas, utilizando-se as técnicas de análise de agrupamento e análise de componentes principais. Os frutos que apresentaram melhores características para o processamento foram os provenientes dos genótipos AJ04UB, VS07UB, TF25TN, TF26TN, TF29TN, TF30TN e TF31TN. A análise de agrupamento mostrou a formação de quatro grupos de genótipos, o que demonstra a variabilidade genética existente na espécie. The objective of this work was to characterize fruits of true yellow mombin (Spondias mombin L.) genotypes to identify materials of industrial interest and for breeding works. Fruits of 30 genotypes were characterized by evaluation of pH, total soluble solid (TSS), titratable total acidity (TTA), vitamin C, TSS/TTA rate, total sugars, industrial income, total fruit mass, seed mass, rind mass, pulp mass, and percentage of pulp income. The results (average of three samples) were evaluated by descriptive statistics using central trend (average) and variability of data (standard error and coefficient of variation). Multivaried statistical analyses were carried out, by means of grouping and main components techniques. Fruits from the genotypes AJ04UB, VS07UB, TF25TN, TF26TN, TF29TN, TF30TN and TF31TN presented the best features for processing. Grouping analysis showed formation of four genotypes groups showing the existence of genetic variability in the species.

Objetivou-se avaliar a reação de 58 cultivares de cevada a Drechslera teres, agente causal da mancha-em-rede, bem como a variabilidade patogênica e freqüência de sintomas do patógeno. A reação das cultivares foi estimada com auxílio de uma escala de notas de 0 a 4, em que zero (0) representa a ausência de sintomas, e 4 representa os sintomas típicos da mancha-em-rede. O mesmo método foi utilizado para avaliar a variabilidade patogênica de 25 isolados oriundos do Sul do Brasil. Seis isolados de boa capacidade de esporulação foram utilizados para comparar o número de lesões e a severidade da doença. As cultivares diferiram quanto à reação a D. teres, e identificaram-se as três cultivares, BR 2, EMBRAPA 43 e PFC 8590, como fontes de resistência moderada à doença. Em testes de 25 isolados de D. teres, inoculados na concentração de 1,7x10(4) conídios/mL, detectaram-se diferenças significativas entre os isolados, evidenciando diferenças na sua virulência. Pelo sistema de nomenclatura de Limpert & Müller, foi possível diferenciar padrões de virulência de isolados oriundos de diferentes regiões do Sul do Brasil. O número de lesões e a severidade foram intimamente relacionadas com o local de origem do isolado.

Eucalyptus rust caused by Puccinia psidii is responsible for losses of approximately 20% of young Eucalyptus plants, depending on the environmental conditions and the geographic location. Despite its economic importance, there are few studies describing the genetic variability in P. psidii populations that infect different host plants. In the present study, we evaluated the ribosomal DNA internal transcribed spacer region (rDNA-ITS) using polymerase chain reaction denaturing gradient gel electrophoresis and terminal restriction fragment length polymorphism to assess the genetic variability in P. psidii populations infecting different Eucalyptus spp. and hybrids, as well as guava, jabuticaba, and syzygium. These culture-independent methods were efficient in differentiating populations based on the host species from which they were collected. In general, the results from both techniques showed that the populations collected from guava, jabuticaba, and syzygium were different from and had a greater level of diversity than the Eucalyptus rust populations. The sequencing of cloned rDNA-ITS fragments confirmed that the vast majority of the profiles generated were from P. psidii. This analysis also revealed interesting single-nucleotide polymorphisms. Therefore, these culture-independent methods are suitable for the rapid assessment of genetic variability within and between populations of this biotrophic fungus on a variety of host species and could be a tool to study the evolution of this pathogen and its interactions with host plants.

The aim of these studies was to investigate whether residual toxic effects of exposing soybean root nodule bacteria to Al in a solid defined media (SDM) alter tolerance to Al, survival, sensitivity to antibiotics, N2 fixation effectiveness and genetic diversity of Bradyrhizobium strains. After being exposed four times to Al, strains showed variation in Al tolerance but there was no evidence of change in their original Al tolerance, sensitivity to the antibiotics or genetic diversity. Exposure of Bradyrhizobium strains to SDM plus Al did not alter biological N2 fixation effectiveness of five strains. Strain SEMIA 587 showed a reduction in its N2 fixation effectiveness but it seems that it was just a superficial toxic effect because one single passage through the plant eliminated this effect. Residual Al did not cause increases in Al tolerance and reductions in the survival and N2 fixation effectiveness of Bradyrhizobium strains USDA 143, SEMIA 586, SEMIA 5019, SEMIA 5039 and SEMIA 5073. It also did not alter the resistance to antibiotics of strains USDA 143, SEMIA 5039 and SEMIA 5073, and the genetic diversity of the strains SEMIA 587 and SEMIA 5019. O objetivo deste trabalho foi investigar se os efeitos tóxicos residuais do Al afetam a tolerância Al, sobrevivência, sensibilidade a antibióticos, eficiência de fixação de nitrogênio e diversidade genética de estirpes de Bradyrhizobium. Quando os nódulos de bactérias da raiz de soja foram expostos ao Al, em meio sólido por quatro vezes consecutivas, as estirpes de Bradyrhizobium mostraram variações na tolerância ao Al. Não houve alterações nos níveis originais de tolerância ao Al, sobrevivência, sensibilidade aos antibióticos testados e diversidade genética. Cinco das estirpes expostas ao Al não alteraram a eficiência de fixação de nitrogênio. A estirpe SEMIA 587, por sua vez, mostrou uma redução da sua eficiência de fixação de N2, mas apenas superficial, porque uma simples passagem através da planta eliminou esse efeito tóxico. Sucessivas exposições de estirpes de Bradyrhizobium ao Al não aumentam a tolerância ao Al, não reduzem a sobrevivência e a eficiência de fixação simbiótica do N2 das estirpes USDA 143, SEMIA 586, SEMIA 5019, SEMIA 5039 e SEMIA 5073, não alteram a tolerância a antibióticos das estirpes USDA 143, SEMIA 5039 e SEMIA 5073 e não alteram a diversidade genética das estirpes SEMIA 587 e SEMIA 5019.

Objetivou-se, neste trabalho, caracterizar isoenzimaticamente genótipos de arroz (Oryza sativa L.). A produtividade do arroz irrigado no Rio Grande do Sul é elevada, em virtude da alta tecnologia e sistema de irrigação usados, associados ao potencial alcançado pelas cultivares desenvolvidas através de melhoramento genético. Apenas seis ancestrais contribuem com 86% dos genes das cultivares mais plantadas. Como conseqüência desta estreita base genética, as cultivares apresentam um alto grau de parentesco e de similaridade de suas características morfológicas e agronômicas, o que dificulta a identificação varietal. A concorrência com genótipos, como arroz-vermelho e arroz-preto, de difícil controle por serem da mesma espécie que os cultivados, é considerada como um dos maiores problemas da cultura. Análises de isoenzimas podem ser usadas para o estudo da variabilidade e para estimar as relações genéticas existentes entre estes genótipos. Eletroforese em gel de poliacrilamida foi empregada, portanto, para caracterizar, através de isoenzimas de esterase, 6fosfogluconato desidrogenase, fosfoglucoisomerase e isocitrato desidrogenase em sementes e folhas de plântulas, e de fosfatase ácida e aspartato transaminase em folhas de plântulas, as cultivares BR-IRGA 409, BR-IRGA 410, BRS 6 ('Chuí'), BRS 7 ('Taim'), BRS Agrisul, INIA Taquari, El Paso L 144 e IRGA 417, e ecótipos de arroz-vermelho e arroz-preto. A análise de agrupamento, efetuada por meio do coeficiente de Jaccard e pelo método da média aritmética não ponderada (UPGMA), possibilitou a diferenciação de todos os genótipos, à exceção de BRS 6 ('Chuí') e BRS 7 ('Taim'). Três grupos foram identificados, incluindo-se, em um deles, os ecótipos de arroz-vermelho e arroz-preto, que apresentaram 95% de similaridade. The objective of this work was to characterize isoenzymaticly rice (Oryza sativa L.) genotypes. Rice yields obtained in Rio Grande do Sul, Brazil, are high, due to the high technology and the irrigation system used, associated to the genetic potential of the bred cultivars. Six ancestors contribute with 86% of the genetic make up of used cultivars. As a consequence of this narrow genetic basis, they are closely related and show very similar morphological and agronomical characteristics, which turns the varietal identification difficult. The competition with wild genotypes (red and black hulled rice) is considered to be the greatest problem, because they belong to the same species as cultivated rice. Isoenzymes analysis can be used to study variability and to estimate genetic relations among genotypes. Therefore, polyacrylamide gel electrophoresis was used to characterize, through seeds and seedling leaf tissue, esterase, 6-phosphogluconate dehydrogenase, phosphoglucoisomerase and isocitrate dehydrogenase, and seedling leaf tissue acid phosphatase and aspartate transaminase isoenzymes of cultivars BR-IRGA 409, BR-IRGA 410, BRS 6 ('Chuí'), BRS Taim 7 ('Taim'), BRS Agrisul, INIA Taquari, El Paso L 144 e IRGA 417, and ecotypes of red and of black hulled rice. Cluster analysis, using Jaccard coefficient and unweighted pair-group method arithmetic average (UPGM), allowed to differentiate all genotypes, excluding BRS 6 ('Chuí') and BRS 7 ('Taim'). Three groups were identified, including, in one of them, red and black hulled rice ecotypes, with 95% degree similarity.

O objetivo deste trabalho foi estimar a variabilidade de algumas características morfológicas em híbridos de Leucaena leucocephala e L. diversifolia (Leguminosae). Foram estabelecidos 20 genótipos, com 30 indivíduos cada, dispostos em seis blocos casualizados. As características morfológicas analisadas foram: comprimento de folha, número de pares de folíolos e foliólulos, número de nectários extraflorais; comprimento e largura de legumes e número de sementes por legume. O menor e o maior comprimento médio de folha foram, respectivamente, 8,6 cm e 30,6 cm. A população apresentou variação de 10,7 a 53,4 pares de foliólulos por folíolo. Em número de pares de folíolos por folha o menor valor médio foi 5,6 e o maior foi 20,3. A média de um nectário extrafloral por folha foi identificada na maioria dos indivíduos. O maior valor médio de número de sementes por legume foi 24,1 e o menor 5,0. Cinco genótipos se destacaram por sua uniformidade em relação às características analisadas. This work aimed to estimate the variability of some morphological characteristics in hybrids of Leucaena. Twenty genotypes, with 30 individuals each, of hybrids between L. leucocephala and L. diversifolia were established in a randomized blocks design with six repetitions. Leaf length, number of pinnae and leaflet pairs, number of extrafloral nectaries, legume length and width and number of seeds per legume were analyzed. Leaf length average values ranged from 8.6 cm to 30.6 cm. Number of leaflets per pinna ranged from 10.7 to 53.4 and the number of pinnae per leaf ranged from 5.6 to 20.3. Most of the individuals presented an average of 1.0 extrafloral nectary per leaf. The highest average value of number of seeds per legume was 24.1 and the lowest 5.0. Five genotypes were the most uniform considering the characteristics analyzed.

The objective of this study was to characterize 17 accessions of Sesbania, representing S. exasperata, S. grandiflora, S. sesban, S. tetraptera and S. virgata at the seedling stage, and to evaluate the initial development during the first two months after planting. The trial was conducted in a greenhouse in a randomized block design, with 4 replications and 5 plants per plot. The traits recorded were: plant height (PH), from four observations at 15-day intervals, at 17, 32, 47 and 62 days after planting; length of hypocotyl (LH) and epicotyl (LEP); length (LE1) and width (WE1) of the first eophyll; and number of leaflet pairs of the second metaphyll (NLP), evaluated 17 days after planting. Univariate analyses of variance were performed, estimating the genetic parameters: coefficient of genotypic determination (b) and of genetic variation (CVg). Cluster analysis was also obtained, using the average Euclidean distance and Unweighted pair group method of arithmetic average (UPGMA) method. At 17 days after planting, S. exasperata presented the highest PH, followed by S. virgata. At 62 days after planting, S. sesban registered the highest PH. Length of hypocotyl displayed inter but not intraspecific variation. The characters LEP, LE1, WE1 and NLP showed both inter and intraspecific variation. Cluster analysis indicated the existence of 7 groups, separating the species and revealing intraspecific variation as well. The occurrence in low frequencies of two unifoliolate opposite eophylls for some species was observed, as well as bi- or trifoliolate first eophylls for one of the S. sesban accessions. These informations are basic for the selection of traits to be utilized for characterization and differentiation of Sesbania germplasm at the juvenile phase. Este estudo teve como objetivo caracterizar 17 acessos de Sesbania, representando as espécies S. exasperata, S. grandiflora, S. sesban, S. tetraptera e S. virgata no estágio de plântula, avaliando também o desenvolvimento inicial nos primeiros dois meses após o plantio. O ensaio foi instalado em casa-de-vegetação, em blocos casualizados com 4 repetições e 5 plantas por parcela. Avaliaram-se os seguintes caracteres: altura da planta (AP) em 4 avaliações, espaçadas de 15 dias, aos 17, 32, 47 e 62 dias após o plantio; comprimento do hipocótilo (CH) e do epicótilo (CEP); comprimento (CE1) e largura (LE1) do eófilo 1; e número de pares de folíolos do metáfilo 2 (NPF). A primeira AP e os demais caracteres foram avaliados aos 17 dias do plantio. Foram realizadas análises de variância univariada, estimando-se os parâmetros genéticos: coeficiente de determinação genotípica (b) e de variação genética (CVg), e uma análise de agrupamento, usando distância Euclideana média e método UPGMA (Unweighted pair group method of arithmetic average). Aos 17 dias do plantio, S. exasperata apresentou maior AP, seguida de S. virgata. Aos 62 dias do plantio, S. sesban apresentou a maior AP. O caráter CH apresentou variação inter mas não intraespecífica. Já os caracteres CEP, CE1, LE1 e NPF mostraram variação tanto inter como intraespecífica. A análise de agrupamento indicou a existência de 7 grupos, separando as espécies e mostrando variação intraespecífica. Foi também observada a ocorrência, em baixas freqüências, de dois eófilos unifoliolados e opostos para algumas espécies, bem como a ocorrência de eófilos nº 1 bi- ou trifoliolados para um dos acessos de S. sesban. Estas informações são básicas para a escolha de caracteres a serem utilizados na fase juvenil para a diferenciação e caracterização de germoplasma de Sesbania.

O objetivo do presente estudo foi avaliar a diversidade genética de Salminus brasiliensis coletados em três períodos diferentes na escada de transposição da hidrelétrica de Canoas I no rio Paranapanema (Brasil). Os peixes foram coletados no dia 14 (CI14), 18 (CI18) e 25 (CI25) do mês de fevereiro de 2008. Foram avaliados oito iniciadores com a técnica de RAPD. Dos 105 fragmentos amplificados pelos iniciadores, 79 foram polimórficos (75,2%), 32 tiveram diferenças significativas (p

O objetivo deste trabalho foi estimar a divergência genética de progênies de pupunheira, com base em variáveis agronômicas do palmito. O delineamento experimental em blocos ao acaso foi utilizado em látice triplo 10x10, com 100 tratamentos (progênies) e três repetições. Foram feitas as seguintes avaliações: massa da base do palmito, produtividade do palmito de primeira e de segunda qualidade, número de plantas por parcela e diâmetro do palmito. A divergência genética foi estimada pela distância generalizada de Mahalanobis, como medida de dissimilaridade, e pelo método de otimização de Tocher e variáveis canônicas, na formação de grupos. As progênies formaram 26 grupos distintos. A variância acumulada pelas três primeiras variáveis canônicas foi de 75,12%. Planta por parcela e massa do palmito de segunda, indiretamente relacionada à massa do palmito de primeira, foram os caracteres mais importantes na discriminação das progênies, na primeira variável canônica (35,77%). A massa da base do palmito apresentou relação indireta com a produtividade do palmito de segunda e plantas por parcela, na segunda variável canônica (22.93%), e com a massa do palmito de primeira na terceira variável canônica (16,42%). Dezessete progênies de quatro grupos divergentes (G3, G5, G11 e G12) têm potencial para seleção quanto à produtividade de palmito no programa de melhoramento da pupunheira.

Microsatellite markers were developed for population genetic analyses of the Neotropical tree Eugenia dysenterica DC (Myrtaceae), after construction of a shotgun genomic library for microsatellite discovery. Nine primers were designed, of which 5 yielded amplified product. These primers were polymorphic for 97 individuals collected in 3 distinct localities. The number of alleles per locus (primer) ranged from 3 to 11 and expected heterozygosities varied from 0.309 to 0.884. The probability of locus identity was ~1.88 x 10(-4) and the probability of paternity exclusion was ~0.9367. The 5 microsatellite primer pairs may be suitable for population genetic studies such as parentage and fine-scale genetic analyses of this species.

INTRODUCTION: The precise identification of the genetic variants of the dengue virus is important to understand its dispersion and virulence patterns and to identify the strains responsible for epidemic outbreaks. This study investigated the genetic variants of the capsid-premembrane junction region fragment in the dengue virus serotypes 1 and 2 (DENV1-2). METHODS: Samples from 11 municipalities in the State of Paraná, Brazil, were provided by the Central Laboratory of Paraná. They were isolated from the cell culture line C6/36 (Aedes albopictus) and were positive for indirect immunofluorescence. Ribonucleic acid (RNA) extracted from these samples was submitted to the reverse transcription polymerase chain reaction (RT-PCR) and nested PCR. RESULTS: RT-PCR revealed that 4 of the samples were co-infected with both serotypes. The isolated DENV-1 sequences were 95-100% similar to the sequences of other serotype 1 strains deposited in GenBank. Similarly, the isolated DENV-2 sequences were 98-100% similar to other serotype 2 sequences in GenBank. According to our neighbor-joining tree, all strains obtained in this study belonged to genotype V of DENV-1. The DENV-2 strains, by contrast, belonged to the American/Asian genotypes. CONCLUSIONS: The monitoring of circulating strains is an important tool to detect the migration of virus subtypes involved in dengue epidemics.