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Rendón-Anaya, Martha et. al., [Background] Modern civilization depends on only a few plant species for its nourishment. These crops were derived via several thousands of years of human selection that transformed wild ancestors into high-yielding domesticated descendants. Among cultivated plants, common bean (Phaseolus vulgaris L.) is the most important grain legume. Yet, our understanding of the origins and concurrent shaping of the genome of this crop plant is limited., [Results] We sequenced the genomes of 29 accessions representing 12 Phaseolus species. Single nucleotide polymorphism-based phylogenomic analyses, using both the nuclear and chloroplast genomes, allowed us to detect a speciation event, a finding further supported by metabolite profiling. In addition, we identified ~1200 protein coding genes (PCGs) and ~100 long non-coding RNAs with domestication-associated haplotypes. Finally, we describe asymmetric introgression events occurring among common bean subpopulations in Mesoamerica and across hemispheres., [Conclusions] We uncover an unpredicted speciation event in the tropical Andes that gave rise to a sibling species, formerly considered the “wild ancestor” of P. vulgaris, which diverged before the split of the Mesoamerican and Andean P. vulgaris gene pools. Further, we identify haplotypes strongly associated with genes underlying the emergence of domestication traits. Our findings also reveal the capacity of a predominantly autogamous plant to outcross and fix loci from different populations, even from distant species, which led to the acquisition by domesticated beans of adaptive traits from wild relatives. The occurrence of such adaptive introgressions should be exploited to accelerate breeding programs in the near future., This work was supported by the Ibero-American Programme for Science, Technology and Development - CYTED (PhasIbeAm project); Spanish Government - Ministry of Economy and Competitiveness (EUI2009-04052, BIO2011-26205), “Centro de Excelencia Severo Ochoa 2013-2017,” SEV-2012-0208 and Project PT13/0001/0021 (ISCIII - Subdirección General de Evaluación y Fomento de la Investigación/FEDER “Una Manera de hacer Europa”); Brazilian Government—National Council for Scientific and Technological Development - CNPq/Prosul (490725/2010-4); Ministerio de Ciencia, Tecnología e Innovación Productiva de la República Argentina; Consejo Nacional de Ciencia y Tecnología - Conacyt, Mexico (J010-214-2009, Fronteras 2015-2/814); and U.S. government: USDA National Institute of Food and Agriculture (2013-67013-21224. M. R-A. and J.M.M.-V. are indebted to Conacyt for a doctoral fellowship.

Drought stress, particularly during the flowering and grain-filling stages of growth, contributes to serious yield loss in common bean (Phaseolus vulgaris L.). The aim of this study was to identify genes induced in response to drought stress using transcriptome analysis of contrasting genotypes. Using leaf tissues of tolerant (BAT 477) and susceptible common bean genotypes (Perola), collected at the flowering and grain-filling stages, four complementary deoxyribonucleic acid representational difference analysis subtractive libraries were constructed and then sequenced. A total of 7,203 (77.6 %) sequences with an average sequence size of 570 bp were considered valid, for a combined 4 Mbp sequence. According to a differential display analysis, 802 expressed sequence tags, distributed across 67 contigs, were differentially expressed by the tolerant (37 contigs) and susceptible genotypes (30 contigs) after identification under drought conditions during the two investigated plant developmental stages. Of these differential contigs, the 13 most frequent genes were exclusive to the tolerant genotype. Based on BLAST2GO, 73 % of the gene sequences were annotated and 12 % showed mapping results, with the highest similarity rate corresponding to Glycine max (41 %). According to gene ontology functional analysis, 48 % of the sequences were attributed to cell metabolic processes. Overall, 8.3 % of the transcribed sequences exhibited similarity to transcription factors, predominantly those of the AP2-EREBP family (97.8 %). Of the target sequences validated by quantitative real-time polymerase chain reaction, most genes showed an expression level that agreed with that predicted by in silico analysis. Thus, the drought transcriptome dataset is a valuable resource on the variation in these gene sequences, offering the opportunity to identify robust molecular markers tightly linked to trait-controlling loci for use in marker-assisted breeding.

Background: Legumes are the third largest family of angiosperms and the second most important crop class. Legume genomes have been shaped by extensive large-scale gene duplications, including an approximately 58 million year old whole genome duplication shared by most crop legumes. Results: We report the genome and the transcription atlas of coding and non-coding genes of a Mesoamerican genotype of common bean (Phaseolus vulgaris L., BAT93). Using a comprehensive phylogenomics analysis, we assessed the past and recent evolution of common bean, and traced the diversification of patterns of gene expression following duplication. We find that successive rounds of gene duplications in legumes have shaped tissue and developmental expression, leading to increased levels of specialization in larger gene families. We also find that many long non-coding RNAs are preferentially expressed in germ-line-related tissues (pods and seeds), suggesting that they play a significant role in fruit development. Our results also suggest that most bean-specific gene family expansions, including resistance gene clusters, predate the split of the Mesoamerican and Andean gene pools. Conclusions: The genome and transcriptome data herein generated for a Mesoamerican genotype represent a counterpart to the genomic resources already available for the Andean gene pool. Altogether, this information will allow the genetic dissection of the characters involved in the domestication and adaptation of the crop, and their further implementation in breeding strategies for this important crop., La lista completa de autores que integran el documento puede consultarse en el archivo., Facultad de Ciencias Exactas, Instituto de Biotecnologia y Biologia Molecular

The decrease in the per capita consumption of beans has been partially attributed to their lengthy cooking time and the aggregated capital costs of their preparation. The aim of this study was to map microsatellite (SSR) markers linked to quantitative trait loci (QTLs) that govern the cooking time of common beans. An F2 generation consisting of 140 families was generated from a cross between lines CNFM7875 and Laranja. The cooking time of the F2:4 and F2:5 generations was then evaluated, and the latter generation was tested in two environments. The analysis of variance found a significant effect for the interactions between the families (P < 0.01) in both the F2:4 and F2:5 generations, as well as for the group analyses performed in the two environments. The experimental coefficient of variation varied from 9.42 to 17.94%. The Pearson’s correlation test indicated no significant association between water absorption and cooking time. The heritability coefficients had values of 0.532 and 0.739 for the F2:5 families evaluated at the two different locations, and the group analysis of the F2:5 generation indicated that there was a significant genotype × environment interaction. Of the 105 polymorphic SSRs evaluated, 91 mapped to 12 linkage groups with an estimated map size of 1,303.7 cM. Six significant QTLs were detected in both environments, and the percentage of the phenotypic variation that was explained by these loci ranged from 11.54 to 21.63%. As the genetic control was oligogenic, the identification of QTLs should serve as an optimal starting point for the implementation of a selection program.

We identified 14 microsatellite loci for the wolf fish, Hoplias malabaricus (Erythrinidae), from a genomic shotgun library. Twenty-five primers were designed, and 48 individuals of H. malabaricus from four localities of northwest Goias, in central Brazil, were genotyped to characterize the polymorphism at each locus. Fourteen primers amplified clearly interpretable products using a single PCR protocol; six loci were polymorphic, but with a low number of alleles per locus (2 or 3). Expected heterozygosities for polymorphic loci ranged from 0.136 to 0.505. Combined paternity exclusion probability (0.638) was low and combined genetic identity (0.056) was high in studies of parentage. The low polymorphism may be due to the small microsatellite size and the large size of the motifs.

Knowledge of natural diversity and population structures of wild species, which might be related to cultivated species, is fundamental for conservation and breeding purposes. In this study, a genetic characterization of a large population of Oryza glumaepatula, occurring in a 10 km2 area located at Tamengo Basin (Paraguay River, Brazil), was performed using SSR markers. This population is annually dragged from the river to permit navigation; one goal of this study was to examine the impact of this removal on genetic variability. From 18 polymorphic SSR markers, a total of 190 alleles were detected in a sample of 126 individuals, with an average of 10.3 alleles/locus, and a H e of 0.67. The five QTL-related markers showed an average H e value of 0.56, while the remaining 13 markers detected an average estimate of 0.70. An apparent outcrossing rate of 30%, a high proportion of alleles at low frequencies (56%), and the presence of exclusive alleles (9.5%) were found, with strong evidence of the establishment of individuals from different populations upstream in the Paraguay River. For conservation purposes, the river drag has no effect on the population. However, periodical seed collection from the Corumba population can preserve part of the genetic variability present in upstream populations reducing the need for upriver collecting expeditions.

The reduced genetic variability of modern rice varieties (Oryza sativa) is of concern because it reduces the possibilities of genetic gain in breeding programs. Introgression lines (ILs) containing genomic fragments from wild rice can be used to obtain new improved cultivars. The objective of the present study was to perform the agronomic and molecular characterizations of 35 BC2F8 ILs from the cross O. glumaepatula x O. sativa, aiming to select high-yielding ILs to be used in rice-breeding programs. All 35 ILs were field evaluated in the season 2002/2003 in three locations and the 15 best performing ones were evaluated in the season 2003/2004 in five locations. In 2003/2004, six ILs (CNAi 9934, CNAi 9931, CNAi 9930, CNAi 9935, CNAi 9936, and CNAi 9937) showed the highest yield means and were statistically superior to the controls Metica 1 and IRGA 417. Molecular characterization of the 35 ILs was performed with 92 microsatellite markers distributed on the 12 rice chromosomes and a simple regression quantitative trait locus analysis was performed using the phenotypic data from 2002/2003. The six high-yielding ILs showed a low proportion of wild fragment introgressions. A total of 14 molecular markers were associated with quantitative trait loci in the three locations. The six high-yielding ILs were incorporated in the Embrapa breeding program, and the line CNAi 9930 is recommended for cultivation due to additional advantages of good grain cooking and milling qualities and high yield stability. The O. glumaepatula-derived ILs proved to be a source of new alleles for the development of high-yielding rice cultivars. Made available in DSpace on 2022-04-28T18:23:56Z (GMT). No. of bitstreams: 1 gmr.pdf: 976098 bytes, checksum: 711688009f9607024bdc10d13a2af4b6 (MD5) Previous issue date: 2008

The study aimed to evaluate the capacity of SSR markers to detect the gene flow between the red rice (RR) and the cultivated rice (CR). SSR is currently used in plant genomic analysis due to the high information content, to be co-dominant, and based on the PCR reaction. The field experiment was organized in ten concentric circles, 5 m to 50 m apart from a central red rice plant, assumed as the pollen donor. One hundred twenty rice CR plants, cv. BR-Irga 409, were planted in the intersections of the concentric circles and the twelve radii. From 51 SSR markers, four were selected due to their capacity to detect the polymorphism between RR and CR, aiming to identify RR alleles in seeds produced by BR-Irga 409 plants. The maximum distance found for gene flow between RR and CR plants was 10 m from the RR plant. In theory, at 0.1% cross pollination rate, this distance can generate 4,710 hybrids between RR and CR. In the next generation, about 3,532 plants would produce exclusively rice grains with red color. The SSR markers were able to identify the gene flow between RR and CR; therefore, they can be useful to increase the precision of cross pollination rate estimates in rice, mainly if used with other methodologies (e.g., herbicide tolerant plants). KEY WORDS: Cross pollination; microsatellite markers; Oryza sativa. Este trabalho objetivou avaliar a capacidade de marcadores SSR em detectar a ocorrência de fluxo gênico entre o arroz vermelho (AV) e o arroz cultivado (AC). Marcadores SSR são utilizados em análise genômica de plantas devido ao alto conteúdo informativo, serem co-dominantes e baseados na reação de PCR. O ensaio de campo foi realizado em dez círculos concêntricos de 5 m a 50 m de distância, a partir de uma planta AV central, que foi a fonte doadora de pólen. Foram semeadas 120 plantas de arroz da cultivar BR-Irga 409, distribuídas nas interseções entre os círculos e doze raios. A partir de 51 marcadores SSR, foram selecionados quatro marcadores que detectaram polimorfismo entre o AV e AC, para identificar os alelos de AV em sementes produzidas pelas plantas da cultivar BR-Irga 409. A distância máxima encontrada entre a planta AV doadora de pólen e uma planta AC que produziu sementes híbridas (AV x AC) foi de 10 m. Teoricamente, sob 0,1% de taxa de cruzamento, esta distância de polinização pode dar origem a 4.710 sementes híbridas entre AC e AV, o que, na geração seguinte, resultará em 3.532 plantas produzindo grãos vermelhos. Marcadores SSR foram capazes de identificar fluxo gênico entre AR e AC; e, portanto, podem ser empregados em associação com outras metodologias (ex. plantas tolerantes a herbicidas) para melhorar a precisão das estimativas de polinização cruzada em arroz. PALAVRAS-CHAVE: Oryza sativa; polinização cruzada; marcadores microssatélites.

Rice is one of the staple foods consumed worldwide, and rice breeding programs have become important to warrant high yield levels and grain quality in upland rice. This study aimed at insights on the genetic variability of 30 elite genotypes from a VCU trial, of the upland rice breeding program of Embrapa, using 25 SSR markers. One hundred and thirty- one alleles were obtained, an average of 5.2 alleles per locus, and mean PIC equal to 0.61. The results indicated that genetically different elite parents from the breeding program and selection in segregating families have given rise to broad- based rice genotypes. Analyzing different combinations of 10 SSR markers, we observed that the use of more informative markers is essential to explain the genetic divergence consistently with the pedigree of each rice genotype.

This study aimed to identify allele sources for seedling vigor in 65 rice genotypes, using the slantboard test in a germination chamber, and to determine the best parameter for evaluating seedling vigor. The experiment was arranged in the randomized block design with three replicate blocks. Root and primary leaf length data were collected from seedlings grown in the dark at 18 oC, 15 days after sowing and at 25 oC, ten days after sowing. The best performing genotypes for seedling vigor were included in Group 2, which contained red rice accessions. The vigor was best evaluated under controlled conditions (grown at 18 oC, 15 days after sowing) through measurements of roots and primary leaves.

The use of genetic resources for rice has been suggested as the most relevant alternative to raise the productivity levels achieved by modern cultivars (Brondani et al. 2003). However, before using these resources, it is fundamental to compile in depth knowledge on the existing genetic variability in these accessions to identify genotypes that could ultimately contribute effectively to genetic gains for traits of interest in rice breeding programs. It is estimated that over 200.000 accessions are stored in rice germplasm banks all over the

Wild rice of the species Oryza glumaepatula is found Brazil and has been used to broaden the genetic basis of irrigated rice populations in Embrapa breeding programs. Objective of this study was to demonstrate and discuss approaches used in the development of Oryza sativa lines containing genes transferred from Oryza glumaepatula, resulting in introgression lines with a broader genetic basis and high yield. First of all, genes were transferred from the wild species to cultivated ric e by the AB-QTL methodology. Eighteen families were selected using QTL analysis and agronomical performance data. After the heterosis test the families CNAi 9020 and CNAi 9024 were selected and submitted to microsatellite marker-assisted selection. Thirty-five lines were then selected with high plant vigor, high tiller and panicle number per plant, high grain yie ld of the main crop, and a strong regrowth capacity which makes the use of ratoons a feasible alternative.

The mapping population consisted of 94 F 2 generation plants derived from a cross between the CNFC 7812 and CNFC 8056 lines, with different protein contents, 24% and 19% respectively. Seven hundred and fifty-two molecular markers were tested among the parents and four individuals from the segregant population. A total of 101 loci were used to develop the genetic map. The polymorphism rate was 8.3% and 23.2% for the microsatellite and RAPD markers, respectively. The sizes of the linkage groups ranged from 6.7 to 139.0 cM , presenting a mean of 49.4 ± 36.8. The map length was 840.7 cM and the mean group length was 45.9 cM. The average distance between the framework loci was 16.1 cM. This map was compared with international reference bean maps and results were discussed. The construction of the genetic map from parents of the same center of origin and the commercial grain type were discussed. Made available in DSpace on 2011-04-09T14:42:25Z (GMT). No. of bitstreams: 1 CBABv10.pdf: 150953 bytes, checksum: d92528f695146dfbce6985a2ea995588 (MD5) Previous issue date: 2010-08-04

Conservation of microsatellite loci, heterozygous in Eucalyptus grandis, Eucalyptus urophylla, Eucalyptus tereticornis and Eucalyptus globulus, allowed us to propose homeologies among genetic linkage groups in these species, supported by at least three SSR loci in two different linkage groups. Marker-trait associations for sprouting and adventitious rooting ability were also compared in the four species. Putative quantitative trait loci (QTLs) influencing vegetative propagation traits were located on homeologous linkage groups. Our findings indicate high transferability of microsatellite markers between Eucalyptus species of the Symphyomyrtus subgenus and establish foundations for the use of synteny in the genetic analysis of this genus. Microsatellite markers should help integrate eucalypt genetic linkage maps from various sources. The availability of comparative linkage maps provides a basis of more-efficient use of genetic information for molecular breeding and evolutionary studies in Eucalyptus.

In this work we report the development and characterization of 10 microsatellite loci for the endangered tree species Caryocar brasiliense. Using genomic library enrichment, the efficiency of SSR marker development was 14.4% from sequencing data to operationally useful loci. Primer sequences for this set of 10 loci are made available together with their estimates of expected heterozygosity, probability of paternity exclusion and probability of identity. Mendelian inheritance and segregation was confirmed for all 10 loci in open-pollinated half-sib families as well as the absolute transferability of these 10 loci to five other species of the same genus. Number of alleles per locus ranged from 10 to 22 with a mean value of 16 and expected heterozygosity varying from 0.84 to 0.94. The combined probability of genetic identity was on the order of 10–17 clearly demonstrating that SSR multilocus genotypes are likely to be unique and capable of readily discriminating individuals of C. brasiliense. The very high combined probability of paternity exclusion (0.99999995) also indicates that these markers will permit detailed parentage studies in natural populations even in situations where both maternity and paternity are unknown. The battery of microsatellite markers developed and characterized in this study opens a new perspective for the generation of fundamental population genetic data for devising sound collection and conservation procedures for C. brasiliense and related species of the genus.

Caesalpinia echinata, commonly known as Pau-brasil (Brazilwood), the famous tree that named Brazil is native to the Atlantic forest. Men extensively exploited it ever since discovery and colonial times due to its value as a source of red dye. As a consequence, Brazilwood is a threatened species with populations reduced to small forest fragments. Ten polymorphic microsatellite loci were developed from an enriched genomic library. Using fluorescently-labeled primers, a total of 83 alleles were found after analyzing a sample of 44 trees. These high genetic information content markers should allow detailed investigations of mating systems, gene flow, population structure and paternity in natural populations.

Made available in DSpace on 2016-10-10T03:52:26Z (GMT). No. of bitstreams: 5 Development characterization and mapping of microsatellite markers in Eucalyptus grandis and E. urophylla.pdf: 434857 bytes, checksum: 624437860a7984c288a5560f141a4b16 (MD5) license_url: 52 bytes, checksum: 2f32edb9c19a57e928372a33fd08dba5 (MD5) license_text: 24372 bytes, checksum: 94b0a37ff5ec51de8c55507bff4a7ff9 (MD5) license_rdf: 24623 bytes, checksum: 378d22d8fe50e084ee2f354be78cbe62 (MD5) license.txt: 1887 bytes, checksum: 445d1980f282ec865917de35a4c622f6 (MD5) Previous issue date: 1998 We report on the development, genetic characterization and linkage mapping of a battery of SSR (simple sequence repeat) loci in Eucalyptus grandis and E. urophylla. This study reveals the abundance of SSRs in Eucalyptus, the very high information content of these markers for mapping and individual identiÞcation, and demonstrates the feasibility of constructing a comprehensive microsatellite-based linkage map for Eucalyptus. Primer sequence for a set of 20 highly informative EMBRA (Eucalyptus microsatellites from Brazil) loci are made available together with their map position and estimates of the expected heterozygosity and allele size range in these two species. Using genomic library enrichment and anchored-PCR screening prior to sequencing, the e¦ciency of SSR marker locus development was 63% from sequencing data to operationally useful SSR loci. Absolute transportability between the two species and very high levels of allelic variability and expected heterozygosity (H) were seen at all SSR loci surveyed. The number of alleles per locus ranged from 9 to 26 with an average of 16.3$4.8. The average H of 15 loci was 0.86$0.04, 0.83$0.08 and 0.89$0.04, respectively, for E. urophylla, E. grandis and the combined two-species estimate. In the mapping analysis 16 out of 20 marker loci segregated in a fully informative conÞguration, allowing the determination of synteny of six homologous linkage groups between the two species. The availability of transportable, multiallelic, PCR-based co-dominant SSR locirepresents a dramatic improvement in our ability to carry out detailed population genetic analysis and to search, understand, and manipulate allelic variation at QTLs (quantitative trait loci) in species of Eucalyptus. Sim Publicado

Efforts to develop molecular tools for genetic analysis and breeding of common bean in the tropics are still limited. The number of microsatellite markers available for the crop is small compared to other crops of similar social and economic importance. As part of a project to broaden the use of molecular tools in bean breeding, a genomic library enriched for AG/TC repeat sequences was constructed for Phaseolus vulgaris. Twenty microsatellite markers were initially developed and 10 were characterized using a panel of 85 representative accessions of the bean gene bank. The number of alleles per marker ranged from three to 10. The polymorphism information content (PIC) varied from 0.23 to 0.80. The results indicate that the new markers can be readily used in genetically analysis of common bean.

The new world screw-worm, Cochliomyia hominivorax, is one of the most important parasitic insect pests. This species causes myiasis and, consequently, significant losses to livestock industries in neotropical regions. As part of an investigation into the genetic variability and population structure of the new world screw-worm, a set of 10 polymorphic microsatellite markers was isolated from an AC-enriched genomic library. Amplification of the reported loci in 30 screw-worms revealed an average of 6.9 alleles per locus with expected heterozygosities ranging from 0.3831 to 0.8022. Cross-species amplifications suggested that these loci may be useful in other Calliphoridae species.

From a genomic library enriched for AG/TC repeats, eight polymorphic microsatellite markers were developed for Ceiba pentandra, a pan-tropical forest tree. Polymorphism was evaluated using a panel of 74 adult trees. Using automated fluorescence detection, a total of 112 alleles was detected with an average of 14 alleles per locus. All microsatellite loci showed very high levels of genetic information content, with expected heterozygosity ranging from 0.814 to 0.895. These microsatellite markers represent a powerful tool to investigate refined questions of mating systems, gene flow, family structure and population dynamics in natural populations of C. pentandra.

Euterpe edulis is the species of palm found in the Atlantic Forest and Cerrado gallery forest that yields the best heart of palm. A battery of 18 highly polymorphic microsatellite markers was developed from an enriched genomic library. Using fluorescence automated detection an average of 10.6 alleles per locus were found on a sample of 66 individuals sampled from a natural population. These loci allow extremely precise paternity testing, estimation of gene flow and of parentage coefficients among trees in the wild.

The objective of this study was to evaluate the genetic variability of rice (Oryza sativa) landraces collected in Brazilian small farms. Twelve simple sequence repeat (SSR) markers characterized 417 landraces collected in 1986, 1987 and 2003, in the state of Goiás, Brazil. The number of landraces with long and thin grain type increased in the evaluated period, probably due to market demand. Based on the molecular data, the genetic variability increased during this period and, as per to the factorial correspondence analysis, most of the accessions were grouped according to the year of collection. The incorporation of modern rice cultivars in landrace cultivation areas and the selection carried out by small farmers are the most probable factors responsible for increasing landrace genetic variability, during the evaluated period. Genotype exchange between farmers, selection practice and local environmental adaptation are able to generate novel adapted allele combinations, which can be used by breeding programs, to reinitiate the process. O objetivo deste trabalho foi avaliar a variabilidade genética de variedades locais de arroz (Oryza sativa), coletadas em pequenas propriedades rurais. Doze marcadores microssatélites (SSR) caracterizaram 417 variedades locais, coletadas em 1986, 1987 e 2003, no Estado de Goiás. O número de variedades locais com tipo de grão longo e fino aumentou no intervalo de tempo avaliado, provavelmente em razão da demanda de mercado. Conforme os dados moleculares, houve aumento na variabilidade genética e, por meio da análise fatorial de correspondência, observou-se que a maior parte dos acessos foi agrupada de acordo com o ano de coleta. A incorporação de cultivares modernas de arroz às áreas de cultivo das variedades locais e a seleção realizada pelos pequenos agricultores são, provavelmente, os fatores responsáveis pelo aumento observado na variabilidade genética, ao longo do período avaliado. O intercâmbio de genótipos entre fazendeiros, a prática da seleção e a adaptação ambiental ao local de cultivo são capazes de gerar novas combinações alélicas adaptadas que, por sua vez, podem ser usadas pelos programas de melhoramento, para reiniciar o processo.

The objectives of the present study were to monitor the effect of backcrossing through microsatellite markers and to compare different marker assisted selection strategies. Four populations were developed using donor parents resistant to the bean golden mosaic virus and, for all crosses, only individuals resistant to the bean golden mosaic virus were backcrossed. For crosses ARC100-4 x DOR303 and ARC100-4 x PHAS8328, assisted selection was carried out in the F(2) and F(2)BC(1) generations, while in the remaining crosses selection was performed only in the F(2)BC(1) generation. For the microsatellite analysis, in each generation, 20 markers were genotyped. The molecular data were analyzed using the NTSys program and the proportion of the recurrent genome introgressed was estimated, based on genotypical configuration of the segregant populations compared to the recurrent parents. The results indicate a higher efficiency in recovering the genotype of the elite genitor through the strategy of backcross assisted selection in the successive generations, and demonstrate a practical and useful application of molecular marker technology associated with bean breeding, to reduce the number of backcrosses and the time to recover the genome of the recurrent genitors.

The objectives of this study were to determine the genetic structure of 242 accessions from the EMBRAPA Rice Core Collection (ERiCC), to create a mini-core collection and to develop a multiplex panel of fluorescent labeled simple sequence repeats (SSRs). Eighty-six SSRs were used to identify 1,066 alleles, with an average number of 12.4 alleles/locus and average polymorphism information content (PIC)/locus of 0.75. A model-based clustering method recognized the structure of the accessions on two levels, according to their cultivation system and origin. The most divergent subgroup identified was the worldwide lowland accessions, with the highest values for gene diversity (0.75), average Rogers distance modified by Wright (0.80), average number of alleles/locus (11.7) and private alleles (132). A mini-core was assembled with the most divergent 24 lowland and upland accessions. This mini-core displayed an average distance of 0.86, an average number of alleles/locus of 8.4 and an average PIC/locus of 0.8. From the 86 SSRs, 24 were selected to compose six multiplex panels in order to optimize the process of rice genotyping. This set of markers distinguished all 242 accessions, and showed an average PIC of 0.80 and an average number of alleles/locus of 15.4, higher than the entire set of 86 SSRs. Since the heterogeneity found in lines and cultivars of ERiCC was higher than expected, it is necessary to analyze pooled DNA samples to get a better estimate of genetic variability. The SSR characterization of ERiCC clearly indicates that there is high genetic variability in rice accessions stored in genebanks worldwide which can be promptly explored by rice pre-breeding programs.

Common bean is grown and consumed principally in developing countries in Latin America, Africa, and Asia. It is largely a subsistence crop eaten by its producers and, hence, is underestimated in production and commerce statistics. Common bean is a major source of dietary protein, which complements carbohydrate-rich sources such as rice, maize, and cassava. It is also a rich source of minerals, such as iron and zinc, and certain vitamins. Several large germplasm collections have been established, which contain large amounts of genetic diversity, including the five domesticated Phaseolus species and wild species, as well as an incipient stock collection. The genealogy and genetic diversity of P. vulgaris are among the best known in crop species through the systematic use of molecular markers, from seed proteins and isozymes to simple sequence repeats, and DNA sequences. Common bean exhibits a high level of genetic diversity, compared with other selfing species. A hierarchical organization into gene pools and ecogeographic races has been established. There are over 15 mapping populations that have been established to study the inheritance of agronomic traits in different locations. Most linkage maps have been correlated with the core map established in the BAT93 x Jalo EEP558 cross, which includes several hundreds of markers, including Restriction Fragment Length Polymorphisms, Random Amplified Polymorphic DNA, Amplified Fragment Length Polymorphisms, Short Sequence Repeats, Sequence Tagged Sites, and Target Region Amplification Polymorphisms. Over 30 individual genes for disease resistance and some 30 Quantitative Trait Loci for a broad range of agronomic traits have been tagged. Eleven BAC libraries have been developed in genotypes that represent key steps in the evolution before and after domestication of common bean, a unique resource among crops. Fluorescence in situ hybridization provides the first links between chromosomal and genetic maps. A gene index based on some P. vulgaris 21,000 expressed sequence tags (ESTs) has been developed. ESTs were developed from different genotypes, organs, and physiological conditions. They resolve currently in some 6,500–6,800 singletons and 2,900 contigs. An additional 20,000 embryonic P. coccineus ESTs provides an additional resource. Some 1,500 M2 Targeting Local Lesions In Genomes populations exist currently. Finally, transformation methods by biolistics and Agrobacterium have been developed, which can be applied for genetic engineering. Root transformation via A. rhizogenes is also possible. Thus, the Phaseomics community has laid a solid foundation towards its ultimate goal, namely the sequencing of the Phaseolus genome. These genomic resources are a much-needed source of additional markers of known map location for marker-assisted selection and the accelerated improvement of common bean cultivars.

This study aimed to present and discuss the recurrent selection methodology used in the development of the rice cultivar SCSBRS Tio Taka. This cultivar, derived from the population CNA-IRAT 4, achieves high yields and has agronomic traits related to a better performance in the pre-germinated cultivation system used in Santa Catarina State. The molecular characterization of Tio Taka and CNA-IRAT 4 parents with 16 SSR markers showed that one of the parents, BG 90-2, was highly similar to SCSBRS Tio Taka. The most probable reason was that SCSBRS Tio Taka was extracted from CNA-IRAT 4 in the second recombination cycle, preventing the ccurrence of a high level of recombination and favoring the phenotypic selection of plants derived from crosses with BG 90-2 as parent, once this line has one of the best plant architectures and yields.

The rice (Oryza sativa) breeding program of the Rice and Bean research center of the Brazilian agricultural company Empresa Brasileira de Pesquisa Agropecuária (Embrapa) is well established and provides new cultivars every year to attend the demand for improved high yielding varieties with tolerance to biotic and abiotic stresses. However, the elite genitors used to compose new populations for selection are closely related, contributing to the yield plateau reached in the last 20 years. To overcome this limit, it is necessary to broaden the genetic basis of the cultivars using diverse germplasm such as wild relatives or traditional varieties, with the latter being more practical because they are more easily crossed with elite germplasm to accelerate the recovery of modern plant types in the breeding lines. The objective of our study was to characterize the allelic diversity of 192 traditional varieties of Brazilian rice using 12 simple sequence repeat (SSR or microsatellite) markers. The germplasm was divided into 39 groups by common name similarity. A total of 176 alleles were detected, 30 of which (from 23 accessions) were exclusive. The number of alleles per marker ranged from 6 to 22, with an average of 14.6 alleles per locus. We identified 16 accessions as a mixture of pure lines or heterozygous plants. Dendrogram analysis identified six clusters of identical accessions with different common names and just one cluster with identical accessions with the same common name, indicating that SSR markers are fundamental to determining the genetic relationship between landraces. A subset of 24 landraces, representatives of the 13 similarity groups plus the 11 accessions not grouped, was the most variable set of genotypes analyzed. These accessions can be used as genitors to increase the genetic variability available to rice breeding programs. Made available in DSpace on 2017-11-16T23:22:34Z (GMT). No. of bitstreams: 1 CNPAF2006cb.pdf: 155864 bytes, checksum: ffd86dc387ebba5704fb19aaec91565a (MD5) Previous issue date: 2006-11-06

The existence of Oryza glumaepatula is threatened by devastation and, thus, the implementation of conservation strategies is extremely relevant. This study aimed to characterize the genetic variability and estimate population parameters of 30 O. glumaepatula populations from three Brazilian biomes using 10 microsatellite markers. The levels of allelic variability for the SSR loci presented a mean of 10.3 alleles per locus and a value of 0.10 for the average allelic frequency value. The expected total heterozygosity (H(e)) ranged from 0.63 to 0.86. For the 30 populations tested, the mean observed (H(o)) and expected heterozygosities (H(e)) were 0.03 and 0.11 within population, respectively, indicating an excess of homozygotes resulting from the preferentially self-pollinating reproduction habit. The estimated fixation index ( (IS) ) was 0.79 that differed significantly from zero, indicating high inbreeding within each O. glumaepatula population. The total inbreeding of the species ((IT) ) was 0.98 and the genetic diversity indexes among populations, (ST) and (ST), were 0.85 and 0.90, respectively, indicating high genetic variability among them. Thus, especially for populations located in regions threatened with devastation, it is urgent that in situ preservation conditions should be created or that collections be made for ex situ preservation to prevent loss of the species genetic variability.

The genus Oryza comprises 22 species which are potentially useful as a source of genetic variability that can be introgressed into the worldwide cultivated rice, Oryza sativa. Molecular markers are useful tools for monitoring gene introgressions and for detecting polymorphism among species. In this study, cross-amplification was estimated among 28 accessions of 16 Oryza species, representing the genomes AA, BB, CC, BBCC and CCDD, using 59 microsatellite (OG, OS and RM series) and 15 STS (Sequence Tagged Sites) markers. All markers amplified at least one Oryza species, indicating different levels of transferability across species. Markers based on microsatellite sequences amplified 37 % of the accessions, with an average of 6.58 alleles per locus and an average polymorphism information content (PIC) of 70 %. For STS markers, the amplification level was 53.3 %, and the average number of alleles and PIC values were 1.6 and 10 %, respectively. These Results showed that although the STS markers detected a reduced level of genetic diversity, the transferability was higher, indicating that they can be used for genetic analysis when evaluating less genetically related species of Oryza. Among the microsatellite markers, an analysis of species with an AA genome showed that the OG markers produced the highest level of polymorphic loci (54.6 %), followed by RM markers (48 %). Highly polymorphic and transferable molecular markers in Oryza can be useful for exploiting the genetic resources of this genus, for detecting allelic variants in loci associated with important agronomic traits, and for monitoring alleles introgressed from wild relatives to cultivated rice.

The ''cagaita tree'' (Eugenia dysenterica) is a plant found widespread in the Brazilian Cerrado. Its fruit is used for popular consumption and for industrial purposes. This study opens a new perspective for the generation of population genetic data and parameters estimates for devising sound collection and conservation procedures for Eugenia dysenterica. A battery of 356 primer pairs developed for Eucalyptus spp. was tested on the ''cagaita tree''. Only 10 primer pairs were found to be transferable between the two species. Using a polyacrilamide gel, an average of 10.4 alleles per locus was detected, in a sample of 116 individuals from 10 natural ''cagaita tree'' populations. Seven polymorphic loci allowed estimation of genetic parameters, including expected average heterozygosity He = 0,442, among population diversity, RST = 0,268 and gene flow Nm = 0,680. Results indicated a potential of SSR locus transferability developed for Eucalyptus to other species of different genera, such as in the case of the ''cagaita tree''. The high genetic diversity among populations detected with SSR markers indicated that these markers are highly sensitive to detect population structure. Estimated Nm values and the existence of private alleles indicated reduced gene flow and consequently possible damage to the metapopulation structure. Made available in DSpace on 2020-05-05T04:39:47Z (GMT). No. of bitstreams: 1 CNPAF-2003-gmb.pdf: 338713 bytes, checksum: 2671ac248e5bee5e383d296465041bf1 (MD5) Previous issue date: 2003

Wild germplasm of domesticated crops is a source of genetic variation little utilized in breeding programs. Interspecific crosses can potentially uncover novel gene combinations that can be important for quantitative trait analysis. The combined use of wide crosses and genetic maps of chromosomal regions associated with quantitative traits can be used to broaden the genetic basis of rice breeding programs. Oryza glumaepatula is a diploid (AA genome) wild rice species native from South and Central America. A genetic map was constructed with 162 PCR-based markers (155 microsatellite and 7 STS markers) using a backcross population derived from the cross O. glumaepatula, accession RS-16 from the Brazilian Amazon Region x O. sativa BG-90-2, an elite rice inbred line. The map included 47 new SSR markers developed from an O. glumaepatula genomic library enriched for AG/TC sequences. All SSR markers were able to amplify the O. sativa genome, indicating a high degree of SSR flanking region conservation between O. glumaepatula and O. sativa species. The map covered 1500.4 cM, with an average of one marker every 10 cM. Despite some chromosomes being more densely mapped, the overall coverage was similar to other maps developed for rice. The advantage to construct a SSR-based map is to permit the combination of the speed of the PCR reaction, and the codominant nature of the SSR marker, facilitating the QTL analysis and marker assisted selection for rice breeding programs.

Rice ( Oryza sativa) cultivar development currently faces the task of overcoming yield plateaus, which is difficult due to the narrow genetic base of breeding programs. Oryza glumaepatula is a diploid wild relative of cultivated rice, native to Central and South America, and is therefore a potential source of alleles of agronomic importance to rice breeding programs. We studied 11 agronomic traits in BC(2)F(2) families of the interspecific cross Oryza sativa x O. glumaepatula. Transgressive lines which are almost isogenic to the elite recurrent O. sativa parent were identified for most of these traits. Quantitative trait locus (QTL) analysis was performed by single-point and interval mapping using a molecular map based on 157 microsatellite and STS markers. Marker regions accounting for 14.5 to 72.9% of a phenotypic variation trait were identified in 9 of the 12 rice chromosomes. Positive QTL effects from O. glumaepatula were observed in chromosomal regions associated with tillering and panicle-number traits.

An AG microsatellite-enriched genomic DNA library was constructed for Magnaporthe grisea (anamorph Pyricularia grisea), the causal agent of rice blast. Seventy-two DNA clones containing microsatellite repeats were isolated and sequenced in order to develop a series of new PCR-based molecular markers to be used in genetic studies of the fungus. Twenty-four of these clones were selected to design primer pairs for the PCR amplification of microsatellite alleles. Single spore cultures of M. grisea isolated from rice and wheat in Brazil, Colombia and China were genotyped at three microsatellite loci. Isolates from southern Brazil were predominantly monomorphic at the tested SSR loci, indicating a low level of genetic variability in these samples. However, seven alleles were observed at the MGM-1 locus in isolates from Central Brazil and at least nine alleles were detected at the same locus in a sample of Colombian isolates. Polymorphism analysis at SSR loci is a simple and direct approach for estimating the genetic diversity of M. grisea isolates and a powerful tool for studying M. grisea genetics. Uma biblioteca genômica enriquecida para seqüências microssatélites foi construída para Magnaporthe grisea (anamorfo Pyricularia grisea), o agente causal da doença brusone do arroz. Setenta e dois clones de DNA contendo unidades repetitivas microssatélites foram isolados e seqüenciados para o desenvolvimento de uma série de novos marcadores moleculares baseados em reação de PCR, para serem utilizados na análise genética do fungo. Dos 72 clones, 24 foram selecionados para o desenho dos pares de primers para amplificação dos alelos microssatélites pela técnica de PCR. Culturas monospóricas de M. grisea isoladas de plantas de arroz e trigo no Brasil, Colômbia e China foram genotipadas utilizando-se 3 locos microssatélites. Isolados do fungo provenientes do Estado do Rio Grande do Sul foram predominantemente monomórficos nos locos microssatélites testados, indicando um baixo nível de variabilidade genética destas amostras. Contudo, 7 alelos puderam ser detectados pelo marcador MGM-1 em isolados provenientes do Estado do Tocantins e no mínimo 9 alelos puderam ser detectados com o mesmo marcador em uma amostra de isolados da Colômbia. A análise com marcadores microssatélites é uma metodologia simples e direta para se estimar a diversidade genética dos isolados de M. grisea e uma poderosa ferramenta para o estudo da genética de M. grisea.

Cagaita (Eugenia dysenterica) is a widespread plant found in the Brazilian cerrado. Its fruit is used for popular consumption and for industrial purposes. A battery of 346 primer pairs developed for Eucalyptus spp. was tested on cagaita. Only 10 primer pairs were found to be transferable between the two species. Using a polyacrilamide gel, an average of 10.4 alleles per locus was detected, in a sample of 116 individuals from 10 natural populations of cagaita. Seven polymorphic loci allowed estimation of genetic parameters, including expected average heterozigosity HE = 0.442, diversity among populations, RST = 0.268 and gene flow Nm = 0.680.

Background Over recent years, a growing effort has been made to develop microsatellite markers for the genomic analysis of the common bean (Phaseolus vulgaris) to broaden the knowledge of the molecular genetic basis of this species. The availability of large sets of expressed sequence tags (ESTs) in public databases has given rise to an expedient approach for the identification of SSRs (Simple Sequence Repeats), specifically EST-derived SSRs. In the present work, a battery of new microsatellite markers was obtained from a search of the Phaseolus vulgaris EST database. The diversity, degree of transferability and polymorphism of these markers were tested. Results From 9,583 valid ESTs, 4,764 had microsatellite motifs, from which 377 were used to design primers, and 302 (80.11%) showed good amplification quality. To analyze transferability, a group of 167 SSRs were tested, and the results showed that they were 82% transferable across at least one species. The highest amplification rates were observed between the species from the Phaseolus (63.7%), Vigna (25.9%), Glycine (19.8%), Medicago (10.2%), Dipterix (6%) and Arachis (1.8%) genera. The average PIC (Polymorphism Information Content) varied from 0.53 for genomic SSRs to 0.47 for EST-SSRs, and the average number of alleles per locus was 4 and 3, respectively. Among the 315 newly tested SSRs in the BJ (BAT93 X Jalo EEP558) population, 24% (76) were polymorphic. The integration of these segregant loci into a framework map composed of 123 previously obtained SSR markers yielded a total of 199 segregant loci, of which 182 (91.5%) were mapped to 14 linkage groups, resulting in a map length of 1,157 cM. Conclusions A total of 302 newly developed EST-SSR markers, showing good amplification quality, are available for the genetic analysis of Phaseolus vulgaris. These markers showed satisfactory rates of transferability, especially between species that have great economic and genomic values. Their diversity was comparable to genomic SSRs, and they were incorporated in the common bean reference genetic map, which constitutes an important contribution to and advance in Phaseolus vulgaris genomic research.

We used microsatellite loci to test the paternity of two male jaguars involved in an infanticide event recorded during a long-term monitoring program of this species. Seven microsatellite primers originally developed for domestic cats and previously selected for Panthera oncawere used. In order to deal with uncertainty in the mother?s genotypes for some of the loci, 10000 values of Wwere derived by simulation procedures. The male that killed the two cubs was assigned as the true sire. Although the reasons for this behavior remain obscure, it shows, in principle, a low recognition of paternity and kinship in the species. Since the two cubs were not very young, one possibility is that the adult male did not recognize the cubs and killed them for simple territorial reasons. Thus, ecological stress in this local population becomes a very plausible explanation for this infanticide, without further sociobiological implications. Made available in DSpace on 2017-11-16T23:22:46Z (GMT). No. of bitstreams: 1 CNPAF2006gmb.pdf: 173013 bytes, checksum: f85956119011e6bb9c4b7994370bc3e0 (MD5) Previous issue date: 2007-01-10

The objective of this study was to identify molecular markers linked to the rust resistance gene or genes present in PI 260418. These markers will be very useful in the introgression of this new resistance into dry and snap bean cultivars. Made available in DSpace on 2018-05-30T00:51:36Z (GMT). No. of bitstreams: 1 SP19610ID30888.pdf: 387121 bytes, checksum: 58de9343e9659e7785e9f52406732885 (MD5) Previous issue date: 2009-02-02

No presente trabalho, a metodologia NBS-profiling foi utilizada para o desenvolvimento de marcadores RGA (Resistance Genes Analogs) em duas populações de Phaseolus vulgaris, sendo uma derivada do cruzamento entre Bat 93 e Jalo EEP558 (BJ) e a outra derivada do cruzamento entre Carioca e Flor de Mayo (CFM). Uma vez identificados, foram mapeados 32 marcadores RGA na população BJ e 40 na população CFM. Nove dos marcadores alocados no mapa de ligação da população BJ se localizaram em proximidade a clusters de resistência, já identificados por outros pesquisadores. Foi realizado o sequenciamento de 32 dos RGA detectados, sendo 16 da cada população. Cinco sequências oriundas da população BJ e três sequências da população CFM apresentaram similaridade com proteínas de resistência identificadas em P. vulgaris, Glycine max e Medicago truncaluta. O mapa de ligação aqui gerado para a população CFM foi utilizado para o posicionamento de QTL (Quantitative Trait Loci) de resistência à mancha-angular (Pseudocercospora griseola (Sacc.) Crous & Braun) e ao oídio (Erysiphe polygoni DC.). Um total de 12 QTL foi mapeado, cinco associados à resposta à mancha angular e sete à resposta ao oídio. In the presenty study, the NBS-profiling method was used for the development of RGA (Resistance Gene Analogs) markers in two populations of Phaseolus vulgaris, one derived from a cross between \'Bat 93\' and \'Jalo EEP558\' (BJ) and the other derived from a cross between \'Carioca\' and \'Flor de Mayo (CFM). After their identification, 32 RGA markers were mapped on the BJ population and 40 on the CFM population. Nine of the markers assigned to the linkage map of the BJ population were located in the proximity to clusters of resistance already identified by other researchers. We carried out the sequencing of 32 out of the RGA detected, being 16 from each population. Five sequences derived from the BJ population and three sequences from the CFM population showed similarity to resistance proteins identified in P. vulgaris, Glycine max and Medicago truncaluta. The linkage map here generated for the CFM population was used for the positioning of QTL (Quantitative Trait Loci) for resistance to angular leaf spot (Pseudocercospora griseola (Sacc.) Crous & Braun) and powdery mildew (Erysiphe polygoni DC.). Twelve QTL were mapped, five associated to the response to the angular leaf spot and seven to the powdery mildew.

O objetivo deste trabalho foi determinar o potencial produtivo e a interação entre genótipos e ambientes em 550 acessos da Coleção Nuclear de Arroz da Embrapa. O desempenho, a adaptação e a estabilidade produtiva de cada genótipo foram avaliados por meio da metodologia de análise dos efeitos principais aditivos e interações multiplicativas (AMMI), em nove experimentos de campo, realizados em seis Estados, em condição de sequeiro e irrigada, durante três anos agrícolas. Foi realizada a análise por meio de modelos lineares mistos, e as estimativas de componentes de variância foram obtidas pelo método de máxima verossimilhança residual (REML), com aplicação do procedimento de melhor predição linear não viesada (BLUP) para a predição dos valores genéticos dos efeitos aleatórios (EBLUP) associados a cada um dos acessos. O grupo de acessos com melhor desempenho foi o de linhagens e cultivares brasileiras (LCB), conforme o esperado. No entanto, foram identificadas variedades tradicionais (VT) entre os genótipos mais produtivos, o que mostra o potencial deste grupo de germoplasma em contribuir com novas fontes de variabilidade genética para programas de melhoramento. Foram identificados acessos superiores quanto à estabilidade, adaptabilidade e produtividade de grãos, entre os quais destacam-se CA880078, CA840182 e CNA00091.

Background: Over recent years, a growing effort has been made to develop microsatellite markers for the genomic analysis of the common bean (Phaseolus vulgaris) to broaden the knowledge of the molecular genetic basis of this species. The availability of large sets of expressed sequence tags (ESTs) in public databases has given rise to an expedient approach for the identification of SSRs (Simple Sequence Repeats), specifically EST-derived SSRs. In the present work, a battery of new microsatellite markers was obtained from a search of the Phaseolus vulgaris EST database. The diversity, degree of transferability and polymorphism of these markers were tested. Results: From 9,583 valid ESTs, 4,764 had microsatellite motifs, from which 377 were used to design primers, and 302 (80.11%) showed good amplification quality. To analyze transferability, a group of 167 SSRs were tested, and the results showed that they were 82% transferable across at least one species. The highest amplification rates were observed between the species from the Phaseolus (63.7%), Vigna (25.9%), Glycine (19.8%), Medicago (10.2%), Dipterix (6%) and Arachis (1.8%) genera. The average PIC (Polymorphism Information Content) varied from 0.53 for genomic SSRs to 0.47 for EST-SSRs, and the average number of alleles per locus was 4 and 3, respectively. Among the 315 newly tested SSRs in the BJ (BAT93 X Jalo EEP558) population, 24% (76) were polymorphic. The integration of these segregant loci into a framework map composed of 123 previously obtained SSR markers yielded a total of 199 segregant loci, of which 182 (91.5%) were mapped to 14 linkage groups, resulting in a map length of 1,157 cM. Conclusions: A total of 302 newly developed EST-SSR markers, showing good amplification quality, are available for the genetic analysis of Phaseolus vulgaris. These markers showed satisfactory rates of transferability, especially between species that have great economic and genomic values. Their diversity was comparable to genomic SSRs, and they were incorporated in the common bean reference genetic map, which constitutes an important contribution to and advance in Phaseolus vulgaris genomic research.

We isolated and characterized 12 microsatellite loci for Tibouchina papyrus (Melastomataceae), an endangered species with narrow and disjunct range, endemics to a few localities in ?cerrado rupestre? from Central Brazil. These microsatellites were obtained by sequencing of a genomic shotgun library for primer design. Leaves from 96 individuals collected in the three known local populations were genotyped using the 12 primers designed to analyze the polymorphisms at each locus. The number of alleles per locus ranged from one to six; two loci were monomorphic. Among the polymorphic loci, expected heterozygosities ranged from 0.161 to 0.714. Combined paternity exclusion probability was 0.957 and combined genetic identity (0.051) was high for studies on parentage. Tibouchina papyrus is a rare and endemic tree species of outcrop quartzite and sandstone soils, with highly isolated populations, which may have lead to the low degree of polymorphism that we detected. Also, motifs of most loci are larger than dinucleotide, which typically display lower levels of polymorphism. Made available in DSpace on 2011-04-09T14:47:26Z (GMT). No. of bitstreams: 1 gmr.pdf: 283155 bytes, checksum: a4f24af854ccf7804dd2d5543280ff36 (MD5) Previous issue date: 2011-03-23

We identified 14 microsatellite loci for the wolf fish, Hoplias malabaricus (Erythrinidae), from a genomic shotgun library. Twenty-five primers were designed, and 48 individuals of H. malabaricus from four localities of northwest Goiás, in central Brazil, were genotyped to characterize the polymorphism at each locus. Fourteen primers amplified clearly interpretable products using a single PCR protocol; six loci were polymorphic, but with a low number of alleles per locus (2 or 3). Expected heterozygosities for polymorphic loci ranged from 0.136 to 0.505. Combined paternity exclusion probability (0.638) was low and combined genetic identity (0.056) was high in studies of parentage. The low polymorphism may be due to the small microsatellite size and the large size of the motifs. Made available in DSpace on 2021-01-10T09:03:47Z (GMT). No. of bitstreams: 1 GMR-2010.pdf: 217140 bytes, checksum: 2733b61f2f036ab07b350a2bc20e25ca (MD5) Previous issue date: 2010

We isolated and characterized 10 microsatellite loci in the armored catfish (Hypostomus gymnorhynchus, Loricariidae), using a genomic shotgun library to obtain the repetitive sequences. Twenty-four primers were designed and 14 individuals of H. gymnorhynchus from the Caiapó River, in central Brazil, were genotyped using these primers to analyze the polymorphism at each locus. All loci showed low polymorphism, with a low number of alleles per locus (1 or 2), except locus Hg_E19, which had 11 alleles. Expected heterozygosities for polymorphic loci ranged from 0.182 to 0.901. Combined paternity exclusion probability (0.857) was low and combined genetic identity (0.0026) was high, when we examined parentage. The low degree of polymorphism that we detected may be due to the small sample size and the small microsatellite size, despite the large motif size. Made available in DSpace on 2021-01-13T09:04:03Z (GMT). No. of bitstreams: 1 GMR-2010.pdf: 303538 bytes, checksum: 31b9520b9cb56280fb0a0c8833f1dd6e (MD5) Previous issue date: 2010