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Made available in DSpace on 2021-02-18T17:18:27Z (GMT). No. of bitstreams: 1 gmr18503-establishment-capsicum-frutescens-core-collections-based-morphological-and-molecular-0.pdf: 612456 bytes, checksum: 1818d144bb99c7f6e9c4e3f3e486afc9 (MD5) Previous issue date: 2020

A germplasm collection of C. frutescensis maintained at Embrapa Vegetables, Brasilia, Brazil, the branch for vegetable crops of the Brazilian Agricultural Research Corporation (EMBRAPA). This is considered to be the main collection representing the variability of this species in the country. Made available in DSpace on 2020-06-10T04:08:27Z (GMT). No. of bitstreams: 1 gmr18503-establishment-capsicum-frutescens-core-collections-based-morphological-and-molecular-0.pdf: 619588 bytes, checksum: f15010377a5db58899c57c89921786e2 (MD5) Previous issue date: 2020

Os recursos genéticos vegetais são definidos como parte essencial da biodiversidade, constituídos pela variabilidade genética presente em espécies de plantas de uso atual ou potencial em programas de melhoramento genético, biotecnologia e áreas afins.

The aim of this study was to evaluate the reaction of Habanero-type advanced inbred lines, developed by Embrapa Hortaliças breeding program, to RP and PC. Made available in DSpace on 2019-12-06T00:36:27Z (GMT). No. of bitstreams: 1 20193746.pdf: 1691906 bytes, checksum: 3905f1893691395212eb1a077c8617f2 (MD5) Previous issue date: 2019

Characterization studies provide essential information for the conservation and use of germplasm in plant breeding programs. In this study, 103 Capsicum frutescens L. accessions from the Active Germplasm Bank of Embrapa Hortaliças, representative of all five Brazilian geographic regions, were characterized based on morphological characteristics and microsatellite (or simple sequence repeat - SSR) molecular markers. Morphological characterization was carried out using 57 descriptors, and molecular characterization was based on 239 alleles from 24 microsatellite loci. From the estimates of genetic distances among accessions, based on molecular characterization, a cluster analysis was carried out, and a dendrogram was established. Correlations between morphological and molecular variables were also estimated. Twelve morphological descriptors were monomorphic for the set of C. frutescens accessions, and those with the highest degree of polymorphism were stem length (14.0 to 62.0 cm), stem diameter (1.0 to 4.2 cm), days to flowering (90 to 129), days to fruiting (100 to 140), fruit weight (0.1 to 1.4 g), fruit length (0.6 to 4.6 cm), and fruit wall thickness (0.25 to 1.5 mm). The polymorphism information content for the SSR loci varied from 0.36 (EPMS 417) to 0.75 (CA49), with an overall mean of 0.57. The correlation value between morphological and molecular characterization data was 0.6604, which was statistically significant. Fourteen accessions were described as belonging to the morphological type tabasco, 85 were described as malagueta, and four were malaguetinha, a morphological type confirmed in this study. The typical morphological pattern of malagueta was described. Six similarity groups were established for C. frutescens based on the dendrogram and are discussed individually. The genetic variability analyzed in the study highlights the importance of characterizing genetic resources available for the development of new C. frutescens cultivars with the potential for various niche markets. Made available in DSpace on 2017-11-16T23:25:39Z (GMT). No. of bitstreams: 1 GeneticsandMolecularResearchv.16n.32017.CARVALHOetal....pdf: 2088729 bytes, checksum: 20336912090689f13a87a443041c517c (MD5) Previous issue date: 2017-11-16

Germplasm banks are essential as sources of genetic variability for plant breeding programs. To characterize a Brazilian Capsicum frutescens collection, 21 malagueta and 5 Tabasco hot pepper accessions were evaluated under field and greenhouse conditions regarding morphological and molecular traits, as well as resistance to viruses. The incidence of viruses in field-grown plants varied among genotypes and according to virus species, from 5.6% (GRSV; CNPH 3286) to 100% (PMMoV; CNPH2871), and indicated some accessions as potential sources of virus resistance. These results demonstrate the genetic variability within the group of 26 hot pepper accessions, as well as virus-resistant genotypes that can be used in breeding programs. Made available in DSpace on 2017-10-07T10:32:00Z (GMT). No. of bitstreams: 1 gmr1603gmr.160397041.pdf: 1600341 bytes, checksum: 2eaaab25c7b013e53f7fa57c5fa4555b (MD5) Previous issue date: 2017-10-06

Resumo: As pimentas são parte da riqueza cultural e do valioso patrimônio genético da biodiversidade brasileira. O desenvolvimento de novas cultivares de pimentas e híbridos com características agronômicas e industriais de interesse depende da variabilidade disponível dos seus recursos genéticos. O objetivo geral desse trabalho foi realizar estudos filogenéticos e de diversidade genética em Capsicum utilizando marcadores moleculares e características morfológicas visando subsidiar ações de conservação e uso de recursos genéticos de C. frutescens e C. chinense em programas de melhoramento para o desenvolvimento de tipos varietais brasileiros como a pimenta malagueta. Os objetivos específicos foram: estudar a filogenia e a diversidade genética de Capsicum spp. com base em marcadores ISSR (Inter Simple Sequence Repeat) e características morfológicas relacionadas ao grau de domesticação; analisar a transferibilidade de primers microssatélites (SSR - Simple Sequence Repeats) de C. annuum para C. frutescens e C. chinense; confirmar a existência de híbridos naturais; caracterizar a coleção ativa de germoplasma de C. frutescens da Embrapa Hortaliças; estabelecer uma coleção nuclear de C. frutescens e comparar a coleção nuclear à população base do melhoramento. As ações de pesquisa foram realizadas na Embrapa Hortaliças, Embrapa Recursos Genéticos e Biotecnologia e Embrapa Cerrados, localizadas em Brasília, DF. Quatro acessos silvestres coletados na região Amazônica (CNPH 4315, CNPH 4325B, CNPH 4337 e CNPH 4372), popularmente conhecidos como olho-de-peixe ou olho-de periquito, foram caracterizados utilizando marcadores ISSR como C. chinense e apresentaram frutos com características típicas de espécie silvestre. O acesso silvestre CNPH 4353, conhecido como malaguetinha foi morfologicamente e molecularmente classificado como C. frutescens. É possível, ainda, que esses materiais coletados na Bacia Amazônica, considerada a maior área de diversidade de C. chinense, compartilhem das mesmas características morfológicas dos ancestrais silvestres dessa espécie. A transferibilidade de um conjunto de primers SSR de C. annuum foi testada para as espécies C. frutescens e C. chinense. Dos 185 primers SSR de C. annuum (CA) analisados, 116 (62,7%) apresentaram transferibilidade para as duas espécies. Destes, 19 (16,37%) apresentaram-se polimórficos com uma média de 2,89 alelos por loco para C. frutescens e 35 (30,17%) mostraram polimorfismo com uma média de 3,3 alelos por loco para C. chinense. Com base no estudo da transferibilidade, 17 primers CA podem ser utilizados para se analisar amostras constituídas por C. chinense e C. frutescens. Essas duas espécies são muito próximas geneticamente, sendo difícil a distinção dos acessos, principalmente considerando-se a possibilidade de ocorrência de híbridos naturais. Para confirmar a ocorrência de híbridos interespecíficos naturais, foram realizados testes de viabilidade polínica e compatibilidade genética, caracterização morfológica, caracterização molecular e teor de capsaicinóides. Os resultados mostraram que, embora as espécies C. chinense e C. frutescens apresentem similaridades e características compartilhadas com sobreposição de caracteres morfológicos, são de fato distintas pelas análises com marcadores SSR. Testes de viabilidade polínica e de compatibilidade genética mostraram CNPH 4325A e CNPH 4361 como resultados de hibridização natural, em especial o acesso CNPH 4361, que apresentou características morfológicas de ambas as espécies, posição intermediária tanto no dendrograma como no gráfico de dispersão na análise molecular, ocorrência de alelos em heterozigose em seis loci e conteúdo intermediário de capsaicina, de 154 mil SHU. A avaliação da variabilidade genética dos 115 acessos que compõem a coleção ativa de germoplasma de C. frutescens da Embrapa Hortaliças foi realizada com base em 57 características morfológicas e 239 alelos de 24 loci de marcadores SSR. Este estudo permitiu a formação de seis grupos de similaridade em cada uma das análises e mostrou que os acessos são divergentes, havendo variabilidade genética para desenvolvimento de cultivares de C. frutescens para diversos nichos como: comercialização in natura e produção de conservas e molhos. Os marcadores SSR demonstraram maior capacidade de discriminação em relação aos descritores morfológicos. A altura e a largura das plantas foram as variáveis que apresentaram maior contribuição no índice de diversidade genética. Foi possível o estabelecimento da coleção nuclear com 13 acessos de C. frutescens representando 77% da variabilidade genética da coleção ativa, utilizando-se 239 alelos de 24 loci de marcadores moleculares SSR, 57 características morfológicas e diferentes estratégias de seleção. A melhor estratégia para formação da coleção nuclear foi evidenciada pela seleção dos acessos nos diferentes grupos de similaridade estabelecidos por marcadores moleculares SSR e incidência de viroses. Características morfológicas e moleculares foram utilizadas para avaliar e comparar a variabilidade genética dessa coleção nuclear (13 acessos), de uma população base de melhoramento genético (6 acessos) e de uma coleção ativa (104 acessos) de C. frutescens. Verificou-se maior variabilidade genética entre os acessos da coleção nuclear em relação à população base, tanto na caracterização morfológica quanto na molecular. Os resultados demonstram que os acessos da coleção nuclear podem aumentar a base genética dos programas de melhoramento genético de C. frutescens, maximizando as possibilidades de combinações gênicas desejáveis. ABSTRACT: Peppers are part of the cultural wealth and of the valuable genetic patrimony of the Brazilian biodiversity. The development of new pepper cultivars and hybrids with agronomic and industrial traits of interest relies on the variability of the genetic resources available. The overall objective of this work was to study phylogenetics and genetic diversity in Capsicum using molecular markers as well as morphologic characteristics to subsidize conservation and use of genetic resources of C. frutescens and C. chinense in breeding programs for the development of Brazilian varietal types such as the malagueta pepper. The specific objectives were: to study phylogenetics and genetic diversity of Capsicum spp. based on ISSR (Inter Simple Sequence Repeat) markers and morphological characteristics related to the degree of domestication; to analyze the transferability of microsatellite primers (SSR - Simple Sequence Repeats) from C. annuum to C. frutescens and C. chinense; to confirm the existence of natural hybrids; to characterize the C. frutescens active germplasm collection of Embrapa Vegetables; to establish a core collection of C. frutescens and to compare the core collection to the base population of a breeding program. The research activities were carried out at Embrapa Vegetables, Embrapa Genetic Resources and Biotechnology and Embrapa Cerrados, in Brasilia, Federal District. Four wild accessions collected in the Amazon region (CNPH 4315, CNPH 4325B, CNPH 4337 and CNPH 4372) popularly known as olho-de-peixe or olho-de-periquito, were characterized using ISSR as C. chinense and presented fruits with traits typical of wild species. The wild accession CNPH 4353 known as malaguetinha was morphologically and molecularly classified as C. frutescens. Probably, these accessions collected in the Amazon Basin, the area with the largest diversity of C. chinense, share morphological characteristics with wild ancestors of this species. Transferability of a set of microsatellite primers of C. annuum was tested for the species C. frutescens and C. chinense. From the 185 C. annuum SSR primers (CA) analyzed, 116 (62.7%) showed transferability for both species. Of them, 19 (16.37%) were polymorphic with an average of 2.89 alleles per locus for C. frutescens and 35 (30.17%) showed polymorphism with an average of 3.3 alleles per locus for C. chinense. Based on the study of transferability, 17 CA primers can be used to analyze samples of C. chinense and C. frutescens. These two species are genetically very similar, making it difficult to distinguish the accessions, especially considering the possibile occurence of natural hybrids. To confirm the occurrence of natural interspecific hybrids, pollen viability and genetic compatibility tests were carried out, as well as morphological and molecular characterization with the analysis of capsaicinoids content. Although the species C. chinense and C. frutescens share similarities with overlapping morphological characteristics, they are actually different by analysis with SSR primers. Pollen viability and genetic compatibility tests pointed CNPH 4325A and CNPH 4361 as a result of natural hybridization, especially CNPH 4361, which showed morphological characteristics typical of both species, intermediate position in the dendrogram and in the scatter plot of the molecular analysis, occurrence of heterozygous alleles at six loci and intermediate content of capsaicin, of 154,000 SHU. The genetic variability of 115 accessions that compose the C. frutescens active germplasm collection of Embrapa Vegetables was based on 57 morphological characteristics and 239 alleles from 24 SSR loci. This study allowed the formation of six similarity groups in each analysis and showed that the accessions are diverse, presenting genetic variability for the development of cultivars of C. frutescens for a number of markets, such as the fresh-fruit and the processed-fruit (canning and sauces) markets. The SSR markers showed greater capacity for discrimination of morphological descriptors. Height and width of plants were the variables that showed the highest contribution to the coefficient of genetic diversity. A core collection was settled with 13 accessions of C. frutescens representing 77 % of the genetic variability of the active collection, gathering 239 alleles of 24 SSR loci, 57 morphological and agronomic characteristics and different selection strategies. The best strategy for settling the core collection was evidenced by the selection of accessions from different groups of similarity of the SSR analysis associated to the evaluation of incidence of viruses. Morphologic, agronomic and molecular characteristics were used to evaluate and compare the genetic variability of this core collection (13 accessions), a base population of the breeding program (6 accessions) an active collection (104 accessions) of C. frutescens. A higher genetic variability among accessions of the core collection was verified in comparison to the base population, both in the morphological and molecular characterization. The results show that accessions of the core collection can improve the genetic base of breeding programs of C. frutescens, maximizing the chances of desirable gene combinations. Made available in DSpace on 2018-10-12T00:46:46Z (GMT). No. of bitstreams: 1 2014SabrinaIsabelCostadeCarvalhoapagar.pdf: 3345455 bytes, checksum: 3215d3ce87c71dae6711fbd788c10b41 (MD5) Previous issue date: 2018-10-11 Tese (Doutorado) ? Universidade de Brasília/Faculdade de Agronomia e Medicina Veterinária, 2014. Orientador: Fábio Gelape Faleiro (CPAC). Co-orientadora: Gláucia Salles Cortopassi Buso.

Nesse estudo buscou-se selecionar descritores minimos para caracterização deacessos do banco de germoplasma de Capsicum spp. da Embrapa Hortaliças, caracterizado principalmente com base em dados de natureza qualitativa.

Doze linhagens de pimenta, incluindo exemplares do tipo Jalapeño (CNPH 2862, CNPH 2864), Dedo-de-Moça (CNPH 1397, CNPH 0039, CNPH 0053), Cmbuci (CNPH 0283), Peixe-Boi (CNPH 0434), Falsa Cumari (CNPH 3761), Bodo Vermelho (CNPH 3773), Biquinho Doce (CNPH 3870), Tabasco (CNPH 3000) E Malagueta (CNPH 2869) tiveram o comportamento meiotico e a estimativa da viabilidade do pólen analisados, com o objetivo de indicar materiais potencialmente férteis para o programa de melhoramento de Capsicum da Embrapa. Made available in DSpace on 2012-02-11T00:02:04Z (GMT). No. of bitstreams: 1 SabrinaHBv29n2p212216.pdf: 3018479 bytes, checksum: 1ce8019e13ec4023812bb06aefdbab4c (MD5) Previous issue date: 2011-08-01

Made available in DSpace on 2018-11-21T00:16:24Z (GMT). No. of bitstreams: 1 281.pdf: 1072105 bytes, checksum: 23d88c55cbe4a22818eaf4b11650ef20 (MD5) Previous issue date: 2010-04-12

Made available in DSpace on 2018-11-21T00:15:08Z (GMT). No. of bitstreams: 1 v27n2a02.pdf: 437150 bytes, checksum: 0aabf4a9d7c742947954bbf23863e99f (MD5) Previous issue date: 2009-09-17