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Registros recuperados: 40 | |
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Castro,Juliana P.; Moraes,Ana Paula; Chase,Mark W.; Santos,Angeline M. S.; Batista,Fabiane R. C.; Felix,Leonardo P.. |
ABSTRACT Cactaceae species are karyotypically well-known with x = 11 and chromosome number variation due mainly to polyploidization. However, both assumptions are based on descriptive observations without taking an evolutionary framework of Cactaceae into account. Aiming to confirm these hypotheses in an evolutionary context, we obtained chromosome numbers for 20 species of Cactoideae, performed an extensive review of chromosome number for the family, and analyzed these data using a phylogenetic approach. The karyotypes presented here were characterized by CMA/DAPI banding, and for six species 5S and 45S rDNA sites were located. Our data, along with a survey of the literature, reinforce the long-standing hypothesis of a x = 11 as the base chromosome number... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Base chromosome number; CMA/DAPI; Dysploidy; Heterochromatin; Polyploidy; RDNA. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062020000100135 |
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Alves,Mariana Ferreira; Duarte,Mariana Oliveira; Oliveira,Paulo Eugênio; Sampaio,Diana Salles. |
Polyploidization is common among angiosperms and might induce typically allogamous plants to become autogamous (self-compatible, relying on sexual self-fertilization) or apomictic (achieving asexual reproduction through seeds). This work aimed to determine whether neopolyploidy leads to the breakdown of the self-incompatibility system in the hexaploid non-apomictic species Handroanthus serratifolius (Vahl) S. Grose, through analyses of its floral biology, pollination biology and breeding system. Although anthesis lasted for three days, increasing the overall floral display, receptivity decreased as of the second day. Centridini and Euglossini bees were the main pollinators, and low nectar availability (1.95 ± 1.91 µl/flower) might have obliged them to... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Apomixis; Late-acting self-incompatibility; Monoembryony; Polyploidy; Tabebuia serratifolia. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000400010 |
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Cordeiro,Joel Maciel Pereira; Felix,Leonardo P.. |
ABSTRACT Although the chromosome number 2n = 28 predominates in most species of the genus Senna, variations are often observed, resulting from either polyploidy (2n = 42, 56, 112) or disploidy (2n = 22, 24, 26) events. To better understand the karyotypic variations in Senna, we examined heterochromatin patterns of 10 species of that genus using chromomycin A3 (CMA) and 4’6-diamidino-2-phenylindole (DAPI) staining, and reviewed information on the chromosome counts of 72 species of that genus. The CMA/DAPI banding patterns were relatively variable among the 10 species, both in terms of the numbers of bands (from two to 26) and their locations on the chromosomes (terminal or proximal regions). Our review indicated that 2n = 28 is the most common ploidy among... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome number; CMA/DAPI; Disploidy; Leguminosae; Polyploidy. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062018000100128 |
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Zappelini,Julia; Souza,Luiz Gustavo; Guerra,Miguel Pedro; Pescador,Rosete. |
ABSTRACT Although karyotype features are useful data for evolutionary studies, cytogenetic data in Bambusoideae are mainly based only on chromosome counts. The first comparative cytogenetic analysis of three Neotropical woody bamboo species - Guadua chacoensis, G. angustifolia and Chusquea tenella - was undertaken based on new and reviewed chromosome counts, CMA/DAPI double staining, fluorescent in situ hybridization (FISH) with 35S and 5S rDNA probes, and genome size estimation. The two species of Guadua were found to have 2n = 46 chromosomes, while the first record for C. tenella was 2n = 44. Only one pair of CMA+/DAPI- was detected on the terminal region of metacentric chromosomes in all three species. Likewise, one pair of 5S and 35S rDNA sites was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chusquea; Cytogenetics; Diploidization; Evolution; Guadua; Polyploidy. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062020000400673 |
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Skorupa,Ladislau A.. |
Chromosome counts for eight species of Pilocarpus Vahl (Rutaceae) a native of Brazil are reported for the first time. Chromosome numbers were determined from mitotic root tip cells of seedlings derived from field collections and grown in the greenhouse. Feulgen staining was used. Initial pre-treatment of root tips was done by using a saturated aqueous solution of alpha-bromonapthalene for two hours at room temperature (20-25ºC). Chromosome numbers of 2n=44 and 2n=88 were determined for the examined taxa. The present results suggest the occurrence of tetraploidy in P. spicatus St.-Hil. and P. carajaensis Skorupa, and a possible basic number x=22 to the genus Pilocarpus. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pilocarpus; Rutaceae; Cusparieae; Cytology; Polyploidy. |
Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062000000100002 |
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Unemoto, Lilian Keiko; UEL; Faria, Ricardo Tadeu de; UEL; Destro, Deonisio; UEL; Barbosa, Cristiane Muniz; UEL; Lone, Alessandro Borini; UEL. |
O objetivo deste trabalho foi verificar o efeito do ácido peracético e da colchicina na diferenciação de protocormos de Oncidium flexuosum. O ácido peracético foi testado previamente nas concentrações de 0, 3, 6 e 9 mL L-1, durante dez dias, para verificar a eficácia na esterilização do meio de cultura e os possíveis efeitos fitotóxicos nos protocormos. Após determinação da concentração, foram adicionados 6 mL L-1 de ácido peracético em meio MS com 0,05% de colchicina e DMSO 1%. Os protocormos foram mantidos em agitação pelos períodos: 0, 24, 48, 72, 96 e 120h. O experimento foi inteiramente casualizado com seis tratamentos, dez repetições e cinco protocormos por repetição. Após 30 dias, foi avaliada a sobrevivência dos protocormos e, após 180 dias, foram... |
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Palavras-chave: 5.01.00.00-9 Agronomia Orchidaceae; Poliploidia; Fitotoxicidade; Esterilização Fitotecnia Orchidaceae; Polyploidy; Phytotoxicity; Sterilization. |
Ano: 2009 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/697 |
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Sousa,Saulo M.; Torres,Giovana A.; Viccini,Lyderson F.. |
The genus Lippia (Verbenaceae) comprise around 160 species spread out mainly in South and Central Americas with few African species, some of them with potential medicinal use. Brazil is one the most important centers of diversity with approximately 75% of the species described so far. Innumerous species are endemic and poorly studied especially at a cytological level. Here, chromosomal length, karyomorphology and chromosome asymmetry of twelve Brazilian species of Lippia were evaluated [L. alba (Miller) N.E.Brown, L. diamantinensis Glaz., L. florida Cham., L. hermanioides Cham., L. lacunosa Mart. & Schauer, L. lupulina Cham., L. pohliana Schauer, L. pseudothea (St. Hil) Schauer, L. rosella Moldenke, L. rotundifolia Cham., L. rubella Moldenke and L.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomes; Cytology; Dysploidy; Karyology; Lippia; Polyploidy. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000400017 |
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Oliveira,Vanessa M. de; Forni-Martins,Eliana R.; Magalhães,Pedro M.; Alves,Marcos N.. |
In this study, we examined the chromosome number and some morphological features of strains of Stevia rebaudiana. The chromosomes were analyzed during mitosis and diakinesis, and the tetrad normality and pollen viability were also assessed. In addition, stomata and pollen were measured and some plant features were studied morphometrically. All of the strains had 2n = 22, except for two, which had 2n = 33 and 2n = 44. Pairing at diakinesis was n = 11II for all of the diploid strains, whereas the triploid and tetraploid strains had n = 11III and n = 11IV, respectively. Triploid and tetraploid plants had a lower tetrad normality rate than the diploids. All of the strains had inviable pollen. Thus, the higher the ploidy number, the greater the size of the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Asteraceae; Pollen; Polyploidy; Stevia rebaudiana; Stevioside; Stomata. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200015 |
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Burchardt,Paula; Souza-Chies,Tatiana T.; Chauveau,Olivier; Callegari-Jacques,Sidia M.; Brisolara-Corrêa,Lauís; Inácio,Camila Dellanhese; Eggers,Lilian; Siljak-Yakovlev,Sonja; de Campos,José Marcello Salabert; Kaltchuk-Santos,Eliane. |
Abstract Sisyrinchium is the largest genus of Iridaceae in the Americas and has the greatest amount of cytological data available. This study aimed at investigating how genomes evolved in this genus. Chromosome number, genome size and altitude from species of sect. Viperella were analyzed in a phylogenetic context. Meiotic and pollen analyses were performed to assess reproductive success of natural populations, especially from those polyploid taxa. Character optimizations revealed that the common ancestor of sect. Viperella was probably diploid (2n = 2x =18) with two subsequent polyplodization events. Total DNA content (2C) varied considerably across the phylogeny with larger genomes detected mainly in polyploid species. Altitude also varied across the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ancestral chromosome number; DNA content; Meiotic behavior; Pollen viability; Polyploidy. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000200288 |
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Cianciarullo,Aurora M.; Bonini-Domingos,Claudia R.; Vizotto,Luiz D.; Kobashi,Leonardo S.; Beçak,Maria-Luiza; Beçak,Willy. |
Abstract Two allopatric populations of Brazilian diploid and tetraploid Odontophrynus americanus species complex, both from São Paulo state, had their blood hemoglobin biochemically analyzed. In addition, these specimens were cytogenetically characterized. Biochemical characterization of hemoglobin expression showed a distinct banding pattern between the allopatric specimens. Besides this, two distinct phenotypes, not linked to ploidy, sex, or age, were observed in adult animals of both populations. Phenotype A exhibits dark-colored body with small papillae, ogival-shaped jaw with reduced interpupillary distance and shorter hind limbs. Phenotype B shows yellowish-colored body with larger papillae, arch-shaped jaw with broader interpupillary distance and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anura; Cryptic species; Hemoglobin differentiation; Polyploidy; Whole-genome duplication. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000300436 |
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Fregonezi,Jéferson N.; Torezan,José M.D.; Vanzela,André L.L.. |
The Asteraceae, one of the largest families of flowering plants, contains about 1,100 genera and 20,000 species, and is well known for its extensive karyotypic variation. In this study, conventional Feulgen staining, C-CMA3 banding, and fluorescence in situ hybridization with a 45S rDNA probe were used to determine the chromosome number and the number and physical position of GC-rich heterochromatin and 45S rDNA sites in three Asteraceae weed species (Crepis japonica, Galinsoga parviflora and Chaptalia nutans). The three species exhibited karyotype differences in the chromosome number and shape, as a commom feature of Asteraceae. However, the 45S rDNA sites always occurred on the short chromosomal arms, associated with GC-heterochromatin. Althought of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: CMA3; FISH; Heterochromatin; Polyploidy; 45S rDNA. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200016 |
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Alves,Lânia Isis F.; Lima,Saulo Antônio A.; Felix,Leonardo P.. |
The chromosomes of 15 species of Iridaceae of the genera Alophia, Cipura, Eleutherine, Neomarica and Trimezia (subfamily Iridoideae) were examined after conventional Giemsa staining. The karyotypes of Alophia drummondii (2n = 14+1B, 28, 42 and 56), Cipura paludosa (2n = 14), C. xanthomelas (2n = 28) and Eleutherine bulbosa (2n = 12) were asymmetric; Neomarica candida, N. caerulea, N. humilis, N. glauca, N. gracilis, N. northiana and Neomarica sp. (2n = 18); N. cf. paradoxa (2n = 28), Trimezia fosteriana (2n = 52), T. martinicensis (2n = 54) and T. connata (2n = 82) were all generally symmetric. New diploid numbers of 2n = 56 for Alophia drummondii, 2n = 18 for N. candida, N. humilis, N. glauca, and N. gracilis, 2n = 28 for N. cf. paradoxa, and 2n = 82 for... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Iridaceae; Disploidy; Karyotypic evolution; Polyploidy; Asymmetrical karyotype. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200016 |
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Pearson,Peter L.; Madan,Kamlesh. |
Abstract Polyploidy does not usually occur in germinal cells of mammals and other higher vertebrates. We describe a unique example of mosaic autotetraploidy in the meiosis of a human male. Although the original observations were made in the late 1960s, we did not publish them at that time, because we expected to detect further examples that could be described together. However, this did not occur and we have now decided to make the observations available to demonstrate that polyploidy in mammalian male meiosis can arise at a higher frequency than expected by random polyploidization of individual meiotic cells, by either DNA duplication or cell fusion prior to synapsis. This is the first description of a population of primary spermatocytes exhibiting... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Polyploidy; Meiosis; Human; Male. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000300410 |
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Xing,Shaochen; Cai,Yuhong; Zhou,Kaida. |
A triploid (2n = 3x = 36) rice plant was obtained by screening a twin seedling population in which each seed germinated to two or three sprouts that were then crossed with diploid plants. One diploid plant was chosen among the various F1 progenies and developed into an F2 population via self-pollination. Compared with the control variety Shanyou 63, this F2 population had a stable agronomical performance in field trials, as confirmed by the F-test. The stability of the F2 population was further substantiated by molecular analysis with simple sequence repeat markers. Specifically, of 160 markers assayed, 37 (covering all 12 chromosomes) were polymorphic between the parental lines. Testing the F1 hybrid individually with these markers showed that each PCR... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: F-test; Polyploidy; Rice; SSR marker; Stability. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200020 |
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Daviña,Julio Rubén; Grabiele,Mauro; Cerutti,Juan Carlos; Hojsgaard,Diego Hernán; Almada,Rubén Dario; Insaurralde,Irma Stella; Honfi,Ana Isabel. |
The center of diversity of Argentinean orchids is in the northeast region of the country. Chromosome numbers and karyotype features of 43 species belonging to 28 genera are presented here. Five chromosome records are the first ones at the genus level; these taxa are Aspidogyne kuckzinskii (2n = 42), Eurystyles actinosophila (2n = 56), Skeptrostachys paraguayensis (2n = 46), Stigmatosema polyaden (2n = 40) and Zygostates alleniana (2n = 54). In addition, a chromosome number is presented for the first time for 15 species: Corymborkis flava (2n = 56), Cyclopogon callophyllus (2n = 28), C. oliganthus (2n = 64), Cyrtopodium hatschbachii (2n = 46), C. palmifrons (2n = 46), Galeandra beyrichii (2n = 54), Habenaria bractescens (2n = 44), Oncidium edwallii (2n =... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome number; Karyotype features; Polyploidy; Karyology; Orchids; South America. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000400024 |
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Registros recuperados: 40 | |
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