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Registro Completo |
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Biblioteca(s): |
Embrapa Gado de Corte. |
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Data corrente: |
30/09/2009 |
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Data da última atualização: |
13/10/2009 |
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Autoria: |
RISSO-PASCOTTO, C.; PAGLIARINI, M. S.; VALLE, C. B. do; JANK, L. |
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Afiliação: |
C. RISSO-PASCOTTO, UEM; MARIA SUELY PAGLIARINI, UEM; CACILDA BORGES DO VALLE, CNPGC; LIANA JANK, CNPGC. |
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Título: |
Symmetric pollen mitosis I and suppression of pollen mitosis II prevent pollen development in Brachiaria jubata (Gramineae). |
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Ano de publicação: |
2005 |
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Fonte/Imprenta: |
Brazilian Journal of Medical and Biological Research, Ribeirão Preto, v.38, n.11, p. 1603-1608, nov. 2005. |
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Idioma: |
Português |
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Conteúdo: |
Microsporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36) accession of the forage grass Brachiaria jubata
(BRA 007820) from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains
were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious
chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After
callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its
differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the
typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation
and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did
not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain.
The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The
absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and
could explain, at least in part, why seed production is low when compared with the amount of flowers per raceme. MenosMicrosporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36) accession of the forage grass Brachiaria jubata
(BRA 007820) from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains
were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious
chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After
callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its
differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the
typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation
and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did
not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain.
The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The
absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and
c... Mostrar Tudo |
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Palavras-Chave: |
Brachiaria jubata; Braquiária; Microsporogênese. |
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Thesagro: |
Gramínea Forrageira; Melhoramento Genético Vegetal; Pastagem. |
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Categoria do assunto: |
F Plantas e Produtos de Origem Vegetal |
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Marc: |
LEADER 02366naa a2200229 a 4500
001 1512794
005 2009-10-13
008 2005 bl --- 0-- u #d
100 1 $aRISSO-PASCOTTO, C.
245 $aSymmetric pollen mitosis I and suppression of pollen mitosis II prevent pollen development in Brachiaria jubata (Gramineae).
260 $c2005
520 $aMicrosporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36) accession of the forage grass Brachiaria jubata (BRA 007820) from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain. The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and could explain, at least in part, why seed production is low when compared with the amount of flowers per raceme.
650 $aGramínea Forrageira
650 $aMelhoramento Genético Vegetal
650 $aPastagem
653 $aBrachiaria jubata
653 $aBraquiária
653 $aMicrosporogênese
700 1 $aPAGLIARINI, M. S.
700 1 $aVALLE, C. B. do
700 1 $aJANK, L.
773 $tBrazilian Journal of Medical and Biological Research, Ribeirão Preto$gv.38, n.11, p. 1603-1608, nov. 2005.
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Registro original: |
Embrapa Gado de Corte (CNPGC) |
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| Registros recuperados : 30 | |
| 5. |  | SANTOS, A. T. dos; MATTOS, P. P. de; BRAZ, E. M.; MACHADO, S. do A.; FREITAS, J. V. de. Estrutura diamétrica de Bauhinia forficata, Commiphora leptophloeos, Croton sonderianus e Pityrocarpa moniliformis no bioma Caatinga. In: CONFERÊNCIA IUFRO 2023 AMÉRICA LATINA, 2023, Curitiba. Anais... Colombo: Embrapa Florestas, 2023. p. 118. (Embrapa Florestas. Eventos técnicos & científicos, 2).| Tipo: Resumo em Anais de Congresso |
| Biblioteca(s): Embrapa Florestas. |
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| 6. | | LUZ, N. B. da; GARRASTAZU, M. C.; ROSOT, M. A. D.; MARAN, J. C.; OLIVEIRA, Y. M. M. de; FRANCISCON, L.; CARDOSO, D. J.; FREITAS, J. V. de. Brazilian National Forest Inventory: a landscape scale approach to monitoring and assessing forested landscapes. Pesquisa Florestal Brasileira, Colombo, v. 38, e201701493, 2018. 14 p. Artigo de revisão.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: B - 3 |
| Biblioteca(s): Embrapa Florestas. |
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| 8. | | LUZ, N. B. da; OLIVEIRA, Y. M. M. de; ROSOT, M. A. D.; GARRASTAZU, M. C.; FRANCISCON, L.; MESQUITA JÚNIOR, H. N. de; FREITAS, J. V. de. Classificação híbrida de imagens Landsat-8 e RapidEye para o mapeamento do uso e cobertura da terra nas Unidades Amostrais de Paisagem do Inventário Florestal Nacional do Brasil. In: SIMPÓSIO BRASILEIRO DE SENSORIAMENTO REMOTO, 17., 2015, João Pessoa. Anais... São José dos Campos: INPE, 2015. p. 7222-7230. Disponível online.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Florestas. |
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| 9. | | LUZ, N. B. da; OLIVEIRA, Y. M. M. de; ROSOT, M. A. D.; GARRASTAZU, M. C.; MATTOS, P. P. de; FRANCISCON, L.; FREITAS, J. V. de. Classificação de imagens orientada a objetos como suporte ao componente geoespacial do Inventário Florestal Nacional Brasileiro. In: SIMPÓSIO NACIONAL DE INVENTÁRIO FLORESTAL, 3., 2014, Manaus. Anais... Brasília, DF: Serviço Florestal Brasileiro, 2014. p. 126. Disponível online. Resumo.| Tipo: Resumo em Anais de Congresso |
| Biblioteca(s): Embrapa Florestas. |
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| 12. | | FREITAS, J. V. de; OLIVEIRA, Y. M. M. de; ABRANTES, M. A.; MATTOS, P. P. de; SCHAITZA, E. G.; PICHELLI, K. R.; AFONSO, S. R. Memórias do XXV Congresso Mundial da IUFRO, Curitiba, Paraná, Brasil, 29 de setembro a 5 de outubro de 2019. Brasília, DF: Embrapa, 2020. 104 p. il. color. Contém apêndices e anexos.| Tipo: Autoria/Organização/Edição de Livros |
| Biblioteca(s): Embrapa Florestas. |
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| 13. | | FREITAS, J. V. de; OLIVEIRA, Y. M. M. de; ABRANTES, M. A.; MATTOS, P. P. de; SCHAITZA, E. G.; PICHELLI, K. R.; AFONSO, S. R. Memories of the 25th IUFRO World Congress, Curitiba, Paraná, Brazil, September 29 to October 5, 2019. Brasília, DF: Embrapa, 2020. 104 p. il. color. Contém apêndices e anexos.| Tipo: Autoria/Organização/Edição de Livros |
| Biblioteca(s): Embrapa Florestas. |
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| 14. | | PINTO, A. S. S.; BRONDI, M. G.; FREITAS, J. V. de; RIBEIRO, M. P. A.; GIORDANO, R. C.; FARINAS, C. S. Mitigação do impacto negativo de inibidores da produção de etanol celulósico em biorrefinarias por processo de lavagem concomitante com a adição de proteína de soja. In: SIMPÓSIO NACIONAL DE INSTRUMENTAÇÃO AGROPECUÁRIA, 4., 2019, São Carlos, SP. Ciência, inovação e mercado: anais. São Carlos, SP: Embrapa Instrumentação, 2019. Editores: Paulino Ribeiro Villas-Boas, Maria Alice Martins, Débora Marcondes Bastos Pereira Milori, Ladislau Martin Neto. SIAGRO 2019. 263-266| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Instrumentação. |
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| 17. | | LUZ, N. B. da; OLIVEIRA, Y. M. M. de; ROSOT, M. A. D.; GARRASTAZU, M. C.; MESQUITA JÚNIOR, H. N. de; FREITAS, J. V. de; COSTA, C. R. da. Developments in forest monitoring under the Brazilian National Forest Inventory: multi-source and hybrid image classification approaches. In: WORLD FORESTRY CONGRESS, 14., 2015, Durban. Forests and people: investing in a sustainable future. Rome: FAO, 2015. 8 p.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Florestas. |
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| 18. | | FREITAS, J. V. de; PINHO, G. S. C. de; LEÃO, R. A.; MESQUITA JUNIOR, H. N. de; BRENA, D. A.; MATTOS, P. P. de; OLIVEIRA, Y. M. M. de. National Forest Inventory of Brazil. In: RAMÍREZ, C.; ALBERDI, I.; BAHAMONDEZ, C.; FREITAS, J. V. de. National Forest Inventories of Latin America and the Caribbean: towards the harmonization of forest information. Rome: FAO, 2022. p. 102-119.| Tipo: Capítulo em Livro Técnico-Científico |
| Biblioteca(s): Embrapa Florestas. |
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| 19. | | LUZ, N. B. da; MARAN, J. C.; GARRASTAZU, M. C.; ROSOT, M. A. D.; FRANCISCON, L.; HOLLER, W. A.; GAIAD, N. P.; OLIVEIRA, Y. M. M. de; FREITAS, J. V. de. Manual de análise de paisagem: volume 1: procedimentos para a execução do mapeamento de uso e cobertura da terra. Colombo: Embrapa Florestas, 2018. 92 p. (Embrapa Florestas. Documentos, 316).| Biblioteca(s): Embrapa Florestas. |
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| 20. | | OLIVEIRA, Y. M. M. de; ROSOT, M. A. D.; GARRASTAZU, M. C.; PENTEADO JUNIOR, J. F.; MATTOS, P. P. de; LACERDA, A. E. B. de; PONZONI, F. J.; FREITAS, J. V. de; GOMIDE, L. A.; CIESLA, W. Evaluación de la acuracidade del mapeo de la vegetación del Inventario Forestal Nacional de Brasil. In: CONGRESO FORESTAL MUNDIAL, 13., 2009, Buenos Aires. Desarrollo forestal: equilibrio vital. Argentina: FAO, 2009. 12 p. CD-ROM.| Tipo: Artigo em Anais de Congresso / Nota Técnica |
| Biblioteca(s): Embrapa Florestas. |
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| Registros recuperados : 30 | |
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