Data/hora: 04/06/2024 04:34:28

Biblioteca(s): | Embrapa Gado de Corte.
Data corrente: | 02/04/2009
Data da última atualização: | 01/08/2011
Autoria: | FELISMINO, M. F.; PAGLIARINI, M. S.; VALLE, C. B. do.
Afiliação: | Mariana Ferrari Felismino, UEM; Maria Suely Pagliarini, UEM; Cacilda Borges do Valle, CNPGC.
Título: | A differential phenotypic expression of a divergent spindle mutation in interspecific Brachiaria hybrids.
Ano de publicação: | 2008
Fonte/Imprenta: | Cell Biology International, v. 32, p. 1459-1463, Nov. 2008. Issue 11.
Idioma: | Inglês
Conteúdo: | Several mutations are known to alter the normal progression of meiosis and can be correlated with defects in microtubule distribution. The dv mutation affects the spindle organization and chromosomes do not converge into focused poles. Two Brachiaria hybrids presented the phenotypic expressions of dv mutation but exhibited many more details in the second division. Bivalents were distantly positioned and spread over a large metaphase plate and failed to converge into focused poles. Depending on the distance of chromosomes at the poles, telophase I nuclei were elongated or the chromosomes were grouped into various micronuclei of different sizes in each cell. The first cytokinesis occurred. However, when there were micronuclei, a second cytokinesis immediately took place dividing the prophase II meiocytes into three or four cells. In each meiocyte, meiosis progressed to the second division. Slightly elongated nuclei or micronuclei were recorded in telophase II. After a third cytokinesis, hexads or octads were formed. Pollen grains of different sizes were generated. One of these hybrids presented a higher frequency of abnormal cells than when previously analyzed. The fate of these hybrids as genitors or as candidates for cultivars in the Brachiaria breeding program is discussed.
Palavras-Chave: | Braquiária; Brasil; Campo Grande; Mato Grosso do Sul.
Thesagro: | Brachiaria; Citogenética Vegetal; Gramínea Forrageira; Hibrido; Meiose; Melhoramento Genético Vegetal; Pastagem.
Categoria do assunto: | --
URL: | http://ainfo.cnptia.embrapa.br/digital/bitstream/item/39007/1/sdarticle.pdf
Registro original: | Embrapa Gado de Corte (CNPGC)
Exemplares: | CNPGC - (12369-1) - UPC - AP - DD - 461/18 -  - 461/18 - DIS