Data/hora: 15/05/2024 19:09:14

Biblioteca(s): 	Embrapa Agricultura Digital.	
Data corrente: 	26/05/2009	
Data da última atualização: 	01/12/2010	
Autoria: 	PAGLIARINI, M. S.; RICCI, G. L.; SILVA, N. da; SCAPIM, C. A.	
Afiliação: 	MARIA SUELY PAGLIARINI, UEM; GLÉIA LAVERDE RICCI, UEM; NEIDE DA SILVA, UEM; CARLOS ALBERTO SCAPIM, UEM.	
Título: 	Interchanges in popcorn (Zea mays L.) involving the nucleolus organizer chromosome.	
Ano de publicação: 	2006	
Fonte/Imprenta: 	Crop Breeding and Applied Biotechnology, Londrina, v. 6, n. 3, p. 203-208, June 2006.	
Idioma: 	Inglês	
Conteúdo: 	The analysis of microsporogenesis in endogamous plants of popcorn (S5 to S7) showed several and distinct interchanges which involve the nucleolus organizer (chromosome 6). This detection of cells with interchanges was facilitated by the presence of two nucleoli of different sizes in contrast to normal ones with a single big nucleolus. Interchange points do not always seem to be at the same place. Whereas in several situations the interchange point clearly involved more than two chromosome pairs, a simple terminal translocation seemed to occur in others. During diplotene, a cross-shaped configuration connected with the nucleoli was observed in some meiocytes. Some heteromorphic bivalents were found during diakinesis, after which meiosis progressed normally to the end and gave rise to apparently normal tetrad with one normal nucleolus in each microspore. Tests of pollen viability in fixed pollen grains showed 100% stainability in normal and in affected plants. This is the first report on chromosome interchanges in popcorn.	
Palavras-Chave: 	Cromossomo 6; Organizador nucleolar.	
Thesagro: 	Agricultura; Biotecnologia; Genética; Meiose; Milho Pipoca; Translocação; Zea Mays.	
Categoria do assunto: 	G Melhoramento Genético	
Registro original: 	Embrapa Agricultura Digital (CNPTIA)	
Exemplares: 	CNPTIA - (12935-1) - ADD - AP - PP -  -  -  - DIS