Data/hora: 23/09/2024 22:09:50

Biblioteca(s): 	Embrapa Acre.	
Tipo da produção científica: 	Artigo em Periódico Indexado	
Circulação/Nível: 	Nacional - A	
Data corrente: 	15/08/1996	
Data da última atualização: 	28/06/2021	
Autoria: 	OLIVEIRA, M. N. de; DAVIDE, L. C.; PINTO, C. A. B. P.	
Afiliação: 	MARCELO NASCIMENTO DE OLIVEIRA, CPAC; Lisete Chama Davide, Ufla; César Augusto Brasil Pereira Pinto, Ufla.	
Título: 	Mechanisms of 2n potato pollen formation in dihaploid Solanum tuberosum L. x S. chacoense Bitt. hybrid clones.	
Ano de publicação: 	1995	
Fonte/Imprenta: 	Brazilian Journal of Genetics, v. 18, n. 3, p. 445-450, 1995.	
ISSN: 	0100-8455	
Idioma: 	Inglês	
Conteúdo: 	The backcrosses of dihaploid Solanum tuberosum with wild species hybrids generating tetraploids progenies require the formation of non-reduced pollen. In this work, the mechanisms responsible for the formation of 2n pollen in 28 dihaploid Solanum tuberosum x Solanum chacoense hybrids were studied. Four mechanisms were found: parallelspindles (ps), fused spindles (fs), premature cytokinesis-1 (pc-1) and premature cytokinesis-2 (pc-2). The ps mechanism was the most frequent, being found in 23 of the 28 assessed clones. The ps and fs mechanisms led to the formation of dyads by first division restitution (FDR), transferring about 80% of the heterozygosity to the progenies. The pc-1 and pc-2 mechanisms also led to the formation of dyads, but they were genetically equivalent to second division restitution (SDR), transferring only 40% of the heterozygosity to the progenies. Occurrence of FDR and SDR were shown to be associated in 12 clones, indicating that the clones can produce non-reduced microspores by more than one mechanism. However, only one mechanism is functional in a single pollen-grain mother-cell. Clones 9-2, 9-3, 9-6 and 15-15 are recommended for use in 4x x 2x matings.	
Palavras-Chave: 	Clone híbrido; Fitomejoramiento; Híbridos; Patatas; Plant breendig; Retrocruzamiento; Solanum tuberosum L.	
Thesagro: 	Batata; Melhoramento genético vegetal; Progenie híbrida; Retrocruzamento.	
Thesaurus Nal: 	Backcrossing; Hybrids; Potatoes; Solanum chacoense.	
Categoria do assunto: 	G Melhoramento Genético	
URL: 	http://ainfo.cnptia.embrapa.br/digital/bitstream/item/154934/1/890.pdf	
Registro original: 	Embrapa Acre (CPAF-AC)	
Exemplares: 	CPAF-AC - (890-1) - UPC - AP - PP - SP 082 -  - 1996.00066 - DES
CPAF-AC - (890-2) - UPC - AP - DD -  -  -  - DIS