Your browser doesn't support javascript.
loading
Are cytological parameters of maize landraces (Zea mays ssp. mays) adapted along an altitudinal cline?
Fourastié, María Florencia; Gottlieb, Alexandra Marina; Poggio, Lidia; González, Graciela Esther.
Afiliação
  • Fourastié MF; Laboratorio de Citogenética y Evolución (LaCyE), Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
  • Gottlieb AM; Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina.
  • Poggio L; Laboratorio de Citogenética y Evolución (LaCyE), Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
  • González GE; Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina.
J Plant Res ; 131(2): 285-296, 2018 Mar.
Article em En | MEDLINE | ID: mdl-29177755
The Northwestern Argentina (NWA) highland region is one of the southernmost areas of native maize cultivation. We studied variations of different cytological parameters, such as DNA contents, presence/absence of B chromosomes (Bs), and number and sequence composition of heterochromatic knobs in ten accessions of four maize landraces growing along a broad altitudinal cline in NWA. The aim of this work was to assess variations in cytological parameters and their relationship with the crop altitude of cultivation, in an adaptive context. The A-DNA content of the A chromosome complements showed 40% of difference between the lowest (4.5 pg) and the highest (6.3 pg) 2C value. This variation could be attributed to differences in number and size of heterochromatic knobs. Fluorescent in situ hybridization studies revealed the sequence composition of each knob, with a higher proportion of knobs composed of 180-bp repeats rather than TR-1 repeats, in all accessions. We also found numerical polymorphisms and the highest frequency of Bs reported in maize to this date. These results lead us to propose that the frequencies and doses of Bs are influenced by the landrace genotypical make-up. The Bs might be maintained in higher frequencies in those accessions having lower heterochromatin content, so as to preserve an optimal nucleotype. Furthermore, selective forces acting along the altitudinal gradient might be modulating the cytological parameters studied, as suggested by the significant correlations found among them.
Assuntos
Palavras-chave
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Variação Genética / DNA de Plantas / Zea mays / Cromossomos de Plantas / Altitude País/Região como assunto: America do sul / Argentina Idioma: En Revista: J Plant Res Assunto da revista: BOTANICA Ano de publicação: 2018 Tipo de documento: Article País de afiliação: Argentina País de publicação: Japão
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Variação Genética / DNA de Plantas / Zea mays / Cromossomos de Plantas / Altitude País/Região como assunto: America do sul / Argentina Idioma: En Revista: J Plant Res Assunto da revista: BOTANICA Ano de publicação: 2018 Tipo de documento: Article País de afiliação: Argentina País de publicação: Japão