Molecular and General Genetics MGG

, Volume 247, Issue 5, pp 603–613

Identification of two opaque2 modifier loci in Quality Protein Maize

  • Mauricio A. Lopes
  • Koichi Takasaki
  • Dwight E. Bostwick
  • Tim Helentjaris
  • Brian A. Larkins
Original Paper


Genetic modifiers of opaque2 convert the soft, starchy endosperm of opaque2 maize mutants to a hard, vitreous phenotype, while maintaining the enhanced lysine content of the grain. Genetic analysis of F2 segregating seeds from crosses of opaque2 by modified opaque2 genotypes indicated that the modifiers are complex traits that act codominantly. We developed two different segregating F2 populations and mapped the modifier loci by restriction fragment length polymorphism (RFLP) analysis. A relationship was found between formation of vitreous endosperm and the locus encoding the gamma-zein storage protein, which maps near the centromere of chromosome 7. Endosperm modification was consistently associated with the presence of two rather than one gamma-zein gene at this locus. A second modifier locus was mapped near the telomere of chromosome 7L.

Key words

Gamma-zein Endosperm Storage protein Gene mapping 


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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • Mauricio A. Lopes
    • 1
  • Koichi Takasaki
    • 1
  • Dwight E. Bostwick
    • 1
  • Tim Helentjaris
    • 1
  • Brian A. Larkins
    • 1
  1. 1.Department of Plant SciencesUniversity of ArizonaTucsonUSA
  2. 2.National Maize and Sorghum Research CentreCNPMS/EMBRAPASete Lagoas - MGBrazil

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