Plant Biotechnology
  Molecular Biology and Genetics
Electronic Journal of Biotechnology ISSN: 0717-3458 Vol. 14 No. 1, Issue of January 15, 2011
© 2011 by Pontificia Universidad Católica de Valparaíso -- Chile Received May 19, 2010 / Accepted October 29, 2010
DOI: 10.2225/vol14-issue1-fulltext-7  
RESEARCH ARTICLE

Natural selection in common bean microsatellite alleles and identification of QTLs for grain yield

Monik Evelin Leite1 · João Bosco dos Santos*1 · Flávia Fernandes Carneiro1 · Karla Rodrigues Couto1 

1Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG, Brasil

*Corresponding author: jbsantos@ufla.br

Financial support: National Council of Technological and Scientific Development (CNPq) and Coordination for the Improvement of Higher Education Personnel (CAPES).

Keywords: bulk method, fitness coefficient, Phaseolus vulgaris, SSR markers.

Abstract   Full Text

Natural selection acts to select better adapted individuals or alleles in segregating population and help plant breeding. The objective of this work was to verify the effect of natural selection on microsatellite alleles as indicators of better adaptation and identification of quantitative trait loci (QTLs) for grain yield. This study evaluated 107 progenies from the F8 and 107 from the F24 generation derived from crossing Carioca MG and ESAL 686 lines, carried out by the bulk method, and evaluated in three different seasons: winter 2001; rainy 2001 and dry 2002. It utilized 22 polymorphic markers and the natural selection acted in all of them. The frequency of the alleles of the parent Carioca MG, the most adapted, was increased in all of the 22 loci in F8 and 19 loci in F24. Selection affected each locus with different intensities in different generations. All of the selected alleles can be important for breeding program. QTLs were identified in generation F8 and F24 at varied magnitudes. The best marker PVttc002 explained 11.76% of variation in grain yield. However, an elevated interaction between QTLs and the environments was observed, showing the great difficulty in assisted selection.

Supported by UNESCO / MIRCEN network