Identification of molecular markers for foreground and background selection in Gа1-s incorporation into maize lines

Abstract

Marker assisted selection (MAS) significantly increases efficiency of conventional breeding. Molecular markers are utilized as selection markers for target genes (foreground selection) and also for identification of the genotypes (progenies) with the highest proportion of recurrent parent’s genome (background selection). Maize Research Institute "Zemun Polje" has a breeding program with the aim to create lines with incorporated incompatibility dominant gene Gametophytic Factor 1-S (Gа1-S), using the integrated conventional and molecular breeding approach. Ga1-S is the most described gene belonging to the group of genes specific to the pollen development, germination and pollen tube growth. The Ga1-S system is the most commonly used to prevent the pollination of sweetcorn, popcorn and white kerneld hybrids by standard maize. The objectives of this study were identification of gene-specific molecular marker for foreground selection, as well as the set of SSR markers polymorphic between parental lines to be used in background selection. Genetic variability between two donor and three recurrent parental inbred lines was analyzed with 42 SSRs distributed over the maize genom. Total number of alleles detected with 30 informative markers was 83, average being 2.77. The genetic similarity values calculated on Dice coefficient ranged from 0.47 to 0.71. Among 12 gene-specific markers tested on parental lines, two showed distinct polymorphism for Ga1-S. These markers will be used as foreground selection markers for the incorporation of Gа1-S into our inbred lines which will be used for the creation of white kernel hybrids.