Building a Bridge from the Barley National Germplasm Collection to Breeding Programs

The barley nested association mapping population developed by the Triticeae Coordinated Agriculture Program can serve as a library of the genetic diversity in barley. It was created by crossing 91 diverse parents from the NSGC Core Collection to the cultivar Rasmusson and creating ~80 recombinant inbred lines per cross. In the summer of 2014, we collected phenotypic data for height, bacterial leaf streak, and heading date for the NAM population and the parents. This population is also being characterized through genotyping by sequencing to enable trait mapping. Because of its large size, phenotyping the NAM population will be challenging for some traits. Therefore, we will investigate approaches to strategically phenotype subsets. One approach we will use will be to assess genetic variation for traits within the NAM and to determine if phenotypic differences among parents are correlated to the corresponding progeny variance, thus suggesting which subpopulations within the NAM will be useful to phenotype. Another approach will be to develop a mini-NAM for preliminary phenotyping using marker data that is informative across the genome. A third approach will involve developing mapping panels that represent haplotype diversity for candidate gene regions. QTL discovered through these approaches can then be easily transferred through marker assisted selection to breeding programs to address a wide array of traits. Progress toward evaluating these approaches will be presented.