Project name: Hordeum vulgare subsp. vulgare

Description: Germplasm collections hold valuable allelic diversity for crop improvement and genetic mapping of complex traits. To gain access to the genetic diversity within the USDA National Small Grain Collection (NSGC), we developed the Barley Recombinant Inbred Diverse Germplasm Population (BRIDG6) a 6-row spring barley multiparent population (MPP) with 88 landrace accessions crossed to a common parent (Rasmusson). The parents were randomly selected from a core subset of the NSGC that represents the genetic diversity of landrace and breeding accessions. In total, we generated 6,160 F5 recombinant inbred lines (RILs) with an average of 69 and a range of 37-168 RILs per family genotyped for 7,773 SNPs. The number of segregating SNPs per family range from 956 to 6,775, with an average of 3,889 SNPs per family. Using BRIDG6, we detected 13 QTL contributing to flowering time. Eight QTL were within five mega base pairs of previously described flowering time genes. For the major QTL detected near Ppd-H1, a photoperiodic flowering time gene, we observed both positive and negative allele effects ranging from +4 to –3 days relative to Rasmusson among the 79 families segregating for the SNP. To assess the impact of the number of families and lines used to construct a MPP, we bootstrap sampled different numbers of families and lines and compared QTL analyses to the entire population. Samples of 10 families were 100% effective in detecting major QTL, but less than 50% effective for minor QTL. Similarly, samples of 500 lines were 100% effective in detecting major QTL, but nearly the entire population was necessary to detect minor QTL. This MPP will be useful for detecting large and small effect QTL for traits of interest and identifying and utilizing valuable alleles from the NSGC for barley improvement.

Data type: raw sequence reads

Sample scope: Multiisolate

Relevance: Agricultural

Last updated: 2017-05-22