EVALUATION AND IMPROVEMENT OF CEREAL GERMPLASM FOR DISEASE RESISTANCE AND WINTER-HARDINESS
Location: Plant Science Research
Title: Marker development and quantitative trait loci for a fall-sown oat recombinant inbred population
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 23, 2010
Publication Date: January 3, 2011
Citation: Maloney, P.V., Lyerly, J.H., Wooten, D.R., Anderson, J.M., Livingston, D.P., Brown Guedira, G.L., Marshall, D.S., Murphy, J.P. 2011. Marker development and quantitative trait loci for a fall-sown oat recombinant inbred population. Crop Science. 51:490-502.
Interpretive Summary: Correlating specific pieces of DNA with freezing tolerance is one way to identify freezing tolerant plants without freeze testing them. These pieces of DNA related to freezing tolerance are called quantitative trait loci (QTL). In this study 2 winter oats were crossed and 128 of their projeny were freeze tested and analyzed for QTL that were related to freezing. In this study single sequence repeats (SSR) were used as DNA markers because they are much easier to process. Seventy new markers were added to the population which greatly expands breeders ability to select freezing tolerant germplasm in early generations without having to freeze test them and may help breeders select new freezing tolerant cultivars.
Avena sativa (L), or common cultivated oat, has the poorest winter hardiness among the small grain cereals. Marker-assisted selection for improved winter survival in oat is difficult, as the number of SSR markers available in this species is limited. The objectives of this research were to increase the number of SSR markers on the ‘Fulghum’ x ‘Norline’ recombinant inbred population genetic map, and to scan for QTL associated with winter hardiness component traits, including winter field survival, crown freezing tolerance, vernalization response, and heading date. SSR markers were developed from ‘Kanota’ and ‘Ogle’ genomic DNA libraries that were enriched for eight microsatellite motifs. New primers were evaluated for amplification, reproducibility, and polymorphism in 11 oat lines. SSRs showing high-quality polymorphism between Fulghum and Norline were subsequently examined in 128 recombinant inbred lines. 70 new markers were added to the Fulghum x Norline recombinant inbred population, which consisted of 4 SNPs, 1 Caps, and 65 SSR markers. Phenotypic data for winter hardiness component traits in the population were obtained in field and controlled chamber experiments. All previously mapped markers and new SSR markers were evaluated and QTL identified. Marker loci on linkage group FN3 accounted for multiple QTL associated with winter hardiness component traits. The markers found to be associated with winter hardiness will further assist breeders in selecting for winter hardy oats.