Location: Cereal Crops ResearchTitle: Fighting against FHB – an excellent novel resistance source for future wheat breeding) Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/6/2010
Publication Date: 12/7/2010
Citation: Chu, C., Zhong, S., Chao, S., Friesen, T.L., Halley, S., Elias, E.M., Faris, J.D., Xu, S.S. 2010. Fighting against FHB – an excellent novel resistance source for future wheat breeding. Meeting Abstract. pg. 14. Interpretive Summary:
Technical Abstract: Fusarium head blight (FHB) is a devastating wheat disease that causes tremendous economic losses by reducing grain yield and quality in wheat-growing areas worldwide. Sources of resistance are critical for genetically improving wheat for resistance to FHB. From a large-scale evaluation of tetraploid wheat (Triticum turgidum) germplasm for resistance reactions to FHB, we identified an accession (PI 277012) that consistently showed a high level of resistance across all environments in both greenhouse and field experiments. PI 277012 is currently classified as tetraploid emmer wheat (T. turgidum subsp. dicoccum) in the National Small Grains Collection, but somatic chromosome counts revealed that this accession was actually a hexaploid wheat. To characterize the FHB resistance in this accession, we developed a doubled haploid (DH) mapping population consisting of 130 lines from the cross between PI 277012 and the hard red spring wheat cultivar ‘Grandin’. The DH population was then evaluated for reaction to FHB under three greenhouse seasons and five field environments. Based on whole genome linkage maps that consisted of 350 SSR markers spanning 2,703 cM of genetic distance, two major FHB resistance QTLs were identified on chromosome arms 5AS and 5AL. The 5AS QTL peaked at the marker interval between Xbarc180 and Xwmc795, and explained up to 25% of the phenotypic variation. The 5AL QTL explained up to 35% of the trait variation and peaked at the interval between markers Xwmc470 and Xgwm595. FHB resistance has not previously been reported to be associated with this particular genomic region of chromosome arm 5AL, thus indicating the novelty of FHB resistance in PI 277012. Furthermore, the FHB resistance effects of neither QTL were associated with plant height and maturity. Elite agronomic traits were observed among several FHB-resistant DH lines. Therefore, these results suggest that PI 277012 is an excellent source for improving FHB resistance in wheat. The markers identified in this research are being used for marker-assisted introgression of the QTLs into adapted durum and hard red spring wheat cultivars.