|ZHANG, QIJUN - North Dakota State University|
|ZHONG, SHAOBIN - North Dakota State University|
|CAI, XIWEN - North Dakota State University|
|ELIAS, ELIAS - North Dakota State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/8/2017
Publication Date: 12/3/2017
Citation: Zhang, Q., Faris, J.D., Chao, S., Friesen, T.L., Zhong, S., Cai, X., Elias, E.M., Xu, S.S. 2017. Identification and molecular mapping of quantitative trait loci for resistance to Fusarium head blight in cultivated emmer PI 272527 [abstract]. In: Proceedings of the 2017 National Fusarium Head Blight Forum. December 3-5, 2017, Milwaukee, Wisconsin. p. 97.
Technical Abstract: Improvement of modern durum wheat (Triticum turgidum subsp. durum) for resistance to Fusarium head blight (FHB) has been seriously hampered worldwide due to lack of sources of high levels of resistance to this disease in durum germplasm. In searching for sources of FHB resistance that can be used for durum improvement, we identified a cultivated emmer wheat (T. turgidum subsp. dicoccum) accession, PI 272527, with a high level of resistance to FHB. To identify quantitative trait loci (QTL) associated with FHB resistance, a mapping population consisting of 219 recombinant inbred lines was developed from a cross between the durum variety ‘Divide’ and PI 272527. This population was genotyped using Illumina iSelect 90K array and a high density SNP linkage map was constructed with 10,486 SNP markers covering all 14 chromosomes. The population was also phenotyped for FHB resistance in two greenhouse and five field experiments during 2015 and 2016 growing seasons. Through homogeneity tests, we were able to combine disease severity data from the first greenhouse experiment and two field experiments in 2015 into one data set and combine the second greenhouse experiment and two of three field experiments in 2016 into another data set. However, the disease severity data collected from the third field experiment in 2016 could not be combined with either of the two combined data sets. Therefore, the SNP marker data and three sets of FHB data were used for subsequent QTL analysis. The results indicated that two QTL from Divide were detected on chromosomes 2A and 4A, and four QTL from PI 272527 were identified on chromosomes 1A, 3A, 5A, and 7B, respectively. The QTL on chromosome 5A, which conferred a major effect and was the only QTL detected in all greenhouse and field experiments, is likely the same as the one we previously identified in the hexaploid wheat line PI 277012. Based on the chromosomal location and the parentage information of Divide, the 2A QTL is likely the same as the one previously identified in durum variety ‘Ben’, suggesting that this QTL may be commonly present in the durum varieties developed by the North Dakota State University durum breeding program. Some of the QTL with minor effects derived from PI 272527 likely represent novel loci. Since PI 272527 is the most resistant genotype we have identified so far in tetraploid wheat germplasm collections, its high level of FHB resistance may be due to the additive effects of the QTL detected in this study.