Identification and mapping of quantitative trait loci for Fusarium head blight resistance in a synthetic hexaploid × hard red spring wheat population

Authors: SZABO-HEVER, AGNES - Oak Ridge Institute For Science And Education (ORISE); SHARMA, JYOTI - North Dakota State University; Faris, Justin; ZHONG, SHAOBIN - North Dakota State University; Friesen, Timothy; Fiedler, Jason; GREEN, ANDREW - North Dakota State University; Bai, Guihua; ELIAS, ELIAS - North Dakota State University; Xu, Steven

Submitted to: The Plant Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2025
Publication Date: 7/9/2025
Citation: Szabo-Hever, A., Sharma, J., Faris, J.D., Zhong, S., Friesen, T.L., Fiedler, J.D., Green, A., Bai, G., Elias, E.M., Xu, S.S. 2025. Identification and mapping of quantitative trait loci for Fusarium head blight resistance in a synthetic hexaploid × hard red spring wheat population. The Plant Genome. 18(3). Article e70073. https://doi.org/10.1002/tpg2.70073.
DOI: https://doi.org/10.1002/tpg2.70073

Interpretive Summary: Fusarium head blight (FHB), commonly known as scab, is one of the most devastating diseases in wheat. A synthetic wheat line Largo, developed from cross between durum wheat and goatgrass species Aegilops tauschii, was previously found to have a high level of FHB resistance. To identify the FHB resistance genes in Largo, we genetically analyzed a population of 188 pure lines developed from a cross between the susceptible wheat line ND495 and Largo with molecular markers and evaluated the population for FHB resistance in two greenhouse seasons and two field environments. Based on genetic analysis, we identified six genes for FHB resistance, with two and four of the genes being derived from ND495 and Largo, respectively. The genes and their associated molecular markers identified in this study provide new resources for wheat breeders in improving FHB resistance in modern wheat varieties. Identification of these genes from the resistant and susceptible parents further suggests that an effective strategy to improve FHB resistance.is to stack multiple resistance genes together while also eliminating susceptibility genes.

Technical Abstract: Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe, is one of the most devastating diseases in wheat (Triticum aestivum L.). A synthetic hexaploid wheat line Largo, developed from cross between the durum wheat (T. turgidum ssp. durum (Desf.) Husn.] variety ‘Langdon’ and the Aegilops tauschii Cosson accession PI 268210, was previously found to have a high level of FHB resistance. This study was conducted to identify resistance quantitative trait loci (QTL) using a population of 188 recombinant inbred lines (RILs) from a cross between Largo and the susceptible wheat line ND495. The RILs were evaluated for Type II resistance in two greenhouse seasons and two field environments. The disease severity and existing 90K SNP marker data were used for QTL analysis, which led to the identification of six QTL on chromosomes 1D, 2D, 5B, and 7D. Four QTL (QFhb.rwg-1D, -5B, -7D.1, and -7D.3) with minor effects were derived from Largo, whereas two (QFhb.rwg-2D and -7D.2) with larger effects were from ND495. Five QTL collocated or overlapped with previously reported QTL, whereas QFhb.rwg-1D located in a region with no known QTL, suggesting that it is a novel QTL. QFhb.rwg-2D was the only QTL detected in all four environments and it is likely the same QTL as the major and stable 2D QTL present in many wheat varieties. The QTL detected from the resistant and susceptible parents enhance our understanding of FHB resistance expression and provide new resources for improving FHB resistance in wheat.