Mapping QTL for Fusarium head blight resistance in a Tunisian-derived durum wheat population

Authors: PIRSEYEDI, SEYED - North Dakota State University; KUMAR, AJAY - North Dakota State University; GHAVAMI, FARHAD - North Dakota State University; HEGSTAD, JUSTIN - North Dakota State University; MERGOUM, MOHAMED - North Dakota State University; MAZAHERI, MONA - North Dakota State University; Kianian, Shahryar; ELIAS, ELIAS - North Dakota State University

Submitted to: Cereal Research Communications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/4/2018
Publication Date: 11/19/2018
Citation: Pirseyedi, S.M., Kumar, A., Ghavami, F., Hegstad, J.B., Mergoum, M., Mazaheri, M., Kianian, S.F., Elias, E.M. 2018. Mapping QTL for Fusarium head blight resistance in a Tunisian-derived durum wheat population. Cereal Research Communications. 47(1):78-87.

Interpretive Summary: Fusarium head blight (FHB) is a major disease of wheat affecting yield and quality in many wheat growing regions of the U.S. This study deciphers the genetics of FHB resistance from a tetraploid germplasm from Tunisia for use in durum wheat breeding. Regions of genome controlling resistance to FHB, Fusarium-damaged kernels and mycotoxin levels in the seed were determined. Chromosomal segments that control these traits were identified on various genomic regions. Two novel regions impacting disease severity were identified with tagged molecular markers for use in breeding improved cultivars. A novel region on chromosome 2B was identified impacting the traits under study that could improve all disease related traits. This information is being used in regional breeding programs to develop more resistant durum wheat cultivars.

Technical Abstract: Fusarium head blight (FHB) damage in durum wheat (Triticum turgidum L. var. durum Desf., turgidum) inflicted massive economic losses worldwide. Meanwhile, FHB resistant durum wheat germplasm is extremely limited. 'Tunisian108' is a newly identified tetraploid wheat with FHB resistance. However, genomic regions in 'Tunisian108' that significantly associated with FHB resistance are yet unclear. Therefore, a population of 171 backcross inbred lines (BC1F7) derived from a cross between 'Tunisian108' and a susceptible durum cultivar 'Ben' was characterized. Fusarium graminearum (R010, R1267, and R1322) was point inoculated (greenhouse) or spawn inoculated (field) in 2010 and 2011. Disease sever-ity, Fusarium-damaged kernel (FDK) and mycotoxins were measured. Analysis of variance showed significant genotype and genotype by environment effect on all traits. Approximately 8% of the lines in field and 25% of the lines in greenhouse were more resistance than Tunisian108. A framework linkage map of 267 DArt plus 62 SSR markers was developed representing 239 unique loci and covering a total distance of 1887.6 cM. Composite interval mapping revealed nine QTL for FHB severity, four QTL for DON, and four QTL for FDK on seven chromosomes. Two novel QTL, Qfhb.ndsu-3BL and Qfhb.ndsu-2B, were identified for disease severity, explaining 11 and 6% of the phenotypic variation, respectively. Also, a QTL with large effect on severity and a QTL with negative effect on FDK on chromosome 5A were identified. Importantly, a novel region on chromosome 2B was identified with mul-tiple FHB resistance. Validation on these QTL would facilitate the durum wheat resistance breeding.