Location: Hard Winter Wheat Genetics ResearchTitle: Precisely mapping a major gene conferring resistance to Hessian fly in bread wheat using genotyping-by-sequencing
|LI, GENQIAO - Oklahoma State University|
|WANG, YING - Oklahoma State University|
|POLAND, JESSE - Kansas State University|
|AKHUNOV, EDWARD - Kansas State University|
|CARVER, BRETT - Oklahoma State University|
|YAN, LIULING - Oklahoma State University|
Submitted to: Biomed Central (BMC) Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/29/2015
Publication Date: 2/21/2015
Publication URL: http://www.biomedcentral.com/content/pdf/s12864-015-1297-7.pdf
Citation: Li, G., Wang, Y., Chen, M., Edae, E.A., Poland, J.A., Akhunov, E., Chao, S., Bai, G., Carver, B.F., Yan, L. 2015. Precisely mapping a major gene conferring resistance to Hessian fly in bread wheat using genotyping-by-sequencing. Biomed Central (BMC) Genomics. 16:108. doi:10.1186/s12864-015-1297-7.
Interpretive Summary: The Hessian fly Mayetiola destructor is one of the most destructive pests of wheat. The insect pest is mainly controlled by developing resistant cultivars. However, the resistance conferred by specific resistance genes is often short-lived, lasting for only 6-8 years. A better understanding of the mechanisms that lead to wheat resistance to Hessian fly is needed in order to improve durability of wheat resistance. In this study, we mapped one Hessian fly resistance gene in wheat to a small chromosome region by genotyping-by-sequencing. This work provides a basis for the eventual cloning of this resistance gene.
Technical Abstract: Background One of the reasons hard red winter wheat cultivar ‘Duster’ (PI 644016) is widely grown in the southern Great Plains is that it confers a consistently high level of resistance to biotype GP of Hessian fly (Hf). However, little is known about the genetic mechanism underlying Hf resistance in Duster. This study aimed to unravel complex structures of the Hf region on chromosome 1AS in wheat by using genotyping-by-sequencing (GBS) markers and single nucleotide polymorphism (SNP) markers. Results Doubled haploid (DH) lines generated from a cross between two winter wheat cultivars, ‘Duster’ and ‘Billings’', were used to identify genes in Duster responsible for effective and consistent resistance to Hf. Segregation in reaction of the 282 DH lines to Hf biotype GP fit a one-gene model. The DH population was genotyped using 2,358 markers developed using the GBS approach. A major QTL, explaining 88% of the total phenotypic variation, was mapped to a chromosome region that spanned 178 cM and contained 205 GBS markers plus 1 SSR marker and 1 gene marker, with 0.86 cM per marker in genetic distance. The analyses of GBS marker sequences and further mapping of SSR and gene markers enabled location of the QTL-containing linkage group on the short arm of chromosome 1A. Comparative mapping of the common markers for the gene for QHf.osu-1Ad in Duster and the Hf-resistance gene for QHf.osu-1A74 in cultivar ‘2174’ showed that the two Hf resistance genes are located on the same chromosome arm 1AS, only 11.2 cM apart in genetic distance. The gene at QHf.osu-1Ad in Duster has been delimited within a 2.7 cM region. Conclusion Two distinct resistance genes exist on the short arm of chromosome 1A as found in the two hard red winter cultivars, 2174 and Duster. Whereas the Hf resistance gene in 2174 is likely allelic to one or more of the previously mapped resistance genes (H9, H10, H11, H16, or H17) in wheat, the gene in Duster is novel and confers a more consistent phenotype than 2174 in response to biotype GP infestation in controlled-environment assays.