|LIU, MEIYAN - Jiangsu University
|LEI, LEI - Oklahoma State University
|POWERS, CAROL - Oklahoma State University
|LU, ZHIYONG - China Agricultural University
|CARVER, BRETT - Oklahoma State University
|YAN, LIULING - Oklahoma State University
Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2015
Publication Date: 11/25/2015
Publication URL: http://handle.nal.usda.gov/10113/63239
Citation: Liu, M., Lei, L., Powers, C., Lu, Z., Campbell, K., Chen, X., Bowden, R.L., Carver, B., Yan, L. 2015. TaXA21-A1 on chromosome 5AL is associated with resistance to multiple pests in wheat. Theoretical and Applied Genetics. 129:345-355. doi:10.1007/s00122-015-2631-9.
Interpretive Summary: Stripe rust of wheat has recently become a more widespread and serious disease problem across the world. A gene on the long arm of chromosome 5A in bread wheat was previously reported to confer consistent resistance in adult plants to predominant stripe rust races, but the precise identity of the gene not known. Comparative studies between wheat and rice identified a candidate gene called TaXA21-A1, which is very similar to a gene in rice that confers resistance to bacterial blight. TaXA21-A1 not only explained the variation in reaction to different stripe rust races but also showed significant effects on resistance to powdery mildew and Hessian fly biotype BP. Comparison of the characteristics of the TaXA21-A1 resistance gene from wheat and the corresponding resistance gene from rice may help elucidate the functions of these genes and lead to stronger and more durable resistance.
Technical Abstract: A quantitative trait locus QYr.osu-5A on the long arm of chromosome 5A in bread wheat (Triticum aestivum L., 2n=6x=42; AABBDD) was previously reported to confer consistent resistance in adult plants to predominant stripe rust races, but the gene causing the quantitative trait locus (QTL) is not known. Single nucleotide polymorphism (SNP) markers were used to saturate the QTL region. Comparative and syntenic regions between wheat and rice (Oryza sativa) were applied to identify candidate genes for QYr.osu-5A. TaXA21-A1, which is referred to as a wheat ortholog of OsXA21-like gene on chromosome 9 in rice, was mapped under the peak of the QYr.osu-5A. TaXA21-A1 not only explained the phenotypic variation in reaction to different stripe rust races but also showed significant effects on resistance to powdery mildew and Hessian fly biotype BP. The natural allelic variation resulted in the alternations of four amino acids in deduced TaXA21-A1 proteins. The interacting proteins of TaXA21-A1 were different from those identified by OsXa21 on rice chromosome 11 against bacterial leaf blight. TaXA21-A1 confers unique resistance against multiple pests in wheat but might not have common protein interactors or thus overlapping functions with OsXA21 in rice. Xa21 function has diverged during evolution of cereal crops.