Novel Sources of Stripe Rust Resistance Identified by Genome-Wide Association Mapping in Ethiopian Durum Wheat (Triticum turgidum ssp. durum)

Frontiers in Plant Science

Roberto Tuberosa¹  Marco Maccaferri¹  Sheri Rynearson²  Michael Pumphrey²  Weizhen Liu²  Xianming Chen³  Habtemariam Zegeye⁴  Tesfaye Letta⁵ 

[1] Department of Agricultural Sciences, University of BolognaBologna, Italy;Department of Crop and Soil Sciences, Washington State University, PullmanWA, USA;Department of Plant Pathology, Washington State University, PullmanWA, USA;Ethiopian Institute of Agricultural ResearchAddis Ababa, Ethiopia;Sinana Agricultural Research CenterBale-Robe, Ethiopia;Wheat Health, Genetics, and Quality Research Unit, Agricultural Research Service (USDA), PullmanWA, USA;

关键词: wheat landraces;    Ethiopian tetraploid wheat;    association analysis;    yellow rust resistance;    90 K wheat SNP array;   

DOI  :  10.3389/fpls.2017.00774

来源: DOAJ

【 摘 要 】

Stripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is a global concern for wheat production, and has been increasingly destructive in Ethiopia, as well as in the United States and in many other countries. As Ethiopia has a long history of stripe rust epidemics, its native wheat germplasm harbors potentially valuable resistance loci. Moreover, the Ethiopian germplasm has been historically underutilized in breeding of modern wheat worldwide and thus the resistance alleles from the Ethiopian germplasm represent potentially novel sources. The objective of this study was to identify loci conferring resistance to predominant Pst races in Ethiopia and the United States. Using a high-density 90 K wheat single nucleotide polymorphism array, a genome-wide association analysis (GWAS) was conducted on 182 durum wheat landrace accessions and contemporary varieties originating from Ethiopia. Landraces were detected to be more resistant at the seedling stage while cultivars were more resistant at the adult-plant stages. GWAS identified 68 loci associated with seedling resistance to one or more races. Six loci on chromosome arms 1AS, 1BS, 3AS, 4BL, and 5BL were associated with resistance against at least two races at the seedling stage, and five loci were previously undocumented. GWAS analysis of field resistance reactions identified 12 loci associated with resistance on chromosomes 1A, 1B, 2BS, 3BL, 4AL, 4B and 5AL, which were detected in at least two of six field screening nurseries at the adult-plant stage. Comparison with previously mapped resistance loci indicates that six of the 12 resistance loci are newly documented. This study reports effective sources of resistance to contemporary races in Ethiopia and the United States and reveals that Ethiopian durum wheat landraces are abundant in novel Pst resistance loci that may be transferred into adapted cultivars to provide resistance against Pst.

【 授权许可】

Unknown