A new wild emmer wheat panel allows to map new loci associated with resistance to stem rust at seedling stage

• Autores: Mastrangelo, Anna Maria; Roncallo, Pablo Federico; Matny, Oadi; Čegan, Radim; Steffenson, Brian; Echenique, Carmen Viviana; Šafář, Jan; Battaglia, Raffaella; Barabaschi, Delfina; Cattivelli, Luigi; Özkan, Hakan; Mazzucotelli, Elisabetta
• Año de publicación: 2023
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: WILD EMMER; STEM RUST; GWAS; RESISTANCE; STRUCTURE
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Wheat stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is a major wheat disease worldwide. A collection of 283 wild emmer wheat [Triticum turgidum L. subsp. dicoccoides (Körn. ex Asch. & Graebn.) Thell] accessions, representative of the entire Fertile Crescent region where wild emmer naturally occurs, was assembled, genotyped, and characterized for population structure, genetic diversity, and rate of linkage disequilibrium (LD) decay. Then, the collection was employed for mapping Pgt resistance genes, as a proof of concept of the effectiveness of genome-wide association studies in wild emmer. The collection was evaluated in controlled conditions for reaction to six common Pgt pathotypes (TPMKC, TTTTF, JRCQC, TRTTF, TTKSK/Ug99, and TKTTF). Most resistant accessions originated from the Southern Levant wild emmer lineage, with some showing a resistance reaction toward three to six tested races. Association analysis was conducted considering a 12K polymorphic single-nucleotide polymorphisms dataset, kinship relatedness between accessions, and population structure. Eleven significant marker-trait associations (MTA) were identified across the genome, which explained from 17% to up to 49% of phenotypic variance with an average 1.5 additive effect (based on the 1-9 scoring scale). The identified loci were either effective against single or multiple races. Some MTAs colocalized with known Pgt resistance genes, while others represent novel resistance loci useful for durum and bread wheat prebreeding. Candidate genes with an annotated function related to plant response to pathogens were identified at the regions linked to the resistance and defined according to the estimated small LD (about 126 kb), as typical of wild species.
Fil: Mastrangelo, Anna Maria. Council for Agricultural Research and Economics; Italia
Fil: Roncallo, Pablo Federico. Universidad Nacional del Sur. Departamento de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina
Fil: Matny, Oadi. University of Minnesota; Estados Unidos
Fil: Čegan, Radim. Czech Academy of Sciences. Institute of Experimental Botany; República Checa
Fil: Steffenson, Brian. University of Minnesota; Estados Unidos
Fil: Echenique, Carmen Viviana. Universidad Nacional del Sur. Departamento de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina
Fil: Šafář, Jan. Czech Academy of Sciences. Institute of Experimental Botany; República Checa
Fil: Battaglia, Raffaella. Council for Agricultural Research and Economics; Italia
Fil: Barabaschi, Delfina. Council for Agricultural Research and Economics; Italia
Fil: Cattivelli, Luigi. Council for Agricultural Research and Economics; Italia
Fil: Özkan, Hakan. University Of Çukurova; Turquía
Fil: Mazzucotelli, Elisabetta. Council for Agricultural Research and Economics; Italia