A wide collection of wild emmer accessions to recover novel diversity for yellow rust resistance

MAZZUCOTELLI E; MATNY O; MARTIN M; STEFFENSON B; RONCALLO P; ECHENIQUE V; DESIDERIO F; BARABASCHI D; BATTAGLIA R; CAKIR E; OZKAN H; CATTIVELLI L; MASTRANGELO AM

Bologna

Conferencia; From Seed To Pasta III; 2018

Avenue Media

The stripe or yellow rust (YR) disease, caused by Puccinia striiformis f. sp. tritici (Pst), severely threatens grain yield. Unusual and severe epidemics of YR were observed on several continents in 2017 and years before, including not endemic geographic area, as a consequence of climate changes. Urgent is the exploration of new genetic variability to discover novel resistance genes. Alleles of the wild emmer wheat (T. dicoccoides), progenitor of the domesticated durum wheat, have been introgressed in cultivated wheat and showed to positively contribute to biotic and abiotic stress tolerance, yield components and quality. Among a wide collection of wild emmer accessions established c/o CREA-Genomics and Bioinformatics Research Centre, 285 geo-referenced lines have been genotyped using the Axiom 35k array, obtaining about 12000 poly-high resolution SNPs. The collection includes accessions originated from all Fertile Crescent countries, thus representing all environments where wild emmer naturally occurs. The assessment of genetic diversity and population structure identified two well-defined groups, mostly corresponding to the two known races, as well as subgroups, according to the originating geographic area. A genome-wide critical distance around 0.5Mb was found for LD decay (r2).