Genome-wide association study for an efficient selection of Fusarium head blight resistance in winter triticale

Abstract

Fusarium head blight (FHB) is one of the most serious diseases in small-grain cereals including triticale (× Triticosecale Wittmack). The disease reduces yield and accumulates mycotoxins which are harmful to human and animal health. Triticale grain is almost exclusively used on-farm in feed formulations for swine and other animals, and swine is the most susceptible farm animal to Fusarium mycotoxins. In order to evaluate the potential of genomics-assisted breeding to FHB, we performed the first genome-wide association study for FHB resistance in triticale. QTL for FHB resistance were identified on chromosomes 2A, 2B, 5B and 3R with an explained genotypic variance ranging from 0.28 to 30.23% and a total explained genetic variance of 56.64%. A QTL on chromosome 3R that explained 15.38% of the genotypic variance was identified for the first time. Association mapping was complemented by genome-wide prediction, which yielded a high prediction accuracy of 0.78 for FHB resistance when weighted genomic selection was performed. Collectively our findings highlight the potential of genomics-assisted approaches to improve Fusarium resistance in triticale in early generations.