Association Mapping of Hagberg Falling Number in Hard White Spring Wheat

Hagberg falling number (FN) is an important quality trait used for grain grading. The FN test can only be measured in the late stages of variety development when progeny are homogeneous and sufficient grain is available for testing. The FN is strongly influenced by environmental conditions during reproductive growth stages, including excess moisture, extreme temperature, and biotic and abiotic stresses. The objective of this study was to identify potential genomic regions that influence FN in a subset of 110 hard white spring (HWS) wheat (Triticum aestivum L.) accessions from the National Small Grain Collection (NSGC) using genome-wide association mapping. The FN tests were conducted using grain flour samples of these accessions grown in five environments. A total of 1740 single nucleotide polymorphism (SNP) markers were used to detect SNP-FN associations using both the general linear model (GLM) and the mixed linear model (MLM). Thirteen quantitative trait loci (QTL) located in nine chromosomal regions were identified in both GLM and MLM approaches. Pyramiding these QTL could explain up to 45% of the phenotypic variation of FN. The present study identified several potential markers for use in marker-assisted selection for high FN lines in wheat breeding.