Association mapping of yield and some important agronomic traits in barley (Hordeum vulgare L.)

In order to detect QTLs for yield and some important agronomic traits via association mapping, 100 cultivars of winter barley (Hordeum vulgare) were evaluated in a lattice design with two replications. Yield, kernel per spike, thousand kernel weight, heading date, harvest index and plant height were measured. The population was genotyped using 3964 SNPs with minor allele frequency (MAFs) more than 10 percent. Molecular analysis of the population structure appeared two subpopulations consistent with ear row number. Average LD was observed to decay with distance increase and in the subpopulations was more than of that in the whole genome. Using a mixed linear model with kinship for controlling spurious LD effects, a total of 103 significant marker trait associations were found. 47 of the significant associations had previously been reported and 56 QTLs were reported for the first time. SNP_3660 linked with the yield and SNP_1432 associated with the kernel per spike, the thousand kernel weight and the spike morphology (two rows and six rows) had maximum -Log P and could be considered for marker assisted selection. This study showed that association mapping is a powerful tool for quantitative trait loci localization.