Verification of a quantitative trait locus affecting agronomic traits in two-row barley

Quantitative trait loci (QTL) affecting agronomic traits have been mapped i n barley (Hordeum Fulgare L,), but there have been few experimental verific ations of the presence and effect of individual QTL. Here, we report on ver ification of a QTL on the "plus" arm of chromosome 7(5H) of barley. This QT L, affecting grain yield, plant height, maturity, and lodging severity, had been mapped in the two-row barley cross 'Harrington'/'TT306', on the basis of evaluation of 145 doubled haploid lines in 30 field experiments. We use d molecular marker genotypes to select 47 lines from among 410 Harrington/T R306 lines that had not been used in the original mapping experiment, Compa risons among groups of lines with contrasting marker genotypes on chromosom e 7(5H) confirmed that a QTL on the "plus" arm of that chromosome affects g rain yield, plant height, and lodging severity. The presence of TR306 allel es at this QTL, contributed to small increases in grain yield and plant hei ght, and reduced lodging severity. The results of this study confirmed the presence of a QTL affecting several agronomic traits, but also demonstrated that the effect of individual QTL may be small and may vary among environm ents.