Figure 2

'Pooling noise': the effect of bulk sizes on the amplitude of spurious linkage signals. Genome-wide significance thresholds for detecting spurious linkage between a marker and a target locus were derived from 10,000 simulated comparisons between bulks of F₁-derived DH barley plants (see section entitled 'Allele-frequency determination and simulation' in Materials and Methods for details). Trait-linked markers should only be considered as statistically significant if the allele-frequency difference between bulks is superior to the value derived for the relevant combination of bulk size and desired probability level.