Fig. 2

HvBot1 duplication is correlated with higher levels of HvBot1 expression. HvBot1 transcript levels (N = 6, ± sd) in barley roots of the parental genotypes Sahara 3771 and Clipper, and in HvBot1 segregant classes from an F₂ recombinant derived from a cross between two doubled haploid lines. Italicised letters above the bars denote significant differences between genotypes (Tukey’s multiple comparisons test; P = 0.05). The F₂ was identified as recombinant within the HvBot1 gene cluster, resulting in F₃ progeny with different numbers of copies of the Sahara HvBot1 allele. Southern analysis indicated that the homozygous recombinant progeny contained only a single copy of the Sahara HvBot1 allele. Seedlings were grown for 14 days in nutrient solution with an additional 2 mM B prior to sampling. F₃ individuals were genotyped using the closely linked xBM178 CAPS marker (S3 Table), to identify segregant classes