Figure 5.

Illustration of the 22 kb CBF2A–CBF4B genomic region copy number variable unit. Top depicts the Morex-like spring allele. Middle shows the Nure allele as determined from sequencing BAC clones [137], which is predicted to be representative of current winter malting barley lines based on sequencing, DNA blot hybridization, pedigree, or any combination of these [100]. Lower allele depicts hypothesized Admire allele, which were estimated by DNA blot hybridization and following the structural organization pattern revealed by Mareri et al. with the centromere toward the north on the vertical illustration and left on the horizontal illustration [135,137]. Other MO B lines possess copy numbers that are intermediate between Admire and the Dicktoo-Nure allele [135]. The colored ovals are used to illustrate a common region across genotypes outside the iterated 22 kb CBF2A–CBF4B genomic region. For example, the green oval identifies a region containing a Xba I site that is common across genotypes having the Dicktoo-Nure allele, which is 6.0 kb from an Xba I site in the iterated region. Using a CBF4 coding sequence probe on an Xba I digest in DNA blot hybridizations results in a single copy 6.0 kb MW fragment, and a multi-copy 9.3 kb fragment.