The large bread wheat genome (1C approximately 17 Gbp) contains a preponderance of repetitive DNA and the species is polyploid. These characteristics together serve to hamper the molecular analysis of the wheat genome. Its complexity can, however, be reduced by using flow cytometry to isolate individual chromosomes, and these can be exploited to construct chromosome-specific BAC libraries. Such libraries simplify the task of physical map construction, positional cloning and the targeted development of genetic markers. Rapid improvements in the efficiency and cost of DNA sequencing provide an opportunity to contemplate sequencing the wheat genome by preparing sequence-ready physical maps for each chromosome or chromosome arm in turn. The quality of the chromosome-specific libraries depends on their chromosome coverage and the mean insert size. First-generation libraries suffered from a relatively low mean insert size, but improvements to the protocol have generated a second wave of libraries with a significantly increased mean insert size and better chromosome coverage. Each chromosome (arm)-specific library is composed of a manageable number of clones, and so represents a practical tool in the area of wheat genomics.

Laboratory of Molecular Cytogenetics and Cytometry Institute of Experimental Botany Olomouc Czech Republic

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Extracts from the leaves of knotweeds (Reynoutria spp.) have a stimulating effect on the germination and initial growth of wheat grains

Flow Cytometric Analysis and Sorting of Plant Chromosomes

Chromosome analysis and sorting

Evolution of multiple sex-chromosomes associated with dynamic genome reshuffling in Leptidea wood-white butterflies

Aegilops umbellulata introgression carrying leaf rust and stripe rust resistance genes Lr76 and Yr70 located to 9.47-Mb region on 5DS telomeric end through a combination of chromosome sorting and sequencing

Features of the organization of bread wheat chromosome 5BS based on physical mapping

Rapid cloning of genes in hexaploid wheat using cultivar-specific long-range chromosome assembly

The in silico identification and characterization of a bread wheat/Triticum militinae introgression line

BioNano genome mapping of individual chromosomes supports physical mapping and sequence assembly in complex plant genomes

A High Resolution Radiation Hybrid Map of Wheat Chromosome 4A

A high-resolution physical map integrating an anchored chromosome with the BAC physical maps of wheat chromosome 6B

Chromosomal genomics facilitates fine mapping of a Russian wheat aphid resistance gene

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The physical map of wheat chromosome 5DS revealed gene duplications and small rearrangements

Characterization of repetitive DNA landscape in wheat homeologous group 4 chromosomes

High-throughput physical map anchoring via BAC-pool sequencing

New insights into the wheat chromosome 4D structure and virtual gene order, revealed by survey pyrosequencing

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Intraspecific sequence comparisons reveal similar rates of non-collinear gene insertion in the B and D genomes of bread wheat

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