Physical mapping of a male-fertility gene of common wheat.

A terminal deletion in the short arm of chromosome 4B was obtained in the progeny of an alien monosomic addition line of common wheat (Triticum aestivum (L.) emend. Thell) with a chromosome from Aegilops cylindrica Host. Common wheat plants homozygous for the deletion were completely male sterile. The breakpoint was at about 84% of the length of the short arm from the centromere. Therefore, the male-fertility gene was located in the distal 16% region of the chromosome 4B short arm. This terminal deletion practically suppressed meiotic pairing between the short arms of the normal 4B and the deletion 4B chromosomes.