The genome approach in radical wheat breeding

The transfer of desirable characteristics to hexaploid wheats from tetraploid wheats, Agropyrons, and rye has been reported by various investigators. The diploid wheats (einkorns) and the genera Aegilops and Haynaldia also have attributes which would be very useful if transferred to hexaploid wheats. The A genome of hexaploid wheats is evidently derived from einkorn, the C from Ae. squarrosa, and the B perhaps from Agropyron. The best chance of transferring desirable characters from einkorn is assumed, therefore, to be to the A genome, from Agropyron to the B genome, and from Aegilops to the C genome. To overcome sterility and other difficulties, four series of artificially produced allohexaploids, the first two of which are partially completed, are suggested as basic material for the transfer of characters from other species and genera to T. vulgare as follows: 1. Amphiploids of Ae. squarrosa with various tetraploid wheats for transfer of characteristics from the tetraploids to the A and B genomes. 2. Amphiploids of tetraploid wheats with various diploid species of Aegilops for transfer of Aegilops characters to the C genome. 3. Amphiploids of the A+C combination (einkorn X Ae. squarrosa) with various species of Agropyron for transfer of Agropyron characters to the B genome. 4. Amphiploids of the constitution BBCC (if obtainable) plus various species and varieties of einkorn, for transfer of einkorn characters to the A genome. The following amphiploids are described: T. dicoccoides X Ae. squarrosa, Ae. caudata, Ae. comosa, Ae. sharonensis, Ae. speltoides, Ae. umbellulata, Ae. uniaristata, and Haynaldia villosa; T. dicoccum and T. persicum X Ae. sharonensis; T. timopheevi X Ae. squarrosa, Ae. bicornis, Ae. caudata, Ae. speltoides, Ae. umbellulata, and Ae. uniaristata.