Abstract
Two Japanese varieties (Shinchunaga and lgachi-kugo) of Triticum aestivum ssp. vulgare (AABBDD, 2n=42) were crossed with pollen of T.polonicumvar. vesticum (AABB, 2n=28). In 1952 the pentaploid F1 hybrids were grown, and their progenies were raised by self-pollination or backcrossing to the common wheat parents. Through successive generations tetraploid plants with the least resemblance to T. polonicum were selected fcr the purpose of obtaining plants with 28 chromosomes (AABB) from the common wheat parents. The pedigrees are shown in Tables 1 and 2.
