Transmission of chromosomes through the eggs and pollen of triticale × wheat F1 hybrids.

The substitution patterns of rye chromosomes in hexaploid triticale × wheat F2 hybrids, along with the transmission patterns of rye chromosomes through egg cells and pollen when several of the F1 hybrids were test crossed to triticale and wheat were investigated. The data indicated that the rye chromosome transmission through both the egg and pollen was random in number and in composition. The test crosses suggested that it was best to use wheat pollen for the transmission of rye chromosomes through the egg cells of the F1 hybrids and triticale egg cells for the transmission of rye chromosomes through F1 hybrid pollen. A deviation from random segregation in the F2 and the transmission rate was observed for rye chromosomes 1R, 4R/7R, and 6R. The transmission rates of 1R and 6R varied depending on the direction in which the cross was made. The results also indicated that there was little or no compensation between the R- and D-genomes and that the chromosomes of these two genomes appeared to be transmitted independently of each other.