Development of Yellow Seeded Brassica napus Through Interspecific Crosses

Yellow seeded Brassica napus was developed through interspecific crosses with the two mustard species, B. juncea and B. carinata. The objective of these two interspecific crosses was the introgression of genes for yellow seed colour from the A genome of B. juncea and C genome of B. carinata into the A and C genomes of B. napus, respectively. The interspecific F₁ generations were backcrossed to B. napus in an attempt to eliminate B genome chromosomes and to improve fertility. Backcross F₂ plants of the (B. napus×B. juncea) ×B. napus cross were then crossed with backcross F₂ plants of the (B. napus×B. carinata) ×B. napus cross. The objective of this intercrossing was to combine the A and C genome yellow seeded characteristics of the two backcross populations into one genotype. The F₂ generation of the backcross F₂ intercrosses was grown in the field, plants were individually harvested and visually rated for seed colour. Ninety-one yellow seeded plants were identified among the 4858 plants inspected. This result indicated that the interspecific crossing scheme was successful in developing yellow seeded B. napus.