An inbred cabbage line (Brassica oleracea L. (Capitata group))
and an inbred broccoli line (B. oleracea L. (Italica group)) were
crossed. F₁ progeny were vigorous annuals. Of 3,260 F₂ plants, 250
were biennials and 70 developed cabbage heads. Of these 70, 32 were
annuals. Days to first visible buds of...