Genotyping-by-sequencing of Brassica oleracea vegetables reveals unique phylogenetic patterns, population structure and domestication footprints

Abstract

Which came first: the broccoli or the cauliflower? A comparison of gene variations in modern-day offspring of wild cabbage shows that broccoli may have preceded the appearance of cauliflower in domesticated crops. Jian Hua, Thomas Bjorkman, and colleagues from Cornell University in the US examined the DNA sequences of 85 traditional “landrace” and improved broccoli, cauliflower, and Chinese kale plants, all of which descend from the species Brassica oleracea, or wild cabbage. They found 21,680 sequence variations among them all, which they used to look for patterns of relatedness between the plants. Their results support the possible domestication of cauliflower after or in parallel with broccoli. The study identifies a large pool of genetic diversity within broccoli landraces that could be used to improve future breeding efforts.