Collard (Brassica oleracea L., Acephala Group) is a uniquely American cole crop adapted to the southeastern United States, and several lines of evidence indicate its closest relative is heading cabbage (B. oleracea, Capitata Group). These two cole crops have been grown in close proximity in the Southeast from colonial times. Today, the number of commercially available collard cultivars is limited, and the most popular ones are susceptible to diseases like fusarium yellows, something that numerous cultivars of cabbage are highly resistant to. We postulated that hybrids between cabbage and collard would look more like collard because heading of cabbage is recessive to the nonheading nature of collard, and that such hybrids might be directly used as collard cultivars that express disease resistance from cabbage. Cytoplasmic male-sterile (cms) cabbage inbreds were crossed with different male-fertile collard inbreds using bees in cages to produce hybrid seed. Resulting cabbage-collard hybrids were compared to conventional collard and cabbage cultivars in three replicated field trials in South Carolina. In all trials, collard-cabbage hybrids exhibited similar size and stature as conventional collard, and throughout most of the growing season the hybrids remained nonheading. In addition, the collard-cabbage hybrids were much more uniform than open-pollinated collard cultivars. Among the cabbage-collard hybrids there was significant variation with some more collard-like than others. Results indicate that select collard-cabbage hybrids could out perform certain conventional collards and serve as potential new collard cultivars
Collard (Brassica oleracea L. Acephala Group) is a leafy green vegetable adapted to the southeastern United States. The number of commercially available collard cultivars is limited, and the most popular cultivars are susceptible to fusarium yellows, a disease that most cabbage (B. oleracea Capitata group) cultivars are resistant to. We hypothesized that hybrids of cabbage and collard would look more like collard, because heading of cabbage is at least partially recessive to the nonheading growth habit of collard. We also postulated that cabbage–collard hybrids might be used directly as collard cultivars. To test these postulates, cytoplasmic male sterile cabbage inbreds were crossed to different male fertile collard inbreds and hybrid seed was produced. Resulting cabbage–collard hybrids were compared to conventional collard cultivars in three replicated field trials in South Carolina. In all trials, cabbage–collard hybrids exhibited size and weight more similar to conventional collard than cabbage, and throughout most of the growing season the collards remained nonheading. In addition, the cabbage–collard hybrids were much more uniform than open-pollinated collard cultivars. Among cabbage–collard hybrids there was significant variation with some hybrids appearing more collard-like than others. The collard inbreds designated A and B may have the greatest potential for making promising cabbage–collard hybrids. Particular hybrids (i.e., A3 or B2), derived from these inbreds and tested in this study, can perform better than certain conventional collards and may serve as possible new cultivars of this vegetable crop.