Abstract Detail

Darwins' reversals: What we now know about Feralization and Crop Wild Relatives

Maggioni, Lorenzo [1].

Studies on domestication of Brassica oleracea L. point at possible feral status of European north-western Atlantic populations.

Domestication of Brassica oleracea L. gave rise to many different vegetable types (the cole crops), ranging from cabbage to cauliflower, broccoli, kohlrabi, Brussels sprouts, collard, etc. All these have the same C-genome with 2n=18 chromosomes, which is also shared with several (ten or more) wild species, mainly growing on limestone rocky slopes along the Mediterranean coasts. All these taxa are considered part of the so-called ‘B. oleracea group’ and can easily intercross, giving rise to hybrids with variable degrees of fertility, depending on the specific crosses. Several populations of B. oleracea grow in the wild on the Atlantic coastal cliffs of north-west Europe. It was Linnaeus who attributed the same name B. oleracea to the vegetable crops and to these Atlantic populations, thus implying that they belonged to the same species. The geographic origin of the domestication of the cole crops, and the corresponding wild relative from which they derived, have been unclear and controversial until now. Different theories have been proposed, including monophyletic or poliphyletic origins, involving either Mediterranean species and/or the Atlantic B. oleracea. A series of archaeological, linguistic, literary and molecular studies were considered to propose a north-eastern Mediterranean origin for the cole crops, at the same time supporting the belief that the Atlantic populations were originated through escapes from cultivation and re-naturalization of formerly domesticated brassicas. According to this line of thought, and based on reported observations, re-naturalization of B. oleracea appears to take place with a sudden loss of the domestication traits and quick return to wild habit and behavior, although the ongoing genetic events are not fully understood. Occurrence of re-naturalized B. oleracea on the coasts of California and New Zealand, far outside of the geographic distribution of any wild relative of the ‘B. oleracea group’, adds weight to the recognition of a special ability of this crop to return to the wild and to the theory of a Mediterranean domestication origin.

1 - Bioversity International, ECPGR, Via di San Domenico, 1 , Rome, 00153, Italy

Keywords:
domestication
Brassica oleracea
feralization.

Presentation Type: Colloquium Presentations
Session: C03, Darwins' reversals: What we now know about Feralization and Crop Wild Relatives
Location: /
Date: Tuesday, July 20th, 2021
Time: 10:15 AM(EDT)
Number: C03002
Abstract ID:549
Candidate for Awards:None