Historical cultivars of Allium cepa L. (Aggregatum-Group) introduced to Sweden 1830–1860

Abstract

This study presents the plant material of A. cepa L. Aggregatum-Group introduced and spread in Sweden between 1830 and 1860. The plant material exemplifies different principles regarding the denominations and shows the range of cultons available in the north of Europe by the time, but also examples of domestic local cultivars. It is essential to deepen the knowledge of the plant material and the name use connected to cultons spread in the nineteenth century. Historical records of old growing systems and propagation methods add valuable insights of the preservation values tied to the genetic diversity of the gene pool for future breeding. Differing practices and principles for distinguishing between potato onions, shallots and onions in European countries have sometimes made it difficult to understand historical records. The results of this study shows that shallot and potato onions, later mainly vegetatively propagated, were already in the nineteenth century occasionally propagated and spread by true seed in Europe. In addition, a Russian growing system with a true seed generation was found in literature. The article concludes that knowledge of older cultivation systems and introduction history deepens the link between the cultural-historical and the biological conservation values of plant material in long time preservation. Gene bank accessions may not only be valuable in breeding but also utilized and preserved as part of a biological or green heritage.