Conservation of radish genetic resources
Contributors to this page: CAAS, China (Qiu Yang, Li Xixiang); Bioversity International, Italy (Imke Thormann, Ehsan Dulloo); CGN, Netherlands (Noortje Bas); IPK, Germany (Andreas Börner, Ulrike Lohwasser); AVRDC, Taiwan (Andreas Ebert); USDA, USA (Larry Robertson); NBPGR, India (Chitra Pandey); SASA, UK (George Campbell); University of Warwick, UK (Charlotte Allender).
Importance of radish conservation
Radish has a long history of cultivation. It belongs to the cross-pollinated plant group with a self-incompatibility system. There are various types of radish landraces and traditional varieties with different sizes, shapes, colors, taste and other characters such as specific harvest and bolting dates, which have been developed through long domestication, evolution and breeding. Many are no longer favored types because consumption pattern and preferences have changed. Furthermore, radish needs vernalization for bolting and flowering. Therefore it is more expensive for farmers to produce seeds by seed to seed or root to seed methods than buying seeds at the market. The old radish landraces and varieties are replaced by modern, new radish varieties and are not cultivated any more. Wild radish species are threatened by ecological, climatic or human factors, or are already extinct. For example, there is no wild radish species in China although the crop has been recorded in the Chinese ancient books. Radish conservation is essential for the preservation of its genetic diversity and to help people use it in an efficiently and sustainable way for both the present and the future.
Major radish collections
It is estimated that there are more than 10,000 accessions of radish conserved in genebanks around the globe. The largest collections are held in China (> 2000 accessions) and Japan (> 1000 accessions), accounting together for nearly one third of the total accessions conserved worldwide. Germany, Russia, United Kingdom and United States of America all have collections with more than 500 accessions. Many of those accessions are varieties and landraces. Wild radish relatives are stored mainly in genebanks in Australia, Germany and Spain.