Development and Spread of New Variety of Japanese Wild Radish ‘Susanoo’ Using Regional Genetic Resources and Its Characterization

Abstract

With the aim of regional revitalization using a newly developed local cultivar, the new local pungent radish “Izumo Orochi Daikon”; ‘Susa-no-o’, with a distinctive root appearance and strong pungency, was bred from the genetic resources of wild radish (Raphanus sativus L. f. raphanistroides Makino) in the Izumo region of Shimane Prefecture. The improvement of the late bolting trait and resistance to mosaic disease were suggested in this cultivar as a result of repeating mass selections to achieve the breeding objectives. The seeds of ‘Susa-no-o’ after harvesting show a transition of germination rate similar to that of general radish. This cultivar can be evaluated as a high-functional radish with especially high free amino acid levels, isothiocyanate levels and 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidative properties compared with other cultivars. This local pungent radish, registered as a Shimane University brand, has gradually spread and been popularized in the region. Recently, it was recognized as one of the local varieties of Shimane Prefecture, and it has begun to contribute to regional agriculture and revitalization.