Virus elimination from ancient varieties of runner bean

In 2004, collected ancient varieties of runner bean were investigated in a cooperative project between the organic seed nursery Zollinger, the university of applied sciences Waedenswil, and the Agroscope Changins-Waedenswil Research Station ACW. The principal aim of this project, which is part of a national action plan of Swiss Confederation, was to preserve and promote biodiversity. Runner and dwarf beans (Phaseolus vulgaris) are infested with viruses very frequently. Virus infested plants show various symptoms such as dwarfing, misshapen leaves and beans, and yield depression. Viruses can be transmitted to the next generation by seeds and, as a consequence of that, infested varieties threaten to disappear. Within a tested assortment of 50 ancient varieties of runner bean 90% were infested with viruses. The Agroscope Changins-Waedenswil Research Station is carrying out elimination of viruses from infested varieties worth being preserved. During the last 3 years we succeeded in making 30 varieties virus-free and producing healthy seeds, which could be delivered to organizations engaged in this national action plan. These are breeders, propagators of vegetable seeds and the foundation “Pro Specie Rara”, who all are making efforts to promote biodiversity in fauna and flora.