Selecting the favourite in a multi-year process is a major part of the breeding process headed by Markus Kellerhals. It starts with scab and fire blight resistance tests in a greenhouse, conducted by Lucie Franck, and molecular analyses and selecting seedlings in terms of their growth properties. Of the selected seedlings, one plant each is grafted on stock M27. Every individual plant gets a name and is designated a breeding number. Every year, new breeding numbers are planted and dug. The tree and fruit properties are identidfied in accordance with a rating scheme.
During the following stage A, 3 trees per breeding number are grafted on stock M9, Selection T 337, and tested. Stage A makes for interesting breeding numbers to be provided to VariCom's partners. Decisions by Agroscope and VariCom are taken jointly, on the basis of the test results, during the annual meeting in autumn and on the basis of the tasting of fruit samples in February, March. A defined nursery is growing trees for foreign test stations. Agroscope enters into experiment agreements with the test stations.
During stage B, 4 x 4 trees are planted. These sections of land are co-created and supervised by Simon Egger, Agroscope Variety Testing. Every 3 to 5 years, a new row is planted. The virus tests are conducted by Agroscope Certification, Markus Bünter. Any inclusion in the nuclear stock is decided upon by the Group Agroscope and Verband Schweizerischer Baumschulisten upon application by Agroscope Breeding, Markus Kellerhals. Extensive storage tests, various harvesting dates and storage variants of and for outstanding breeding numbers potentially to be launched into the market are then prepared by the fruits and vegetables working group at Agroscope Aftercrop, Franz Gasser and Jean-Pierre Siegrist.
During stage C, the test facilities in Güttingen, Thurgau on Lake Constance and Conthey in the Valais graft entire rows of trees on stock M9 T337. They serve as showcases for interested people from the trade, to get fruit samples, to conduct thinning and storage tests and to identify the total yield.