New dwarfing and semi-dwarfing Pillnitz apple and pear rootstocks

The Pillnitz apple rootstock breeding program was concluded with the following results: 1. Three dwarfing rootstocks were submitted for breeder's rights Pillnitzer 'Supporter 1'(R): M.9 x M. baccata (L.) BORKH. Pillnitzer 'Supporter 2'(R): M.9 x M. X micromaltis MAKINO Pillnitzer 'Supporter 3'(R) M.9 x M. X micromalus MAKINO 2. Four semi-dwarfing rootstocks were prepared for application for breeder's rights: Pi-AU 36-2: M.9 x (M.9 x M. baccata (L.) BORK.) Pi-AU 51-4: M 4 open pollinated Pi-AU 51-11: M 4 open pollinated Pi-AU 56-83: M 11 open pollinated 3. The semi-dwarfing rootstock Pillnitzer 'Supporter 4'(R), a clonal selection of 'Pi 80', is presently multiplied in commercial nurseries. 'Pi 8W is a M.9 x M.4 progeny. Some results have been obtained with new Pillnitz pear rootstocks. The rootstocks are easy to propagate in stoolbeds, are more frost resistant against winter frost than quince rootstocks, and the growing capacity is inter-mediate between quince and seedling. They can be propagated by green cuttings and in vitro. Compatibility with several cultivars is satisfactory. Fruit quality of cultivars on these rootstocks is similar to quince.