Morphological variation among 78 local races of sour cherry (Prunus cerasus
L.) in the Nordic Gene Bank's Prunus clone archive in Palkane in Southwest
ern Finland was examined. Each tree was described using 42 characteristics.
On the basis of fruit characteristics, 32 samples were classified as morel
los, 40 samples as amarelles, and 5 samples distinct from the other amarell
es are proposed to be called Rymattyla-type cherries. One sample was found
to be Prunus avium. Amarelle type cherries proved to be more self compatibl
e than morello type cherries. In order to find hardy sour cherry cultivars
with fruits of good flavour and fit for cultivation in Nordic conditions, t
he most promising local races from each group were selected for a comparati
ve trial. Additionally, some local races were selected for further use in p
lant breeding. In 1994-1996, an increasing amount of severe bacterial canke
r symptoms was observed in the clone achive.