S16 - Session P1 - Grafting type of Pi-Ku 1 rootstocks did not affect overall performance of sweet cherry trees

Authors: Martin Penzel *, Monika Möhler

Yield, average fruit mass and trunk diameter of either 'Sumbola' sweet cherry trees, grafted on Pi-Ku 1 rootstocks, originating from meristem (MPR) or hard wood cutting propagation (CPR), were compared over a period of 8 years starting from the third leaf. For trees, grafted on cutting-propagated Pi-Ku 1 rootstocks the trunk diameter 30 cm above the graft consistently exceeded those grafted on meristem-propagated rootstocks. Recorded in four of the eight years, the yield of CPR trees exceeded that of MPR trees in the sixth and the eighth year of the trees in the field, whereas yield was similar in the seventh and eleventh year. In the ninth and tenth years, frost events during bloom pronouncedly reduced yields. Mean fruit mass was the same on all tree-types in the four bearing years. In addition, soluble solids content, firmness and coloration was in the same range in fruit of both tree-types in the final year. Consequently, trees grafted on cutting-propagated Pi-Ku 1 rootstocks had a higher growth capacity compared to trees grafted on meristem-propagated Pi-Ku 1 rootstock, whereas rootstock propagation technique did not affect fruit yield consistently.