REVERSION IN SPUR CLONES OF DELICIOUS AND GOLDEN DELICIUOS APPLE TREES
All the mother trees, now 17 years old, are still under observation for the stability of the spur phenotype. Regressed trees (5 out of 10) were found, after 1972, only in Starkspur Golden Delicious. After 10 years the spur habit is consistent only in the 7% of the trees originated from regressed trees while in the 91% of the trees originated from spur trees.
Regression appears more frequently in Golden Delicious than in Delicious. Buds originating regressed V1 trees were distributed: .46% in the basal third of the original budstick, 26% in the central and 28% in the apical.
A carefull selection of mother plants in the nursery has to be suggested.