Fruit quality variability within the tree canopy
We studied intra-canopy fruit quality variability as a function of flowering time and the age of the bud wood in apple trained to the spindle system. The experiment was carried out on adult 'Gala' apple trees grafted on M.9 rootstock. Three trees were chosen for the experiment and on these all the flower clusters were labeled just before bloom. The initial and final date of the king flower opening were recorded and for each of these, fruit diameter and ripening stage were monitored during the growing season. Also, the age of the wood carrying each flower cluster was recorded. At harvest, fruit size, over color and quality traits were assessed. Fruit variability within the canopy was very large. Flower opening time had a strong influence on fruit size and ripening stage. The first flowers to open were immediately characterized by a higher growth rate of fruits. At harvest these fruits reached a bigger size, an early ripening stage and lower flesh firmness. Moreover, a short flowering length also induced an earlier ripening. In addition the bud wood age had an effect on fruit quality and the flowers carried on older wood had larger size fruits, characterized by an earlier ripening stage and lower flesh firmness at harvest. There were no differences in either over color or in soluble solids content in fruits produced by different flower clusters and bud wood ages.
Dallabetta, N., Costa, F., Giordan, M., Guerra, A., Pasqualini, J., Wehrens, R. and Costa, G. (2017). Fruit quality variability within the tree canopy. Acta Hortic. 1177, 195-202
king flower, flower cluster, length of flowering, bud wood age, texture