2023 Volume 22 Issue 2 Pages 155-162
As juvenile stage management suitable for the V-shaped orchard system of the columnar type apple Morioka No. 74, we investigated the effect of the number of scaffold branches on growth and the effect of gibberellin paste application. The number of scaffold branches was 2, 4, and 6. Gibberellin paste application was not applied to some of the trees with 4 scaffold branches. The application of gibberellin paste in the first and second years of planting promoted shoot elongation, and the amount of elongation in the 4 scaffold branch system was twice as much as that in the non-applied shoots. At the end of the second year of planting, more shoots reached the target length (300 cm) in the 2 scaffold branch system, however, more flower buds were formed in the 6 scaffold branch system. The number of flower buds was higher when the total growth of shoots in the first year of planting was greater, indicating that the application of gibberellin paste contributed to the increase in the number of flower buds. In the 6 scaffold branch system, completion of the tree form was delayed by one year compared with that of the 2 scaffold branch system, but the control of tree vigor is expected by producing fruits. These results suggest that the 6 scaffold branch system with gibberellin paste application is suitable for the V-shaped orchard system of Morioka No. 74/JM2.
