Productivity and productive age of tree joint training system of Japanese pear as high-density planting cultivation without dwarfing rootstock

In areas of Japanese pear (Pyrus pyrifolia Nakai) production, tree vigor declining by tree aging and yield reduction have been issues, but replanting is necessary but not proceeding since it takes long years to establish a mature orchard and achieve enough income. “tree joint training system”, which Kanagawa Prefecture has invented is a high-density planting method without any rootstock and enables earlier establishment of a mature orchard and labor saving of management.
Now it is extending in areas of Japanese pear production as a new method of pear replanting.
In this study, we have experimented the growth, yield and fruit quality etc. of the original and oldest 26-year-old Japanese pear ‘Kosui’ trees by flat trellis joint training system in comparison with ‘Kosui’ by two scaffolds system of the same tree age since the invention of this training system.
Accumulated yield of 24 years since the first harvest in 1999 of ‘Kosui’ trees of tree joint training system was more than two scaffolds system by 135 t ha^‑1. The difference of accumulated yield between the two systems was due to the early high yield of tree joint training system.
Even at the age of 27, this system has not reached the limit of economical tree age because the latest yield of this system was 35 t ha^‑1. Number of new shoots of 27-year-old tree joint training system at the same distance from the main stem exceeded two scaffolds by 2 to 5 times.
Shoots near the tip of scaffold branch increased more than two scaffolds system.
In conclusion, as shown above, productivity of tree joint training system sustained at the age of 27 and productive age of the tree joint training system might extend longer than the two scaffolds in terms of yield and tree vigor.

IV Asian Horticultural Congress – AHC2023

K. Shibata, K. Hirose, T. Soneda, K. Katayama, T. Seki

Japanese pear, tree joint training system, productive age, fruit quality, replanting

https://doi.org/10.17660/ActaHortic.2024.1404.163