Growth and production of adult Japanese persimmon (Diospyros kaki) trees grafted onto dwarfing rootstocks

• Japanese persimmon trees on MKR1 of 10-year-old and more showed a dwarfing habit.
• The trees on MKR1 continued to increase number of flowers and percentage of flower-bearing shoots.
• The yield efficiencies of the trees on MKR1 were the highest.

The field performance of adult ‘Fuyu’ and ‘Hiratanenashi’ Japanese persimmon (Diospyros kaki Thunb.) trees grafted onto D. kaki seedlings (S), Rootstock-a (R-a), and MKR1, as well as own-rooted trees, which were planted in February 2003, was investigated. The height of trees grafted onto MKR1 did not increase after 2010, although the other trees grew vigorously. All trees increased annually in number of shoots, but this was not the case for mean shoot length. Trees grafted onto MKR1 continued to increase in number of flowers and percentage of flower-bearing shoots, whereas the number of flowers and percentage of flower-bearing shoots did not increase each year in most of the other trees examined. The fruit yield per tree did not markedly differ between rootstocks except for in ‘Hiratanenashi’ on S. However, the yield efficiencies of the trees grafted onto MKR1 were the highest in total, even when the tree was over 10 years old. There were no consistent trends in fruit quality between rootstocks, except for fruit weight in ‘Fuyu’, where the trees grafted onto R-a produced lighter fruit. The shelf life of ‘Fuyu’ fruit grafted onto MKR1 was not different from that of the trees grafted on the other rootstocks. These results indicated that trees grafted onto MKR1 produced normal, commercial fruit. Although the mechanism by which MKR1 causes dwarfing in persimmon trees remains unknown, these results allow us to conclude that MKR1 is a practical dwarfing rootstock for easy-to-manage orchard system of Japanese persimmon.