Significance and Possibility of Developing a Tree Joint Training System of Fruit Production

Abstract

Japanese pear (Pyrus pyrifolia Nakai) has been cultivated under a flat trellis for hundreds of years in Japan. Replanting trees in a traditional orchard is difficult because it takes a long time to establish a mature orchard due to the low tree density, which requires a long labor time and skills for pruning and fixing laterals on the flat trellis. We have invented a new planting and training system called the “Tree joint training system” to solve these problems by planting young trees linearly and connecting adjacent ones by grafting. The growth of horizontally connected stems and laterals is uniform based on the structural characteristics of this system. Advantages of this methods are: early high yield, reduction of labor time and easy tree management due to a simple tree structure. We monitored the translocation of water and assimilates among jointed trees, showing the standardized promotion of growth using this system. We came up with the idea in 1993, registered a patent belonging to Kanagawa Prefecture in 2012, and its use is now expanding in Japan. This innovative system has changed the traditional practices of training and pruning techniques and should be called a new high-density planting method, using neither dwarfing rootstocks nor root-control methods. This system has now been applied to various other fruit trees. In this application research, the “Joint V-shaped trellis system” is considered the best tree shape for mechanization. Currently, we are proceeding with experiments on mechanization and automatization, such as harvesting procedures.