Method of regulating apple seedling-plant transition stage

The invention relates to a method for regulating the seedling tree stage transformation of apple trees, which continuously measures and analyzes the contents of phloridzin, myricitrin and caffeic acid in the polythenol of different node samples, so as to determine the starting and finishing critical points of seedling tree stage transformation. Against the critical points, regulation measures can be used to the seedling trees to inhibit the nutrition growth, lower the inflorescence nodes for earlier blooming and fruiting, thus reducing the breeding cycle. In the second year after the seeding of apple seedling tree, the juvenescent phase is passed, while the stage transformation regulation is carried out in the fourth year; the apple trees bloom and fruit in the fifth year, and the initial selection of hybrid is finished in the seventh year, which is three years ahead of the time with the conventional technology and save 30 percent of breeding cost.