The invention discloses a rapid updating and rejuvenation method for a tree body weakened by apple rot. The rapid updating and rejuvenation method comprises the following steps: digging off soil around a
trunk of the tree body in the last ten-day period of March so as to
expose a first
root system base part, spraying a bactericide to the root of the
trunk, and backfilling the soil; sawing the treebody from
a site which is 3cm-5cm from the ground, and carrying out
grafting at a saw kerf; selecting a main head according to the height of a scion, removing a sprout, and carrying out
twig drawingand angle opening; selecting a scion
twig as a permanent tree body to be cultured in the middle ten days of August,
grafting the other two scions to the permanent tree body; carrying out pinching on the main head in the middle ten days of September; completely releasing the twigs during the trimming so as to enable the twigs to naturally extend in a single-shaft manner, and selecting main twigs which are distributed in a spiral rising manner; carrying out
bud notching and
twig promotion; removing buds on the backs of the main twigs, and carrying out twig drawing and angle opening; and carryingout fertilization and sterilization. According to the rapid updating and rejuvenation method for the tree body weakened by apple rot, the
frequent use of a large number of chemical pesticides is avoided, the defects caused by the scraping of diseased
scars are overcome, and the rapid updating and rejuvenation of the weakened tree body are realized only through underground healthy roots.