Abstract:Three-year-old apple trees (Mlaus domestica Borkh.cv.Red Fuji) /SH/ Malus micromalus Makino were used in the present study to explore the effects of short-cutting on the dynamic changes of endogenous hormones. The results showed that the level of endogenous IAA in shoot tip and fine root was reduced. In the early vigorous growing period of shoots, the content of ABA in shoot tip ranked in the following order: heavy short-cutting > middle short-cutting > light short-cutting, which were 224.85 ng/g, FW, 204.95 ng/g, FW and 189.16 ng/g FW respectively. And no significant difference was observed between heavy short-cutting and the control. At vigorous growing period and slow growth period of shoots, the content of endogenous ABA in shoot tip and fine root of short-cutting was significantly higher than that of control, whereas the change of the level of ZR and GA showed no significant difference. The ratio of (IAA+GA+ZR)/ABA in shoot tip and fine root decreased along with the increase of pruning cut length.