Abstract:

【Objective】 The aim of the experiment is to provide a theoretical basis for the extension of the branch bending technology in apple production. 【Method】Three-year-old apple trees (Malus domestica Borkh. cv Red Fuji)/Malus hupehensis grown in a pot were used in the present study to explore the effects of branch bending on growth of new shoots and the dynamic changes of endogenous hormones. 【Result】 The results were as follows: The level of endogenous ABA in shoot tip was positively conrrelated with branch bending, that of branch horizontal and branch drooping were 17.5% and 29.2% more than that of contorl at the first priord, but the level of GAs and IAA decreased significantly,and that of ZRs decreased unconspicuously. The level of endogenous ABA in fine roots of branch bending was significantly higher than that of contorl, whereas the level of GAs and IAA decreased in different extents, the change of the level of ZRs showed no significant difference. The ratio of (IAA+ GAs +ZRs)/ABA in shoot tip and fine roots decreased significantly along with the increase of branch bending angle, the values in shoot tip of contorl, branch horizontal and branch drooping were 2.11,1.61, and 1.36 respectively, at autumn shoot growing stage. 【Conclusion】 The level of endogenous IAA and GAs as well as the ratio of (IAA+ GAs +ZRs)/ABA decreased significantly after branch drooping.

Key words: Malus domestica, branch bending, endogenous hormones