Abstract: [Objective] Harvest rotations are applied by foresters to reduce the length of the period of growing cycle for Houpoëa Officinalis culture. The aim of this study was to explore the effects of harvest rotations and growth time on growth and medicinal active ingredient content of Magnolia officinalis, and provide the theoretical basis for cultivation techniques. [Method] This study was conducted in M. officinalis. plantations with different rotations and stand ages in Anhua County, Hunan Province, and the growth performance, including tree height, diameter at breast height (DBH), bark yield, bark thickness and the accumulation of secondary metabolites such as honokiol and magnolol in bark were examined. [Result] The results showed that stumping significantly enhanced the growth rate of DBH, tree height and bark yield. The six-year-old plants with 1-2 rotations were similar in DBH, tree height and bark yield to the eight-year-old plants without rotation. Bark thickness was significantly and negatively correlated with rotations. The content of secondary metabolites accumulated rapidly after stumping, and the content in bark of 6-8-year-old plants with one rotation closed to that of 8-12-year-old plants without rotation. The accumulation of secondary metabolites in rotation 2 was significantly slower than generation one. The bark became thin and with low content of secondary metabolites after rotation 3 and then the root gradually decomposed. [Conclusion] The stumping method plays an important role in M. officinalis stand restoration which can facilitate the plant growth and secondary metabolite accumulation. This culture method can enable the forester profit earlier 3-4 years from M. officinalis cultivation.

Key words: Houpoëa officinalis, stumping, harvest rotation, growing time