The Architectural Variation of Osmanthus fragrans Seedlings in Different Light Conditions

In this paper,crown shape,bifurcation ratios and leaves of Osmanthus fragrans seedlings were examined.The results showed that the architecture of seedlings was modified plastically in response to different light conditions.Because the seedlings that live in gaps get light intermittent,overall bifurcation ratio are significantly lower than that under canopy and full sun.Under full sun,the seedlings had their leaves distributed at the second-order branch with comparatively small length and area which can help seedlings use light fully.While,in gaps,seedlings seemed to have their leaves distributed at the first-order branch with comparatively large length and area to avoid being shaded by canopy.Under canopy,the leaves with small sum are distributed relative uniformly from the first-order branch to the third-order branch,and the height growth of branch is significantly higher than that under full sun.In conclusion,branching patterns of O.fragrans seedlings have unique traits: under strong radiation,O.fragrans seedlings can give rise to short branch and high bifurcation ratio.Under adequate shade condition they can give rise to long branch and low bifurcation ratio.Under intense shade condition they can give rise to comparatively long branch and comparatively high bifurcation ratio for height and horizon growth.