Influence of shoot architectural position on shoot growth and branching patterns in Cleyera japonica

摘要

The influence of shoot architectural position on shoot growth and branching patterns was examined in saplings of Cleyera japonica Thunb. (Theaceae), an understory, broad-leaved evergreen woody species. Shoot length varied with branching order and the vertical position of the branch in the crown. In the upper crown, shoot length decreased with increasing branching order, whereas in the lower crown, differences in shoot length among branching orders were not significant. These results demonstrate that it is important to consider not only individual shoots, but also the relationships between shoots in terms of their architectural positions when studying the development of crown architecture in trees. Shoot branching patterns also varied with branching order and the vertical position of the branch in the crown. In the upper crown, branching was mainly sylleptic. In the middle of the crown, mainly proleptic branches were produced. In the lower crown, there was little branching. The importance of these trends in shoot growth and shoot branching patterns in terms of carbon production efficiency is discussed.