ABSTRACT
To execute the afforestation and revegetation for the protection of environment, the techniques for raising good seedlings are required. Seedlings of camphor tree, a broad-leaved tree, were used in this experiment. From August to January, the growth characteristics of the seedlings were observed under different conditions of light intensity and soil moisture content in a plastic house.HomePage
The changes of total dry weight, leaf area and leaf dry weight ware well fitted to simple logistic curves. Under shading(ca.29% of control), the dry matter production, absolute growth rate and relative growth rate (RGR) increased compared with those of control; these were ascribed to the characteristics of camphor tree. The top growth was also accelerated due to the sufficient partitioning of photoassimilate to leaf fraction. According to the growth analysis, the adaptation form of camphor tree seedlings to shading was interpreted as the 'stress avoidance' in which the leaves became thin and large. While, under conditions of low soil moisture, RGR decreased because the top growth was restricted. This adaptation form was the 'stress tolerance' in whichi the dry matter partitioning to root increased.Keywords:camphor tree, seedling, light intensity, soil moisture content, logistic curve, absolute growth rate, relative growth rate, growth analysis