Abstract
Origin and development of adventitious roots in cuttings of Thujopsis dolabrata were observed. Roots arose from stem tissues near the cat base (Fig. 3) and from callus tissues (Fig. 4).
Most of roots from stem tissues initiated in the cells of phloem region of primary ray tis sues immediately below the ieaf trace (Fig. 5), developing in rather elongated shape (Fig. 7) as compared with Cryptomeria cuttings formerly observed (1), and the others arose in connection with leaf traces (Fig. 9, 10).
Roots from callus tissues developed as a group of meristematic cells in connection with the differentiating callus xylem (Fig. 11).
Only one root seemed to arise from the parenchymatous phloem layers, connecting with newly formed xylem near the cut base (Fig. 12).
Distribution of root primordia among tissues from which roots- arose, increase in the number of root primordia and roots from 10th to 64th days after planting are shown in Table 1, 2. respectively.
