Abstract: The root samples of Pinus taiwanensis from seedlings to large trees of Mt. Huangsban were studied under light microscope(LM) and scanning electron microscope(SEN). It is obvious that ectomycorrhizae from extensively between the pine roots and the fungi. Isolation and pure culture of the samples of sporocarps were carried out, of which six strains were inoculated to the dissinfected seedlings were under laboratory condition. Pisolithus tinctorius was introduced to inoculate the pine seedlings too. Studies on the development of dichotomous mycorrhizae and the early stage of ectomycorrhizae formation were specially emphasized. Three types of the process of hyphae infection and the ontogeny of ectomycorrhizae synthesis, development and subsequent degeneration were described. Some ecological effects of ectomycorrhizae, which increase the growth of pine trees were also mentioned. Finally the authors sugge. st that the success inoculation of Pisolithus tinctorius to the pine trees will offer a new device for the formation and development of the ectomycorrhizae in terms to promote their growth.

Key words: Ectomycorrhizae, Pinus taiwanensis, Pisolithus tinctorius, Ecological relation