Abstract: This paper is studied the inoculation for development of ectomycorrhizae on container-grown tree seedlings of some commercially important Chinese tree species with two different types of inocula of the ectomycorrhizal fungus Pisolithus tinotorius (P_t). Results show that the inoculation of these tree species tested is successful with solid-base cultures of mycelium of this fungus. Excellent P_t, ectomycorrhizal root de velopment (P_t index 70⁺ and P_t ectomycorrhizal percentage 95%) is produced on the seedlings of the four pines tested. The typical (large, swollen, golden, bifurcate) P_t ectomycorrhizae observed on these four Chinese species are identical to those observed on Loblolly Pine. It confirms that like Loblolly Pine these pine species are hosts of P_t fungus and implys that there is a great potential to use the techniques for development of ectomycorrhizae on these species in forest production. However, spore pellet inoculum is considerably less effective (P_t index 10 and P_t ectomycorrhizal percentage<20%). No ectomycorrhizae on Chinese Fir, Chinese Arborvitae and Siberian Eim are observed in this experiment. This suggests that these species most likely are endomycorrhizal or/and facultative ectomycorrhizal tree spectes. Besides, this study also provides techniques and methods for development and evaluation of ectomycorrhizae on container-grown tree seedlings for forest research and production in China.

Key words: Ectomycorrhizae Pisolithus tinctorius inocula, Pinus tabulaeformis, Pinus massoniana, Pinus yunnanensis