Abstract:To enhance the effects of ectomycorrhizal fungi to promote the growth of Korea spruce seedlings, based on previous research, the combinations of different ectomycorrhizal fungi strains were screened by dual culture method. 3 years transplanting seedlings of Korea spruce were inoculated by different combinations of ectomycorrhizal fungi strains using lister inoculating method in the field, and those were inoculated by different single strains were designed as control respectively. Thus the effects of different combinations and different single fungus strains to promote the growth of Korea spruces were studied. The results showed that all single strains and combinations in this experiment can promote the growth of Korea spruce seedlings. The growth characteristics of seedlings were observed 100 days after inoculation. The growth promoting effect of strain L15 was the best in all combinations and single strains. Comparing with control, the average height of seedlings inoculated by strain L15 was increased 30.88%, the average collar diameter of these was increased 15.29%. The growth promoting effect of combinations L15/025 or L15/009 were better than strain 009 or 025. Comparing with control, the leaf chlorophyll contents of seedling inoculated by strain 010 and combination L15/025 were increased significantly, the contents of chlorophyll a were increased 59.15% and 54.61% respectively, and the contents of chlorophyll b were increased 76.34% and 67.78% respectively. Except seedling inoculated by strain 010, the activities of hydrogen peroxidase of other treated seedlings were lower than one of control. The root activities of all treated seedlings were lower than one of control. In conclusion, inoculation by the mixture of high-effect strain and other single strain weakens the effect of high-effect strain to promote the growth of Korea spruce seedlings, the activity of hydrogen peroxidase and the root activity of seedling are not correlated with its biomass.