Abstract: [Objective] Our objective is to find out the media composition suitable for birch container seedling growth, through the comprehensive evaluation of the growth dynamic of above and underground parts, the biomass and the nutrient content of the container seedlings in different light media.[Method] We used four different light media as the main ingredients. They were edible fungus wastes, corn rotten straw, corn rotten core and peat soil, with supplementing an appropriate amount of humus of larch needles and vermiculite. Four media were mixed with those ingredients, namely edible fungus wastes+humus of larch needles and vermiculite (T₁); corn rotten straw+humus of larch needles and vermiculite (T₂); corn rotten core+humus of larch needles and vermiculite (T₃); peat soil + humus of larch needles and vermiculite (T₄). Additionally, the convenient nutrient soil served as control (CK). We measured the height, the diameter, the ratio of height to diameter, the leaf area, the biomass and the nutrition content of the seedlings in different media.[Result] 1) Over 70 days of continuous observation, we found that all the seedlings in the four light media containers had the same growth rhythm as the control. 2) After 70 days growth, the average height and the leaf area of the seedlings in T₄ were greatest, and 2.24 and 1.42 times of the control, respectively. The ground diameter of seedlings in all media from big to small was:peat soil (T₄) > corn core (T₃) > edible fungus wastes (T₁) > corn stem (T₂) > control (CK). The specific root length and the root number of the seedlings in T₁ were higher than the other media including the control (P<0.05). The biomass of seedlings in T₄ and T₁ were 2.24 and 1.42 times higher than the control, respectively. The quality index of seedlings in peat soil was best among the all media. The nitrogen content of seedlings from high to low was:corn core (T₃) > peat soil (T₄) > corn stem (T₂) > edible fungus wastes (T₁) > control (CK). The phosphorus content of seedlings in peat soil was better than the other media. The potassium content in seedlings had no significant difference among all media (P>0.05).[Conclusion] Peat soil was the best container medium than the other light media and the control. The seedlings in edible fungus wastes, the corn core, and the corn stem media were all growth better than those in the control. The edible fungus wastes media promoted the root growth significantly. As we know that peat soil consistently reduces in the world. Thus we suggest using edible fungus wastes as the light container medium, not only because it is easy to access, but also it has light weight and promotes root development.

Key words: Betula platyphylla, light media, container seedlings, edible fungus wastes, corn straw, corn core, peat soil