Abstract: Hoagland nutrient solutions with three Ca²⁺ concentration levels(5,10 and 15 mmol稬^-1)and a control(no Ca)were used to culture Pteroceltis tatarinowii seedlings.The results indicated that in the control,most seedlings were dead and the survived seedlings were grown poorly,while in three Ca²⁺ concentration treatments,there were no significant differences in seedling height growth and biomass by the end of the experiment.The Ca content in the root,leaf and bark of Pteroceltis tatarinowii increased with increasing Ca²⁺ concentrations,and ranked as root>leaf>bark.Ca treatments had no significant effects on the wood and bark density and the fiber shape traits of one-year seedlings.However,the wood fiber length was the longest and the wood fiber width was the widest at the 10 mmol稬^-1 Ca²⁺ concentration treatment,while the bark fiber length and the ratio of fiber length to fiber width were the best at the 5 mmol稬^-1 Ca²⁺ concentration treatment.Among the three Ca²⁺ concentration treatments,the bark fiber length was over 2 mm,and the ratio of fiber length to fiber width was much higher(about 4 times) than that of the wood.There was a significant difference in cellulose contents of wood and bark of one-year seedlings among the three Ca²⁺ concentration treatments,and the highest cellulose content was achieved at the 10 mmol稬^-1 Ca²⁺ concentration treatment.These results provided some information for the improvement of the growth and bark quality of Pteroceltis tatarinowii grown on non-limestone soil.

Key words: Pteroceltis tatarinowii, Ca²⁺ concentration, Height growth, Biomass, Bark quality