s: Effects of total alkaloids of Sophora alopecuroides (KSH) on growth of height and trunk diameter of one year old poplar trees (I-69)were studied by trunk injecting 6mL\5kg -1 of the testing tree weight. The net growth of trunk diameter at ground level of the treated trees, which were injected with KSH at 2×10 -2 , 1 7×10 -2 ,5 8×10 -3 mol\5L -1 , increased significanly and statistically in comparison with that of the control, and there was close positive correlation between the KSH concentration and the net growth of the trunk diameter. Growth of the tree height only shown in the concentration of 5 8×10 -3 mol\5L -1 , which was significantly and statistically increased in comparison with that of the control. The net growth of the tree height was inhibited in the groups at 1 1×10 -5 , 5 5×10 -5 , 2 8×10 -4 mol\5L -1 of NNA, whereas the net growth of trunk diameter at ground level of the treated trees treated with NNA shown significantly increase only at the lowest concentration of 1 1×l0 -5 mol\5L -l .The net growth of the tree height and the net growth of trunk diameter were promoted and inhibited respectively at the concentration of 2 9×10 -5 mol\5L -1 of GA. The results of the experiments with three years poplar trees indicted that injecting KSH of 5 8×10 -2 mol\5L -1 could significantly stimulate the net growth of trunk diameter at ground level of the treated trees during the testing period. The results of measuring the wood grown in the experiment period shown that there was no significant difference between the basic density of the treated wood and that of the control. It indicated that treatment of KSH could not only accelerate tree growth, increase significanfiy wood volume, but also there was no significant decrease in weight of dry materials.
