Effects of ammonium on primary root growth.

Root growth parameters were analyzed kinematically at five days after treatment, as described in the methods. Values in parentheses are the percentage of control. Data represents as means ± SE (n = 6–7).如实验方法部分所述，于处理后第5天对根系生长参数开展运动学分析。括号内数值为相对于对照组的百分比。数据以平均值±标准误（Standard Error, SE）表示，样本量n=6~7。