At higher nitrate supply, root elongation of 478 was inhibited, the distance from the site of lateral root elongation to root tip became shorter, the root cap became shorter, and root elongation zone became swollen.

• 在高浓度NO_3~-供应条件下,478根伸长显著缩短,侧根发生部位距根尖的距离变短、根冠变薄,根伸长区膨大。