Root water uptake is strongly influenced by the morphology and anatomical structure of roots, which are regulated by nitrogen forms and environmental stimuli. To further illustrate the roles of different nitrogen forms on root water uptake under osmotic stress, a split-root system was supplied with different nitrogen forms and osmotic stress simulated by adding 10% (w/v) polyethylene glycol (PEG, 6000). The local effects of nitrogen form and osmotic stress on root morphology, anatomical structure, root lignin content, and water uptake rate were investigated. Under osmotic stress conditions, ammonium markedly promoted the formation and elongation of the lateral root, whereas a significant decrease in numbers of lateral roots was observed under local nitrate supply. Under nitrate supply in split-root systems, osmotic stress significantly promoted root cell death and more aerenchyma formation, as well as accelerated the lignification of the root. However, osmotic stress had no negative effect on the root anatomical structure under ammonium supply. The root water uptake rate was significantly higher in split-root supplied with ammonium than nitrate under osmotic stress conditions. In conclusion, the high water uptake ability in local ammonium supply was associated with the more lateral roots development and the lower cell death, aerenchyma formation and lignification under osmotic stress.

根系对氮的吸收主要受氮的形态和环境刺激调节。为了进一步说明不同氮素形式对渗透胁迫下根系水分吸收的作用，向分根系统提供了不同氮素形式和渗透胁迫，方法是添加10％（w / v）聚乙二醇（PEG，6000）。研究了氮素形态和渗透胁迫对根系形态，解剖结构，根系木质素含量和吸水率的局部影响。在渗透胁迫条件下，铵盐显着促进了侧根的形成和伸长，而在局部硝酸盐供应下，观察到侧根的数量显着减少。在分根系统的硝酸盐供应下，渗透胁迫显着促进了根细胞的死亡和更多的气孔形成，并加速了根的木质化。然而，在铵供应下，渗透胁迫对根部解剖结构没有负面影响。在渗透胁迫条件下，铵根供应的分根的根系吸水率显着高于硝酸盐。总之，局部铵供应的高吸水能力与在渗透胁迫下更多的侧根发育和较低的细胞死亡，气孔形成和木质化有关。在渗透胁迫条件下，铵根供应的分根的根系吸水率显着高于硝酸盐。总之，局部铵供应的高吸水能力与在渗透胁迫下更多的侧根发育和较低的细胞死亡，气孔形成和木质化有关。在渗透胁迫条件下，铵根供应的分根的根系吸水率显着高于硝酸盐。总之，局部铵供应的高吸水能力与在渗透胁迫下更多的侧根发育和较低的细胞死亡，气孔形成和木质化有关。