| Setzer, B; Gebauer, G; Mohr, H: Die Bedeutung der Kaliumversorgung für Aufnahme und Assimilation von [15N-]Nitrat und [15N-]Ammonium durch Keimpflanzen der Kiefer (Pinus sylvestris), Allg. Forst- u. Jagd-Zeitung, 169, 76-80 (1998) | |
| Abstract: In the present study with Scots pine seedlings the interaction between nitrate/ammonium - and potassium nutrition was studied with the help of labelled nitrogen (15N). The major results are as follows: The seedlings absorb ammonium much more readily than nitrate. Optimum potassium supply leads to a higher protein content. This effect is to be attributed to an increased assimilation of nitrate and endogenous N-storage compounds. Potassium stimulated protein synthesis corresponds with a decrease of soluble N-containing compounds. Reduced potassium supply leads to the consequence that the additionally absorbed ammonium is incorporated in soluble N-containing compounds. The previously described alleviating effect of potassium on ammonium stress in coniferous seedlings is explained by the potassium mediated decrease of ammonium incorporation.-While uptake of nitrate is independent of potassium supply, ammonium uptake is reduced in the presence of potassium. |
