Utilization by maize of phosphonitrilic hexamide labelled with ¹⁵N at cyclic and at amino positions

Abstract

The phosphonitrilic hexamides (PNH) [¹⁵N₆] hexamino-phosphatriazine and hexaminophospha-[¹⁵N₃] triazine were synthesized. Vegetation experiments showed that PNH has a favourable effect on the maize growth. Also the results demonstrated that the major part of PNH is mineralized during the following days. This process diminishes after 60 days. The total N-fertilizer uptake is about 46%, 29% of which came from amino-N and 17% from cyclic N, respectively. PNH behaved as a slow releasing N-fertilizer.

Key Words:

• Fertilizer efficiency
• maize
• nitrogen 15
• phosphonitrilic hexamide (PNH)
• stable isotopes
• synthesis
• tracer techniques