Division of Soil Science and Agricultural Chemistry, Indian Agricultural Research Institute, New Delhi
In a loboratory study with N15, it was observed that prior addition of potassium and phosphate decreased retention of NH4-N in the alluvial soil of IARI farm to a large extent while in acidic alluvial soil from Dinhata, reduction was very little and in Pusa calcareous soil, retention either decreased or remained the same. In a pet experiment with wheat using IARI farm soil, same trend was observed in grain nitrogen and total recovery of nitrogen in grain and straw. In the calcareous soil from Pusa, the ammoniacal nitrogen remained in water-soluble form and was completely extract able with distilled water.
Retention of ammonium nitrogen, effect of potassium and phosphate
