Interactive effect of nitrogen and potassium on nitrogen use efficiency in wheat

Wheat is moderately classified as a moderately salt tolerant crop. Appropriate use of nitrogen (N) and potassium (K + ) under salt stress condition considered as an effective approach to avoid N losses as ammonia (NH3) and to obtain improved nitrogen use efficiency (NUE).

In this study N and K application under normal and saline soil conditions were compared in a pot study under semi-controlled conditions. The results indicated that maximum NH3 losses (16%) were in saline soil on 2nd day of urea and calcium nitrate application. However, when K as potassium sulphate (SOP) or potassium chloride (MOP) was applied along with N sources apparent decline in NH3 losses (7%) was observed. Maximum increase in grain N content (3.61%) was observed under application of calcium nitrate with MOP in saline soil. The maximum increase in grain K+ content (3.05%) was observed under application of urea with SOP in normal soil. While, maximum NUE (30.89%) was observed under application of calcium nitrate with SOP in saline soil. It was concluded that application of N from any source of the two sources shoed better NUE with SOP or MOP application rather using alone in saline soil reducing ammonia losses.