Phosphorus and Sulphur Inter-relationships in Wheat (Triticum aestivum L.)

A pot culture study was conducted in an arid brown loamy sand low in available P and S status. Phosphorus and S application increased dry matter yield and their interaction effect was positive and significant. With P application, P content and total uptake increased and tissue S concentration decreased. Sulphur application increased P and S contents and total S uptake. Applied P significantly raised the per cent utilization of applied S and fraction of S in plant derived from the applied fertilizer. With increasing application of S, the uptake of fertilizer S and fraction of S in plant derived from the applied fertilizer increased, and the per cent utilization of fertilizer S decreased. S:P ratio in plants was wider at lower levels of applied P and it narrowed down with increase in P application. The dry matter yield tended to decrease when S: P ratio was less than 0.25 and was considerably reduced when this ratio was more than 0.75.