Abstract: | Pot experiments were conducted to examine the response of wheat to the timing of sulphur (S) application. Plants were fertilized at different Stages from sowing to the end of flowering. Plants grown without a basal S supply (severe deficiency), which showed deficiency symptoms at ear emergence, required fertilization with S at the tillering stage if yield losses were to be completely avoided. Moderate and slight S deficiency, which did not result in symptoms until after ear emergence, required rectification at the second node stage for full yield to be obtained. Treatment effects on yield were closely associated with effects on the number of kernels per ear. The results show that where S deficiency occurs, fertilization is required before symptoms become evident if yield reductions are to be avoided. |