Yield-water relations and nitrogen utilization by wheat in salt-affected soils of Bangladesh

Abstract

Salinity is the most dominant factor limiting crop production during dry winter season (November–May) in the salt-affected soils of Bangladesh. Cultivation of salt-tolerant crop cultivars of wheat, barley and pulses with careful management practices can bring substantial change in the agricultural practice towards increased cropping intensity of the country. The 4-year experiments on wheat showed that grain increased by 28% with irrigation alone and by 35% with fertilizer only. Combined application of irrigation and fertilizer increased the yield by about 80%. N 15 isotope-aided studies indicated that the uptake of fertilizer N, Ndff and N utilization by wheat were, in general, considerably lower in the salt-affected soils. Water-use efficiency of wheat increased considerably with the application of fertilizers under both irrigated and non-irrigated conditions. No significant change in soil properties (e.g. pH, EC and CEC) was observed as a result of irrigation and fertilizer application. Continuous cropping, however, increased the total and fertilizer N uptake, %Ndff and %N utilization by wheat with considerable yield.