YIELD WATER RELATIONS AND NITROGEN-UTILIZATION BY WHEAT IN SALT-AFFECTED SOILS OF BANGLADESH

Salinity is the most dominant factor limiting crop production during d ry winter season (November-May) in the salt-affected soils of Banglade sh. Cultivation of salt-tolerant crop cultivars of wheat, barley and p ulses with careful management practices can bring substantial change i n the agricultural practice towards increased cropping intensity of th e country. The 4-year experiments on wheat showed that grain yield inc reased by 28% with irrigation alone and by 35% with fertilizer only. C ombined application of irrigation and fertilizer increased the yield b y about 80%, N-15 isotope-aided studies indicated that the uptake of f ertilizer N, Ndff and N utilization by wheat were, in general, conside rably 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 irrigatio n and fertilizer application. Continuous cropping, however, increased the total and fertilizer N uptake, %Ndff and %N utilization by wheat w ith considerable yield.