Water use efficiency of barley as affected by irrigation regime, nitrogen and phosphorus fertilizers and sowing method

Two experiments conducted during three consecutive seasons 2003/04, 2004/05 and 2005/06, at Gezira Research Station to study the water relation, land productivity, water use efficiency, optimum irrigation interval, nitrogen, phosphorus and sowing method of barley. The treatments were three irrigation regimes every 10 days (Wl), 15 days (W2) and 20 days (W3) as main plot, three nitrogen levels 0 (0N), 96 (1N) and 192 kg urea/ha (2N) as subplot and two phosphorus levels 0 (0P) and 96 kg P2O5/ha (1P) as subsub plot in the experiment (1). The treatments of the experiment (11) comprised the same irrigation regimes as in the experiment (1) arranged as main plots and three sowing methods i.e. sowing by machine on flat in lines 20 cm a part (F), manual drilling on 60 cm a part ridges (R) and manual broadcast followed by 80 cm ridging (B) were the subplots. The design was RCBD arranged in split plot in both experiments, the replication were three in the experiment (1) and four in the experiment (11). The results indicated that the three years mean quantity of the applied water, for barley in Wl regimes were 5194 m3/ha and 4439 m3/ha in the experiments (1) and (11) respectively. The crop coefficients of barley at the initial, developmental, mid and late stages were 0.40, 0.92, 1.05 and 0.48. The fresh, dry matter and grain yields of barley in the three years in response to the irrigation regimes in both experiments were in a descending order of Wl, W2 and W3. The higher, fresh, dry matter and grain yields of barley in 2004/05 were attributed to lower day/night temperatures during the maximum growth period (30-75 DAS).The averaged WUEs of the irrigation regimes for the forage dry matter yield were Wl (1.12 kg/m3), W2 (0.97 kg/m3) and W3 (0.76 kg/m3). For the grain yields were Wl (0.34/m3), W2 (0.26 kg/m3) and W3 (0.22 kg/m3). Response of the forage and grain yield to N fertilization was highly significant. The effect of the P fertilization was significant only in the case of grain yield. In 2004/05 the highest forage yield in FM (19 t/ha) and DM (8 t/ha) were associated with Wl, IP and either of IN or 2N. While those of grain yield (2.0 t/ha) was associated with Wl, IP and IN. The higher forage yields of 2004/05 and Wl in the three seasons were paralleled with similar high growth attributes. Flat sowing proved to be a common high yielding method in term of forage where in term of grain was the 60 cm a part ridges