The role of supplemental irrigation to crop water use under rainwater harvesting

Sorghum is an important food and dominant multi-purpose cereal crop in Sudan. Its production influenced by plant available soil water content at planting and growing season rainfall. Series of field experiments were carried-out to study the sorghum water use potentiality using different water harvesting techniques (WHT) and supplemental irrigation (SI). Soil moisture content (SMC), grain yield and water use efficiency (WUE) of sorghum were calculated during the years of 2012 and 2013. The results showed that the WHT and SI affected the SMC, growth and productivity parameters of sorghum. The results were also indicated that, the tied-ridging with SI (T1w) produced the highest values of SMC, sorghum productivity and WUE (10.59%, 3850 kg ha-1, and 0.71 kg m-3 in season 2012, respectively. Whereas in season 2013 the values were 11%, 4760 kg ha-1and 0.86 kg m-3 with the same arrangement mentioned above. Conclusively, the WUE could be promoted by implementing WHT as water stewardship. Nevertheless SI should consider as pivot factor that compensate the shortage in the rainwater