Abstract

A fertigation experiment was conducted during 2009/2010 and 2010/2011 seasons under com-mercial field conditions in Kenana Sugar Scheme, Sudan (latitude 13.10’N and longitude 32.40’E) in heavy clay soils, with 65% clay, 24% silt, 11% sand and pH 7.5 - 8.5. The primary objective of this study was to compare different strategies for timing of injection, to develop management practices on the efficient use of water and fertilizers in production of sugarcane, maximize yield, and improve quality. In both seasons four treatments were studied in a randomized complete block design with three replications as: Injection of the dissolved urea (46% N) during entire irrigation time (100%), during the first half of the irrigation time, during the second half of the irrigation time, and Mechanical application of urea. The first three treatments were applied with the third irrigation cycle through the irrigation water so that nitrogen fertilizer in form of dissolved urea (46% N) was injected in irrigation water by means of pressure differential tank system which is based on the principle of a pressure differential being created by a valve and flow regulator forcing and injecting a varying amount of dissolved fertilizer into the irrigation water. In the fourth treatment the fertilizer spreader and rigid tine cultivator were used for urea application just before the third irrigation event. The reference evapotranspiration (ETo) and the amount of water required for irrigating sugarcane plants were calculated according to its phenological stages using Peman-Monteith approach. The results of this study support the general finding that the injection during the entire irrigation (100% of the irrigation) produced the best distribution uniformity of added urea. In this study, injection during the first half of the irrigation was not statistically different from injection during 100% of the irrigation. EWW140918DXN