Evaluation of Wetting Front Detectors (WFD) for Irrigation Scheduling and Water Productivity; in Mychew Small Scale Irrigation Scheme (SSIS), Keih Tekli District, Tigray, Ethiopia

The principle “even a drop of water is matters” is essential for irrigation scheduling. Hence, this paper deals with three different methods of irrigation scheduling (Penman–Monteith equation, wetted front detector (WFD), and Modified Blaney – Criddle (B-C) (Modified B-C)) compared with farmer’s practices. The experiment was conducted in Tigray, Ethiopia, with the objective of evaluating WFD for irrigation scheduling. The experimental design was a randomized complete block design (RCBD). The collected data subjected to one-way analysis of variance (ANOVA), while irrigation water related performance indicators were computed using equations. The amount of irrigation water applied through estimated based on the Penman-Monteith equation, WFD, modified B-C method, and farmers practice (FP) were 510.3mm season-1, 489.6 mm season-1, 528.9 mm season-1 and 816.48 mm season-1, respectively. This indicated less irrigation depth was applied through WFD, and its irrigation interval was infrequent than the farmers' practices. The WFD method of irrigation scheduling revealed the highest yield and agronomic attributes of tomato. Additionally WFD had economic and productivity of irrigation water compared to farmers practice and other treatments. Likewise, this method of irrigation scheduling had saved 40% irrigation water over the farmers practice. As a conclusion, the WFD method of irrigation scheduling was found to be better for efficient irrigation water utilization while concurrently increasing tomato yield and yield components. More to the point, the method is easily manageable by farmers to properly manage their irrigation water. Accordingly, this irrigation-scheduling device is unreservedly recommended to be used for irrigation scheduling in the area.