Improving Onion Farming with Smart Irrigation: Using Wetting Front Detector to Boost Water Efficiency and Crop Yields in Northern Ethiopia
Friezer Debalkew *
Tigray Agricultural Research Institute, Axum Agricultural Research Center, P.O. Box, 231, Axum, Ethiopia.
*Author to whom correspondence should be addressed.
Abstract
Water scarcity and the decline in soil fertility remain the most limiting factors in intensifying agricultural production in the dry land agricultural system. A two-year field experiment was conducted at Hamedo and Hatsebo irrigation sites, Northern Ethiopia, aiming to introduce, evaluate, and promote of a relatively simple, accurate and practical irrigation scheduling technologies. In doing so, a field experiment was design and laid out in randomized complete block design (RCBD). Four factorial treatments (methods of irrigation scheduling Wetting Front Detector (WFD), Simple Calculation Method (SCM), FAO CropWat-8 Method (FAO), and compared with the standard check, farmer’s irrigation scheduling practice (FIP)) were evaluated with three replications. A combined analysis of the two-year (2020 and 2021) experiment was made for marketable Onion bulb yield (MYld), Water Productivity (WP) and other agronomic parameters such as bulb diameter (BD), bulb length (BL) and bulb weight (BW) using statistical software (R-software). The experiment result shows, in each experimental site (HAMEDO & HATSEBO), no statistical significant differences on BD, BL, BW at (P < 0.05), while, MYld, TYld shows significant differences in both locations. Compared with the standard check (FIP) scheduling practice the production and productivity of onion bulb (MYld) with (FAO, WFD, SCM) throughout the growing season application has shown significant differences at HAMEDO irrigation scheme. The higher IWP was observed with a scheduling method of WFD. On the other hand, a significant yield reduction of onion bulb (MYld) was observed at HAMEDO with the scheduling method of FIP and SCM. Based on this experiment, the wetting front detector (WFD) saved more than 15% of irrigation water compared to FAO CropWat-8 method at Hamedo irrigation scheme. Similarly, compared with the standard check (FIP) scheduling method the production and productivity of onion bulb (MYld) the WFD scheduling method has shown significant differences at HATSEBO irrigation scheme rather a relatively higher IWP was observed at SCM and FAO scheduling methods. In conclusion, the production and productivity of onion bulb (MYld) and irrigation water productivity is significantly affected with the proper scheduling practice in both locations. However, the effects on other yield parameters were not statistically significant throughout the treatments. The WFD scheduling method is a better option for sand clay loam soil textured at Hamedo irrigation scheme for optimum onion bulb (MYld) production and IWP. Therefore the technology is better to demonstrate at farmer’s level to increase farmer’s water management habit.
Keywords: Onion bulb yield, irrigation scheduling, wetted front detector, water productivity