Optimizing yield and irrigation water productivity of wheat under Sahel conditions in North East Nigeria

Unsustainable irrigation practices are a major threat to the available water resources and food security of the country. This research was conducted to determine the optimal wheat grain yield and water productivity (WP) under limited irrigation practices for the enhanced livelihood of small farmer holdings in the Sahel region of northeast, Nigeria. The research was carried out in randomized complete block design (RCBD) with split plot arrangement and replicated three times. The main plot treatment was 7 (I1), 10 (I2), and 14(I3) days irrigation intervals, while the subplot factor was 100 (V1), 85 (V2), and 70% (V3), of crop water requirement (ETc) replacement. The cropWat model was used to determine the crop water requirement (ETc) of the wheat (var. Norman) used in the research. The findings indicated that a 7-day irrigation interval increased grain yield by 20.18 over a 10-day irrigation interval and by 63.10% over 14-day irrigation intervals. Grain yield was found to decrease by 44.80 and 747.25kgHa-1 respectively for 85 and 70% ETc replacement irrigations from full ETc replacement irrigation. Crop water use efficiency was higher and better (0.74 mm-kg/ha) with I1V2 irrigation treatment for wheat and saved 11.55.50 m3 irrigation water over other irrigation schedules. It is recommended that 7 7-day irrigation interval be maintained, while irrigation depth can be reduced by up to 15% for optimum water productivity.