Abstract:
Exploring options to access
water for irrigation and water management
strategies at the field level is pivotal for
improving crop yield and water productivity.
Farmer-participatory field trials were
conducted in Gorogo and Sepaat
communities, Upper East Region, Ghana, in
the 2020/2021 and 2021/2022 irrigation
seasons to evaluate the yield response of
tomato and onion crops to varied levels of
deficit irrigation using Bhungroo irrigation
technology. The experimental factor was
water application depth at four levels: 65, 85,
and 100% of crop water requirement (CWR)
and farmers’ discretion. Irrigation water
productivity (IWP) was computed as a
function of the yield and water applied.
Seasonal water used in the tomato fields
ranged from 232 to 502 mm, while the onion
trials varied from 358 to 750 mm. The fresh
fruit yield of tomato ranged from 6.0 to 17.5 t
ha−1 in the two seasons, while the dry onion
bulb yields ranged from 15.2 to 25.4 t ha−1.
The IWP ranged from 2.11 to 3.61 kg m−3 for
tomato and from 2.05 to 4.51 kg m−3 for
onion. The lowest values were obtained from
the least water applied, while the highest
values were obtained from the highest. The
deficit irrigation schedules significantly
decreased both yield and IWP compared to
100% CWR in tomato and onion, while the
farmers’ discretion led to over-irrigation in
both study locations. It is recommended that
tomato and onion crops be irrigated to meet
the full crop water requirement in the study
areas.
