Abstract:
In northern Togo where rainfed maize is one of the major crops grown, agriculture is subject to frequent yield
losses due to erratic rainfall. To ensure food availability and improve agricultural productivity, it is necessary to
produce maize during the dry season under irrigation. A sound application of full and deficit irrigation requires
a thorough understanding of the crop parameters and yield response to water. Thus, this study investigated
the effect of full and deficit irrigation on maize plant above-ground biomass, leaf area index, canopy cover,
plant height, and grain yield. A field experiment was carried out from December 2017 to April 2018 in northern
Togo at the agronomic research institute. Full irrigation (FI), 80% FI, and 60% FI treatments were applied.
The results showed that in the late-season stage, the differences in biomass between FI and 60% FI were
significant (p < 0.05). On average, FI had the greatest grain yield (2 200.4 kg/ha), while the lowest grain yield
was recorded under 60% FI (1 068.3 kg/ha). The grain yield differences between FI and 60% FI were significant.
Nevertheless, the grain yield differences between FI and 80% FI were not significant (p > 0.05). 80% FI had
water use efficiency (WUE) (0.22 kg/m3) similar to that of FI (0.21 kg/m3), on average. The results of this study
illustrate that deficit irrigation must be carefully managed since slight differences in the application volumes
affect the biomass and yield of maize significantly. Under a moderate level of deficit irrigation (vegetative and
reproductive growth stages) the biomass and the grain yield of maize are reduced. However, a moderate level
of deficit irrigation during the vegetative growth stage could result in similar values of WUE to that of FI.
