Determination of Water Productivity in Potatoes under Different Treatments Applied to Desert Soil

Abstract

Two field experiments were conducted during the spring season of 2020 in Karbala Governorate,
located at latitude 32°42’13.8’’ N, and 43°54’36.6’’E and 27 m altitude, to study the effect of surface
drip and sprinkler irrigation systems to determine the efficiency of water productivity for potatoes
and irrigation intervals, using water conservation technology (polymers) and bio-fertilizers in desert
soils. The experiment included a study of three factors: irrigation system (with two graduations,
surface drip irrigation T₁ and sprinkler irrigation T₂, respectively), irrigation interval (with three
graduations, irrigation every 2 days I₁, irrigation every 4 days I2 and irrigation every 6 days I₃), and
addition of soil conditioners (with four graduations, no soil conditioner C, bio-organic fertilizers B,
polymer P, and P + B). The experiment was designed according to the nested design, with three
replications. Potato seeds (Hermosa variety) grade E were planted. Irrigation scheduling was started
according to the experimental parameters after the germination phase was completed and from 14.02
– 26.04.2020. The irrigation interval I₃ is responsible for the highest total water consumption of 593.04
mm·season^-1 and 1385.08 mm·season^-1 for drip and sprinkler irrigation systems. The average total
yield of tubers was 27.07 m³g·ha^-1 and 25.01 m³g·ha^-1, and the irrigation interval I₁ achieved the highest
mean yield of 29.43 m³g·ha^-1  and 27.36 m³g·ha^-1 for the drip and sprinkler irrigation systems,
respectively. The crop water use efficiency reached 14.66 kg·m^-3 and 6.99 kg·m^-3, which is the highest
value at the irrigation interval I1 and by adding P+B to the drip irrigation and sprinkler systems,
respectively.