Performance Evaluation of a Water-Conserving Drip Irrigation System for Sustainable Vegetable Production under Greenhouse Conditions in Ogbomoso, Nigeria.
1,*Oguntade, R. L., 2Adegbola, A. A., and 3Olaniyan, O. S.
1,2,3,Department of Civil Engineering, Ladoke Akintola University of Technology, Ogbomoso, Nigeria
DOI: 10.36108/laujoces/6202.61.0240
Abstract
Greenhouse farming offers a controlled environment that promotes precision irrigation and sustainable crop production. However, conventional irrigation practices in water-scarce regions such as Ogbomoso, Nigeria, often result in inefficiencies including evaporation, runoff, and over-irrigation. This study was conducted to evaluate the efficiency of a prototype irrigation system developed to conserve water while maintaining optimal vegetable growth. A dome-shaped 8 × 24 m greenhouse integrated with a drip irrigation system was designed and constructed. The crop water requirement (ETc) was determined using the Blamey–Cradle approach, while three deficit irrigation regimes—100%, 80%, and 60% ETc were examined to assess their effects on plant height, leaf number, and leaf diameter. Similarly, fertilizer rates of 0, 25, 50, and 75 kg/ha were applied to evaluate nutrient response under controlled conditions. Results showed that greenhouse temperatures ranged between 24.6°C and 25.6°C, with corresponding ETc values from 4.24 to 5.56 mm/day. Plant growth parameters under 100%, 80%, and 60% ETc averaged 250.86, 210.74, and 165.28 mm in height; 25, 32, and 11 leaves; and 190.41, 165.79, and 145.62 mm in leaf diameter, respectively. For fertilizer application, plant height, number of leaves, and leaf diameter peaked at 286.98 mm, 34, and 213.26 mm, respectively, under 50 kg/ha. Soil parameters including electrical conductivity, pH, organic matter, and temperature improved under moderate irrigation and fertilizer conditions. Regression models revealed R² values of 0.998 and 0.999, confirming strong predictive accuracy. The study concludes that 80% ETc and 25–50 kg/ha fertilizer optimize greenhouse productivity, conserve water, and sustain soil fertility.
Keywords: Greenhouse Farming, Crop Water Requirement, Deficit Irrigation, Fertilizer Rate, Soil Properties
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