International Journal of Irrigation and Agricultural Development (IJIRAD)

Biochar Rates and Bio-Nematicide Effects on Tomato (Solanum lycopersicum L.) Growth, Yield and Root-Knot Nematodes (Meloidogyne spp.) Suppression in Northern Ghana

2026-09-08T01:18:37+00:00

Root-knot nematodes (Meloidogyne spp.) are among the most destructive pests limiting tomato production, particularly in tropical regions. Two experiments (pot and field trials) were conducted at the University for Development Studies, Nyankpala, Ghana, to evaluate the effects of different biochar amendment rates on the efficacy of a peptide-based bionematicide (Nemanol) in suppressing root-knot nematodes and improving tomato yield. The pot experiment comprised five (5) treatments; 0, 1, 3, and 5% biochar (w/w), applied with or without 5mL of peptide solution. Treatments were arranged in a completely randomized design with four (4) replications. The field experiment evaluated biochar application rates of 0, 2, 4, and 6 t/ha combined with 20 mL of peptide solution per plant, using a randomized complete block design with three (3) replications. In both experiments, treatments significantly (p<0.05) affected most measured growth, yield and nematode infestation indices. Low biochar application rates (1–3% in the pot experiment and
2 t/ha in the field experiment) significantly enhanced plant growth, canopy spread, flowering, and fruit yield compared with the control and higher biochar rates (5% in pots and 6 t/ha in the field). The combined application of 1% biochar and peptide increased plant height by 28.9%, while 2 t/ha biochar combined with peptide reduced root galling severity by 58.3% relative to untreated soil. Biochar amendment also reduced soil pH to a range more favourable for tomato growth. Overall, the combination application of moderate biochar rates and a peptide-based bionematicide effectively suppressed root-knot nematode populations and improved tomato growth and yield. These findings suggest that applying 2 t/ha of rice husk biochar together with 20mL per plant of peptide-based bionematicide can be recommended as an effective management strategy for root-knot nematodes control in tomato production in the study area.

Design, Fabrication and Preliminary Performance Evaluation of a Portable Geared Solar Irrigation Pump for Smallholder Farmers

2026-09-08T01:18:37+00:00

Agricultural productivity in many regions is increasingly challenged by erratic rainfall patterns, climate variability and limited access to affordable energy sources for irrigation. Although solar-powered irrigation systems have emerged as sustainable alternatives to diesel and grid powered pumps, many existing small-scale systems operate under fixed pumping conditions with limited adaptability to varying irrigation requirements. This study presents the design, fabrication and preliminary performance evaluation of a portable Geared Solar Irrigation Pump (G-SIP) developed to provide flexible water delivery for small-scale irrigation applications. The developed system integrates a 150 W photovoltaic module, 40 Ah battery storage unit, a 48 V DC motor and a three-gear transmission mechanism to enable its operation under different pumping conditions. Preliminary test was conducted on the prototype to determine the effects of gear configuration on motor speed, static head and discharge rate. It was revealed that the highest static heads reached were 15.4, 12.0 and 9.5 m with discharge rates of 32, 28 and 21 L min⁻¹, respectively for Gear 1, Gear 2 and Gear 3. It was further observed that the battery required approximately 4.75 hours of sunlight exposure to fully charge the battery. This enabled the pump to operate for up to 10 hours using stored energy. The developed G-SIP combines portability, use of renewable energy, local fabrication capability and adjustable pumping performance in one irrigation unit. These preliminary findings demonstrate the potential of integrating an adjustable geared transmission system with solar energy technology to enhance the adaptability of small-scale irrigation pumps while reducing dependence on conventional energy sources.

Performance Metrics and Effectiveness of Agricultural and Mechanical Engineering Laboratories in Technical Universities in Ghana: Implications for Practical Skills and Industry Readiness

2026-09-08T01:18:37+00:00

Agricultural and mechanical engineering education depends on functional laboratories and workshops that enable students to translate theoretical knowledge into practical competencies. This study assessed how selected performance metrics influence laboratory effectiveness and student outcomes in technical universities in Ghana. A quantitative cross-sectional survey design was employed, involving 275 valid student responses from five (5) technical universities in Tamale, Bolgatanga, Wa, Ho and Sunyani. Data were analysed using partial least squares structural equation modelling (PLS-SEM). The model examined infrastructure adequacy, safety compliance, competency-based training, industry alignment and operational efficiency as performance metrics; laboratory effectiveness as a mediating construct; and skill acquisition, industry readiness and employability as student outcomes. Operational efficiency was the strongest predictor of laboratory effectiveness (β = 0.599, p < 0.001), followed by safety compliance (β = 0.227, p<0.001). Infrastructure adequacy, competency-based training and industry alignment were not significant predictors. For aggregate student outcomes, infrastructure adequacy (β = 0.162), safety compliance (β = 0.164), industry alignment (β = 0.254) and operational efficiency (β = 0.468) were significant, whereas competency-based training was not. Laboratory effectiveness strongly predicted skill acquisition (β = 0.913), industry readiness (β = 0.912) and employability (β = 0.777), all at p<0.001. Mediation effects were significant for skill acquisition (β = 0.821), industry readiness (β = 0.819) and employability (β = 0.699). The findings indicate that practical training effectiveness depends more on efficient operation, maintenance, safety and industry relevance than resource availability alone. Strengthening these areas can improve engineering graduates’ technical competencies, industry readiness and employability.

Growth and Proximate Composition of Amaranth as Influenced by Biochar Amendment Rates and Endophytes Application Under Field Conditions

2026-09-08T01:18:37+00:00

Soil fertility management remains a major challenge in vegetable crop production, particularly in container gardening systems. Biochar soil amendment and the application of exogenous endophytes are two technologies with potential to improve plant performance under container production conditions. This pot experiment investigated the combined effects of rice husk biochar (RHB) amendment and foliar application of endophytes on soil fertility, nutrient availability, biomass production, and nutritional composition of Amaranthus hybridus under field conditions at the University for Development Studies, Ghana. The five treatments used were 100% topsoil (control). foliar application of mixed bacterial and fungal endophytes products, and three topsoil-to-RHB ratios (90:10, 75:25, and 50:50, w/w), each combined with foliar application of the endophyte products. The completely randomized design with three replications was used. The application of biochar at different rates in combination with endophytes significantly (p<0.05) improved soil chemical properties and moisture retention. The moderate biochar rate (25% RHB + endophytes) particularly enhanced nutrient availability, with soil N, P, and K concentrations of 0.269%, 6.31 mg/kg, and 4.41 cmol/kg, respectively, as well as soil moisture content. This treatment also promoted vegetative growth, producing the tallest plants (42 cm), the highest biomass yield (197.7 g), and the greatest protein content (11.44%) in the edible leaves. Endophyte application alone also improved plant growth parameters relative to the control. Nutritional analysis further showed that the combined application of biochar and endophytes increased the dry matter, ash, fibre, and protein contents of the leaves. Overall, the application of 25% RHB with 75% topsoil, combined with foliar endophyte application, improved soil fertility, plant growth, biomass production, and nutritional quality of Amaranthus. The moderate biochar–endophyte treatment could therefore be considered for container-based vegetable production; however, biochar application should be carefully managed rather than routinely applied because of its potentially long-lasting effects on soil properties.