Development and Assessment of Organic Fertilizer Applications on Tomato Yield and Quality

Thesis Abstract

The increasing global demand for sustainable agriculture and the widespread concern over the environmental and health impacts of synthetic fertilizers have driven the exploration of organic alternatives to enhance crop productivity and quality. Tomatoes, as a major horticultural commodity, are often cultivated with chemical inputs; however, the adverse effects of such inputs necessitate the development of environmentally friendly fertilization strategies. This study aims to develop and assess the efficacy of locally formulated organic fertilizers on tomato yield and quality parameters, with specific objectives to determine the optimal application rates, evaluate effects on physicochemical and sensory attributes, and analyze economic viability. A randomized complete block design (RCBD) was employed, involving six treatments comprising different organic fertilizer formulations and a control with chemical fertilizer. The population comprised 240 tomato plants cultivated across four experimental plots, each subdivided into six blocks, resulting in 40 plants per treatment. The organic fertilizers were developed using locally sourced raw materials such as composted farm residues, vermicompost, bird droppings, and leguminous seed meals, characterized through proximate analysis prior to application. Data collection instruments included standardized measuring tools for yield assessment, laboratory analyses for fruit nutrient content, and sensory evaluation panels for quality attributes. Data were analyzed using analysis of variance (ANOVA) to determine statistically significant differences among treatments at a 5% significance level, supplemented with Tukey’s post hoc test. Regression analysis was conducted to explore relationships between fertilizer application rates and crop responses, while economic analysis utilized cost-benefit ratios to evaluate profitability. The anticipated findings suggest that specific combinations or application rates of organic fertilizers will significantly enhance tomato yield and improve fruit quality, including increased nutrient density, better flavor profiles, and longer shelf life, compared to conventional chemical fertilization. It is expected that organic treatments will demonstrate viable economic returns, making them attractive options for smallholder farmers seeking sustainable intensification. The results aim to contribute novel insights into locally adaptable organic fertilizer formulations, with the potential to reduce reliance on synthetic chemicals and promote environmentally sustainable tomato production systems. This research will expand existing knowledge on organic nutrient management in tomato cultivation, offering a scientifically validated framework for formulation, application, and evaluation. By integrating farmers’ practices with scientific innovation, the study seeks to close gaps in the literature regarding the biological efficacy and economic feasibility of organic fertilizers in tropical crop systems. The findings are expected to inform policy recommendations on organic farming standards and input promotion, ultimately contributing to improved food security and environmental health. In conclusion, the study advocates for the adoption of tailored organic fertilization strategies, emphasizing their positive agronomic, nutritional, and economic impacts. It recommends further research to optimize formulations for other horticultural crops and diverse agro-ecological zones, alongside extension efforts to encourage farmer uptake. Overall, the study underscores the importance of developing context-specific organic fertilization practices as a sustainable pathway for enhancing tomato productivity and quality in an environmentally conscious manner.