Intensive agriculture in tropical rainforest regions relies heavily on synthetic fertilizers, which degrade soil health, create environmental issues, and compromise food security. This study aimed to identify sustainable, locally sourced organic amendments as viable alternatives for cultivating fluted pumpkin (Telfairia occidentalis), thereby reducing reliance on environmentally damaging synthetic inputs. The efficacy of conventional inorganic NPK fertilizer, poultry manure (PM), and five preparations derived from the tropical plant Tithonia diversifolia were compared: fresh shoot tea (TdT), blend (TdB), extract (TdE), shoot biochar (Biochar), and ash (Ash), alongside an unamended control. Solid amendments were applied in split doses (10 t ha-1 PM, 3.75 t ha-1 Biochar, 5 t ha-1 Ash), while liquid formulations (500 ml) were applied regularly between 2 and 8 weeks after sowing. Most treatments significantly improved growth metrics, yield components, and the nutritional content of the produce compared to control group. Crucially, the efficacy of the Tithonia blend and tea on nutritional/mineral quality of the fluted pumpkin seeds surpassed those of conventional NPK and poultry manure. Vine length, count, fresh and dry biomass, leaf count and area, pod count, seed weight, photosynthetic pigments, and relative water content were statistically similar across NPK, PM, TdB, and TdT treatments. The overall performance trend was TdB TdT Biochar Ash TdE. The superior performance of green biomass formulations (TdB and TdT) is attributed to rapid nutrient mineralization, which enhances nutrient uptake efficiency comparable to synthetic NPK. These organic amendments, by improving the soil, optimize nutrient allocation dynamics within the plant. T. diversifolia demonstrates significant potential as a sustainable, on-farm organic fertilizer, offering a practical solution for closed-loop farming systems. The TdB and TdT formulations are particularly effective, matching or exceeding NPK and PM in both yield components and nutritional quality of the produce, confirming their viability as sustainable alternatives
Ayodeji Adeyemi Ogunwole (Tue,) studied this question.