A comparative analysis of organic, inorganic manures, and integrated nutrient management in carrot growth and yield in the global south

Abstract Amid global fertilizer supply chain disruptions and the emerging dual-market demand for carrot ( Daucus carota ) taproots and leafy biomass, optimizing nutrient management is now essential for sustainability. This study investigated the comparative efficacy of organic manure (OM), inorganic manure (IM), and integrated nutrient management (INM) on carrot growth and yield to determine the most viable approaches for farmers in the global South. Using a completely randomized design with three replicates over a 12-week experimental period, the Kuroda variety was subjected to four treatments: an unamended control ( C 0 ), poultry manure ( T 1 ), NPK 15:15:15 ( T 2 ), and a combination of poultry manure and NPK for INM ( T 3 ) . Data were analyzed using means. ANOVA was used to test the null hypotheses at the 0.05 significance level. Findings revealed that carrots planted in T 3 (at 34.39 mm) were taller than those planted in soil treated with IM (28.54 mm), OM (32.35 mm), or C (26.39 mm). Also, carrots planted in T 3 had higher leaf biomass (12.23) than those in T 2 (9.10), T 1 (11.37), and C 0 (8.44). Findings further revealed that carrots in T 2 had longer tubers (17.86 mm) and greater weight (59.52 g) than those in T 3 (14.84 mm, 54.15 g), IM (13.35 mm, 42.48 g), and C 0 (11.55 mm, 31.25 g). Indicating that, while INM ( T 3 ) maximized above-ground vegetative parameters, suggesting it could be the optimal strategy for cultivating carrots for the leafy biomass for livestock feed, the OM application ( T 1 ) had a higher optimum harvestable root yield. Although numerically higher values were observed under INM, there was no statistical significance for leaf biomass. There was a statistically significant difference in root tuber performance. Adopting targeted OM and INM practices could provide sustainable, goal-oriented pathways to optimize agricultural production while buffering domestic farming in the global south against global challenges in food production.