Optimizing Okra (Abelmoschus esculentus) Productivity through Integrated Nutrient Management: Effects of NPK Fertilizer and Cow Dung Manure in the Sudan Savanna, Nigeria

Özet

This study evaluated the influence of NPK fertilizer and cow dung manure (CDM) on okra (Abelmoschus esculentus) yield and its components under the Sudan Savanna conditions of Nigeria. A 4 × 4 factorial experiment in a randomized complete block design with four replications was conducted at Teaching and Research farm, Bayero University, Kano. Treatments included four levels each of NPK fertilizer (0, 200, 300, and 400 kg ha^-1) and CDM (0, 2.5, 5.0, and 7.5 t ha^-1). Results indicated that NPK and CDM significantly (P < 0.001) influenced pod yield, with the highest yields obtained at 200 kg ha^-1 NPK and 7.5 t ha^-1 CDM (4367.00 kg ha^-1 in 2019 and 9148.00 kg ha^-1 in 2020), representing a 391% and 384% increase, respectively, over the control (888.00 kg ha^-1 in 2019 and 1889.00 kg ha^-1 in 2020). Pod length increased significantly (P < 0.001) with 100–200 kg ha^-1 NPK in 2019 but was not significantly affected in 2020, suggesting seasonal variability. CDM at 7.5 t ha^-1 produced the highest pod count (18.47 in 2019 and 24.73 in 2020), outperforming lower rates. The findings underscore the benefits of integrated nutrient management, as the combination of NPK and CDM enhanced soil fertility, increased pod number, and improved total yield. These results confirm that organic and inorganic fertilizers complement each other in optimizing okra productivity. Thus, integrated nutrient management using 200 kg ha^-1 NPK and 7.5 t ha^-1 CDM could be adopted by the farmers for sustainable okra production in nutrient-deficient soils of the Sudan Savanna region.