Enhancing Agronomic Efficiency of Pearl Millet through Integrated Laying Hen Manure and Mineral Fertilization in Burkina Faso’s Sudano-Sahelian Zone

Abstract

Background: The integration of organic and mineral fertilizers is increasingly recognized as a promising approach to enhance nutrient use efficiency (NUE) and improve the sustainability of cropping systems. The application of organic fertilizers, particularly poultry manure, constitutes a relevant strategy for restoring soil fertility. Such amendments simultaneously improve nutrient availability and enhance the soil’s physical, chemical, and biological properties. Aims: The present study evaluated the combined effect of graded rates of laying hen manure (LHM) and mineral fertilizers on millet growth and yield to identify an optimal organo-mineral fertilization strategy adapted to the Sudano-Sahelian conditions of Burkina Faso. Study Design: A field experiment was conducted using a split-plot design with 16 treatments resulting from the combination of two factors, replicated three times. Place and Duration of Study: The experiment was carried out at the experimental station of the Rural Development Institute in Gampela, Burkina Faso during the rainy season of the 2024/2025 cropping year. Methodology: Two factors were tested: (i) eight fertilizer rates combining LHM, NPK, and urea (R0–R7), and (ii) two millet varieties (Nafagnon and Chakti). Growth parameters, yield components, and yields were measured and analyzed. A total of 48 experimental plots (1 plot × 8 fertilizer levels × 2 variety levels × 3 replications) were used for the experiment. The replications were separated by a distance of 2m, and within the replications, the experimental plots were spaced 2m apart. Channels were constructed between the experimental plots to reduce cross-contamination between treatments due to water runoff from one plot to another. Results: Organo-mineral fertilization significantly improved plant height, tiller number, canopy cover, number of flowering tillers, grain yield, and straw yield. In contrast, panicle length and panicle diameter were not significantly affected. The highest grain yields were consistently obtained under organo-mineral treatments. The results showed no significant differences among the different fertilizer doses (R1–R7) for the evaluated parameters, indicating a clear plateau in crop response across the tested fertilization range. This suggests that the nutrient requirements of pearl millet were already sufficiently met at the lowest organo-mineral dose (R1, laying hen manure + NPK), beyond which additional fertilizer inputs did not result in further agronomic improvement. Conclusion: Organo-mineral fertilization is a sustainable strategy to improve millet productivity under Sudano-Sahelian conditions. Considering agronomic efficiency and fertilizer cost, R1 (2 t·ha⁻¹ LHM + 60 kg·ha⁻¹ NPK + 30 kg·ha⁻¹ urea) is recommended as the optimal fertilization strategy for pearl millet production in Burkina Faso.