TITLE:
Agronomic Potential of First-Order Inland Valleys for Rice Production under Climatic Variability in Pronou, Central C?te d’Ivoire
AUTHORS:
Aikpa Mireille Christelle Pitta, Bolou Emile Bolou-Bi, Zéphirin Sehi, Thierry Philippe Guety, Brahima Kone
KEYWORDS:
Inland Valley Agroecology, Climatic Variability, Empirical Yield Modeling, Nitrogen Management, Resilient Rice Systems, C?te d’Ivoire
JOURNAL NAME:
Journal of Agricultural Chemistry and Environment,
Vol.15 No.3,
July
29,
2026
ABSTRACT: This study was carried out in the first-order inland valleys of Pronou, Gbêkê region, central Côte d’Ivoire. It investigated the agronomic potential of these ecosystems for optimized rice production under conditions of interannual climatic variability. For the first time in this production system, a prospective modeling approach was adopted using the APSIMX R package interface, within which crop yields were simulated via a process-informed empirical model calibrated against published dose-response relationships for improved inland valley rice varieties in West Africa. This integrative framework combined soil physico-chemical, hydrological, and climatic data (2020-2023) with three rice varieties: NERICA-L19, WAB 56-50, and a local ecotype, simulated under six nitrogen application rates (0, 40, 80, 120, 160, 200 kg N/ha) across three topographic positions. Results demonstrated consistent agronomic stability of the studied inland valleys (feasibility indices ≥ 0.80) despite interannual climatic fluctuations. The optimal planting window spanned April to June, with yield potential peaking in May for all tested varieties. Among the tested varieties, NERICA-L19 consistently outperformed WAB 56-50 and the local ecotype, with predicted yields reaching 6860 kg/ha at 200 kg N/ha and a nitrogen use efficiency exceeding that of the local variety by 18%. Nitrogen fertilization exerted significant and dose-dependent effects on grain yield, predominantly during the climatically favorable period (p 2 = 0.87; F = 62.4; p