Response of Wheat to Agro-climatic and Soil Morphopedological Factors in the Forest-savanna Transition Zone of the Ivory Coast

Abstract

Aims: To characterize thermal and rainfall trends, identify the main soil types along a topographic sequence and assess the agronomic response of wheat on these soils according to the seasons. Study Design: To analyze rainfall and temperature trends and conduct a field experiment on soils located within a toposequence according to the seasons. Study Location and Duration: The study was conducted in the forest-savanna transition zone in central Ivory Coast. Climate data were collected over 42 years, from January 1981 to December 2022. The agronomic study was carried out from September 2021, to September 2023. Methodology: (i) Collect climate data to highlight climate evolution, (ii) conduct a morphopedological study on a toposequence to identify soil types, (iii) conduct an agronomic study through experiments carried out in microplots during different seasons to identify the moste sutable soil type and the ideal season for wheat cultivation. Results: The study shows a significant increase in average temperature of approximately over 1°C, as well as a decrease and high variability in rainfall, indicating a notable tendency towards drought in this area. Furthermore, morphopedological analysis reveals the presence of a Regolic Ferralsol at the summit, a Plinthic Duric Petrosol on the upper slopes, an Arenic Duric Petrosol on the middle slopes and an Arenic Fluvisol on the lower slopes. Finally, agronomic trials indicate that wheat performs best when its vegetative phase lapes with the dry season and its reproductive phase with the rainy season, with grain yields ranging from 1 t ha⁻¹ to 4.6 t ha⁻¹. Conclusion: The most sutable soils were the Plinthic Petrosol duric and Arenic Fluvisol and whend the best seasons were the great interseason or the great dry season.