TITLE:
Role of Agro-Climatic Factors in the Epidemiological Dynamics of Cocoa Black Pod Rot in Côte d’Ivoire
AUTHORS:
Josiane Victoria Flean Assande, Théodore Kouakou Kouadio, Eric-Olivier Tienebo, Klotioloma Coulibaly, Adjoa Marie Josephine Kouadia, Akissi Sandrine Yao, Massiata Dagnogo, Kouassi Allou, Kouabenan Abo
KEYWORDS:
Theobroma cacao, Phytophthora megakarya, Black Pod Rot, Rainfall, Epidemiology
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.15 No.12,
December
25,
2025
ABSTRACT: Black pod rot of cocoa pods, caused by Phytophthora spp., accounts for production losses of up to 30% worldwide. The disease typically emerges at the onset of the rainy season, when pods at all stages of development are present on the trees. However, the role of environmental factors in its epidemiology remains poorly documented in Côte d’Ivoire. This study investigated the effects of rainfall, relative humidity, and temperature on the development of black pod rot, intending to identify predictive climatic indicators in five cocoa-growing localities (Duékoué, Yamoussoukro, Divo, Abengourou, and Aboisso) between June 2021 and June 2024. In each locality, four plots were monitored. On each plot, fruit production was recorded every 15 days on 100 trees, while climate data were collected daily. Statistical analyses included Spearman’s correlation to assess non-linear relationships between climatic variables and disease incidence, autocorrelation to detect temporal dependencies, cross-correlation to evaluate interactions among variables, and logistic regression to model the probability of black pod rot occurrence. Results revealed a significant correlation between rainfall and symptom expression, with a lag of less than 15 days. Phytophthora palmivora and P. megakarya were isolated in all localities. These findings provide a basis for developing an early warning system to enhance phytosanitary management of cocoa.