Seasonal influence of shade on the disease incidence of Moniliophthora perniciosa in cocoa: Longitudinal study

Ecuador’s Amazon region is a global hotspot for fine-flavor cacao production, yet yields are frequently threatened by witches’ broom disease ( Moniliophthora perniciosa ) which can reduce harvests by more than 30%. This longitudinal comparative study evaluates the seasonal influence of shade on the disease incidence of cocoa witches’ broom ( M. perniciosa ) in Ecuadorian Amazon region. Fifteen fine-flavor cacao farms were selected, distributed across the provinces of Sucumbíos and Orellana, establishing experimental plots with controlled shade management and control plots with traditional management. Over 60 months, shade variables were measured, and the incidence of the disease known as “witch’s broom” was assessed. Results indicate that experimental plots exhibited a higher percentage of shade (43.7%) compared to control plots (35.33%) during the summer. This increase in shade was correlated with greater disease incidence of M. perniciosa , evidenced by an increase in the number of terminal and floral broom formations. ARIMA models applied revealed that seasonal shade management significantly influences disease incidence, with projections showing stable temporal conditions in experimental plots compared to the seasonal variability in control plots. The research concludes that proper shade management can reduce the incidence of M. perniciosa , providing a more stable and predictable microclimate. These findings underscore the importance of integrating phytosanitary management strategies and sustainable agroforestry practices to mitigate the effects of climate change and improve the resilience of cacao production systems.