Abstract
Cacao production under agroforestry systems (AFS) can increase the incidence of diseases such as Moniliophthora roreri (Cif.) Evans et al., commonly known as Frosty Pod Rot (FPR) of cacao. However, some clones have shown tolerance to this disease, even under AFS conditions. Therefore, this study aims to identify the behavior of different cacao clones planted under full sun and shade conditions with the aiming of identifying clones that combine greater tolerance to the disease with superior yields to 1000 kg ha −1 year −1 under AFS in the Colombian Amazon. The FPR resistance was evaluated in 18 cacao clones under both artificial inoculation and field conditions. Monitoring was conducted for one year in both full sun and shade. Data were analyzed using linear mixed models to determine differences between factors (i.e., clone, ii. condition) and the Disease Productivity Index (DPI). The FEC-2 clone stood out as the most resistant, showing no external or internal symptoms and the lowest pathogen incidence in both production systems (external severity 0.25 ± 0.07, internal severity 0.35 ± 0.06, and incidence of Moniliophthora roreri 0.15 ± 0.02). Other clones, such as ICS-95 and CCN-51, exhibited moderate tolerance, while most clones were classified as susceptible or moderately susceptible. The analysis revealed that shade conditions increased pathogen incidence in most clones, except for FEC-2. Additionally, clones like ICS-95, ICS-39, and FSV-155 reduced their incidence under shade. The Disease and Production Index (DPI) identified FEC-2 as the most promising clone, combining high productivity and tolerance, followed by ICS-95 and CCN-51, which also demonstrated disease tolerance and good yield levels. Clones such as FEAR-5, FSV-41, FLE-3, and ICS-1 were highly susceptible, while EET-8, FSA-12, and FGH-4 were classified as moderately susceptible. These findings highlight the importance of selecting resistant clones like FEC-2 to improve the sustainability and productivity of cacao in Amazonian agroforestry systems, mitigating losses caused by FPR.