Molecular Surveillance, Prevalence, and Distribution of Cacao Infecting Badnavirus Species in Côte d'Ivoire and Ghana.

The cacao swollen shoot disease (CSSD) caused by a complex of badnavirus species presents a major challenge for cacao production in West Africa, especially Ghana and Côte d'Ivoire. In this study, CSSD species detection efficiency, diversity, and geographic distribution patterns in cacao plantations in Ghana and Côte d'Ivoire were investigated through field surveillance, PCR detection assays, sequencing of positive amplicons, and phylogeographic clustering. Cumulatively, the detection efficiency of the tested CSSD primer sets that were targeting the movement protein domain of the virus ranged from 0.15% (CSSD-3 primer) to 66.91% (CSSD-1 primer) on all the symptomatic cacao leaf samples assessed. The identified CSSD species differed phylogenetically and overlapped in distribution, with the cacao swollen shoot Togo B virus (CSSTBV) (n = 588 sequences) being the most prevalent and widely distributed compared to the other CSSD species that were encountered in both countries. Geographically, the cacao swollen shoot CE virus (CSSCEV) species (n = 124 sequences) that was identified was largely restricted to the bordering regions of Ghana and Côte d'Ivoire. These results provide updated knowledge of the geographic distribution of the key CSSD species and their diagnostic efficiency and, thus, provide guidance in identifying locations for structured testing of cacao germplasm and optimal diagnostics for the predominant CSSD species in Ghana and Côte d'Ivoire.

Drivers of cocoa agroforestry adoption by smallholder farmers around the Taï National Park in southwestern Côte d'Ivoire.

The encroachment of agricultural expansion into protected areas has led to severe biodiversity loss. To promote sustainable agriculture practices and reverse the anthropogenic pressure, several initiatives such as the Cocoa and Forests Initiative (CFI) and the National Strategy for Reducing Greenhouse Gas Emissions from Deforestation and Forest Degradation (REDD+), have been undertaken. This study examines the adoption of cocoa agroforestry by smallholder farmers in the vicinity of the Taï National Park (TNP) in Southwestern Côte d'Ivoire. A structured questionnaire was administered to 323 cocoa farmers to understand their practices and perceptions of cocoa agroforestry. Results showed that most farmers (95%) grow unimproved cocoa varieties with an average yield of 376 ± 36 kg ha-1 year-1. The majority of farmers (86%) use agroforestry practices in their farming systems, with pruning techniques being used by 82% and fertilizers applied by 27%. Additionally, 54% of farmers are adopting improved agroforestry practices or planting more trees in their cocoa plantations. Factors influencing cocoa agroforestry adoption include gender, the length of residency, the number of cultivated cash crops and the incidence of black pod attacks. These findings highlight the potential to leverage community knowledge in promoting sustainable agricultural practices and generate positive impacts. These results have important implications for future initiatives aiming to promote sustainable agriculture practices and biodiversity conservation in the region. By capitalizing on the adoption of agroforestry and leveraging socioeconomic factors, it is possible to enhance the conservation of the TNP and promote sustainable cocoa farming practices.

Successful grafting elite cocoa clones (Theobroma cacao L.) as a function of the age of rootstock.

Côte d'Ivoire, the world's largest cocoa producer, faces numerous challenges because the yield of orchards is low due to several factors including the non-use of improved plant materials. This work is part of ICRAF's Vision for Change (V4C) project, which aimed at contributing to the regeneration of cocoa farms by making effective plant materials available to small cocoa producers. It essentially consisted in evaluating the effect of the age of the rootstock on the success of grafting to obtain a satisfactory quantity of improved plants in the nursery. The study was carried out in Adiopodoumé at the National Agronomic Research Center (CNRA). Ten elite cocoa clones from the "Vision for Change" project were used as scions. Top grafting was performed on seedlings of 2, 3- and 4-months used as rootstocks. The experimental design was a randomized complete block design with 3 replications. Data collection was focused on the grafting success rate and morphological parameters. The results showed that the grafting success rate is proportional to the rootstock age. Two months after grafting, the success rate was low. This indicates that grafting should eventually start at 3 months. This period could therefore represent a good stage to successfully graft and replant cocoa seedlings.