Cocoa swollen shoot disease (CSSD) is a major threat to cocoa production. This viral disease has persisted endemically in West African cocoa farms since the 1920s. Its expansion over the past 20 years has led to significant yield losses, with infected trees dying within 3–5 years. The disease has devastated thousands of hectares of cocoa plantations and negatively affected the livelihoods of thousands of farmers.
Despite government efforts to contain the disease, new outbreaks continue to emerge in Ghana, Nigeria, Togo, Sierra Leone and Côte d’Ivoire. The limited understanding of the disease’s spatial dynamics in the field makes planning control strategies and monitoring outbreaks inefficient. Developing a rapid predictive model to monitor the spatial dynamics of disease spread is therefore essential to strengthen CSSD management strategies and better target control interventions.
Tag: cocoa
Policy Change and Expected Policy Impacts: An ACF Analysis of the Roadmap to Deforestation-free Cocoa in Cameroon
Cameroon’s ambition to produce 600,000 metric tons of cocoa by 2025 and double this target by 2030 is often interpreted as a threat to remaining forests because Cameroon cocoa is traditionally established on forest land. Signing the Roadmap to Deforestation-free Cocoa can be considered a major policy milestone in the cocoa sector in Cameroon, and thus provides a case to use the Advocacy Coalition Framework (ACF) to understand actors’ beliefs and links to policy change. The case study is useful because the Roadmap is intended to enhance sustainable cocoa production in the country, but it is entangled by positive and opposing objectives of government, farmers, the private sector, and other stakeholders. Specifically, this chapter uses the ACF lens to identify and map actors in the deforestation-free cocoa policy subsystem and processes, analyze the drivers of policy change, and assess actors’ perceptions, motivations, and beliefs that desired changes can be achieved through the proposed policy instrument.
High variability in spore infectivity and factors influencing native arbuscular mycorrhizal fungi diversity in Côte d’Ivoire cacao rhizospheres
Arbuscular mycorrhizal fungi (AMF) play a central role in enhancing nutrient uptake by plants, increasing resilience to biotic and abiotic stresses, and supporting proper functioning of tropical agroecosystems, such as cacao plantations. However, little is known about diversity and capacity of native strains in rhizospheres, as well as soil factors shaping AMF communities. This study aimed to assess (i) AMF diversity and abundance in cocoa rhizospheres and the relationship with soil chemical properties and climatic variables at seven distinct areas in Côte d’Ivoire, i.e., Adzope, Agnibilekrou, Azaguie, Biankouma, Ble, Bonon and Soubre; (ii) in-situ capacity of strains from these rhizospheres. Soil samples were collected in 66 cocoa plots and AMF spores were extracted and identified based on morphometric criteria. Part of soils was used for trap cultures, while another part was used for determination of chemical properties. Our findings indicate that fungal communities associated with cacao are dominated by families Glomeraceae and Acaulosporaceae. Before establishment of trap cultures, cacao rhizospheres showed highest spore abundance at Ble (103 ± 47 spores/100 g soil) and lowest abundance at Biankouma (47.3 ± 21.6 spores/100 g soil). AMF strains from Agnibilekrou and Biankouma soils showed highest quantitative sporulation capacity, whereas strains from Soubré soils exhibited strongest infective capacity. 18.49% of variance in AMF community is explained by soil chemical variables, whereas 5.32% is explained by climatic variables, with Mn, Zn, Cr, and precipitation as main drivers. This study highlighted that a clear understanding of AMF communities in cocoa rhizospheres is essential to facilitate the design of efficient soil and plant conservation strategies, thus ensuring the sustainability and long-term productivity of cocoa agroecosystems in Côte d’Ivoire.
Refining land-use-specific carbon emission factors for commodity-driven deforestation monitoring in Colombia
Deforestation remains one of the most significant sources of greenhouse gas emissions globally. Tropical regions are particularly critical to climate mitigation due to their high carbon density and ongoing conversion to agricultural uses. While earth observation (EO) has become fundamental for assessing land-use change over time and space, key gaps persist in understanding associated carbon emissions (CE) and their distribution across production systems, information required by diverse international and European policy frameworks targeting greenhouse gas reduction and deforestation. To address this, the study integrates satellite-derived aboveground biomass (AGB) with machine learning-based land-use modeling to quantify commodity-specific CE from deforestation in Colombia. Our key findings reveal that pasture expansion for livestock dominates emissions (>67% in the Amazonas and Orinoquía regions, approximately 25% nationally), while cocoa and coffee, despite smaller cultivation areas, exhibit high emission factors (>25% of subregional totals in the Andes, Pacífico, and Caribe). Smallholder croplands contribute up to 16.7% regionally, and oil palm plays a modest role nationally. These results underscore the importance of targeting both extensive pasture systems and high-emission perennial crops in deforestation-free supply chain policies, while considering the diverse regional land-use dynamics. In conclusion, our framework offers spatially explicit, crop-specific emission estimates that address essential gaps in EO-based CE quantification. It provides clear, actionable baselines for monitoring policies aimed at promoting deforestation-free supply chains, such as the EU Deforestation Regulation (EUDR), across tropical landscapes. Ultimately, this data supports the creation of a comprehensive database of country-specific emission factors, a resource critical for enhancing national carbon inventories, guiding policy decisions related to high-risk deforestation commodities, and ensuring more transparent and traceable zero-deforestation supply chains.
Tree-powered bioeconomies in Africa
Key Facts
- Africa is a leading producer of six tree commodities: cocoa, shea, cashew, gum arabic, baobab and argan oil. It also contributes to the global supply of several other tree commodities of significance, including coffee, wood, oil palm, rubber, avocados, and dates.
- About 11 countries in sub-Saharan Africa can be classified as tree-commodity dependent economies. Seven of them depend on a single tree commodity, while four depend on multiple tree commodities.
- Tree commodities are grown on and occur on more than 100 million hectares of land across the continent.
- Africa captures less than 10% of the global market value for most tree commodities produced.
- Up to 44% of perishable tree fruits, such as mangoes, avocados, oranges and other citrus species, are lost annually across many countries on the continent.
- Forestry contributes more than 10% of the formal gross domestic product (GDP) in about 11 African countries.
- Wood demand in Africa is expected to triple by 2050.
- An estimated 5,400 plant species and 16,000 medicinal applications have been documented in Africa, with the potential to serve as building blocks to supply part of the USD 50 billion-a-year pharmaceutical market on the continent with biopharmaceuticals.
- Africa’s middle class could grow to 40% of the continent’s population by 2060, potentially fuelling demand for high-value tree bioeconomy products and trade through the African Continental Free Trade Area (AfCFTA).
- Only three holistic national bioeconomy policies exist in Africa (South Africa, Namibia and Ethiopia) and one regional bioeconomy strategy (the East African Community). Meanwhile, 13 countries have relevant indirect strategies and policies.
Biological control using essential oil of Ocimum gratissimum and four other biopesticides on Formicococcus njalensis, the most active mealybugs species in the transmission of CSSV (Cocoa swollen shoot virus)
A laboratory investigation was conducted to evaluate the use of Ocimum gratissimum essential oil to control the development of Formicococcus njalensis, the main vector of Cocoa Swollen shoot virus (CSSV) in West Africa. Commercial biopesticides (Squad, Agriphy, Mycotal and Banole), the essential oil of O. gratissimum obtained by hydrodistillation were compared at the concentration of 0, 1000, 2000 and 3000 µl.l-1 respectively. Ten mealybugs were directly sprayed using the different concentrations. The mortality rate of the mealybugs was evaluated by counting the number of mealybugs dead in each Petri dish 24, 48, 72 and 96 h after treatment. The highest toxicity was observed with Squad which killed all the mealybugs at each of the 3 concentrations. The second highest toxicity was observed with O. gratissimum treatment which mortality rate increased with the concentration. Indeed, a mortality rate of 39.27, 50 and 59% was observed at 1000, 2000 and 3000 µl.l-1 respectively. The third highest lethality rate was observed with Agriphy (29.36%) at 1000 µl.l-1 and with Banole (48%) at 2000 µl.l -1. At 2000 µl.l -1, Agriphy and Mycotal lethality rates were 41.4 and 5% respectively. No death was observed in the control treatment. Conclusively, environmental friendly biopesticides such as O. gratissimum and Squad can be used to control Formicococcus njalensis population, and hence limit CSSV prevalence.
Stability of productivity parameters of six cocoa clones [Theobroma cacao (Malvaceae)] during the main production season in Côte d’Ivoire
The strong climatic fluctuation observed during the major cocoa production period with reductions in rainfall and rising temperatures lead to a low graining index. This climatic situation makes cocoa marketing difficult for producers. The stability of quantitative productivity parameters in six cacao clones on farm was analyzed during the main production season. Flowering, average pod weight, number of beans per pod, average bean weight, bean size, and pod index were analyzed. The results obtained showed that the flowering intensity of the clones was high in September (49.07). The average weight of pods decreased from 511.38 g in September to 433.53 g in January. The average weight of a bean and the weight of 100 beans, respectively of 1.3 g and 125.62 g at the beginning of the season dropped in January to 1.13 g and 94.03 g. Clones C8 and C15 showed more stable agronomic characteristics, notably average pod weight, average bean weight, bean size, and pod index during the major production phase. These two promising clones could be used in the rehabilitation phase of degraded cacao plantation, given the stability of their agronomic characteristics.
Preferential expression of somatic embryogenesis in five elite genotypes of Theobroma cacao (L.) associated with explant type and protocols used
This study aims to identify the suitable subculturing time, culture media (protocols) and explants type suitable for somatic embryogenesis expression in five elite genotypes of Theobroma cacao L. Thus, petals and staminodes explants extracted from immature flower buds of genotypes (C1, C8, C9, C14, and C16) are first grown in different media (CIM and CDM) to assess the subculturing time. Then, successive transfers in EDM medium at every 4 weeks intervals until 24 weeks. To assess culture media preference, these genotypes were grown in four different protocols (I, II, III, and IV) for callus induction. They were then successively subcultured (four times at 4 weeks intervals) into EDM. About the subculture time, embryo expression is earlier in C1, C9, C14, and C16 genotypes (2nd and 4th weeks) than C8 genotype (12 and 16th weeks). However, C1, C14, and C16 (with staminodes explants) prefer protocol IV, while their petal explants prefer protocol II. Also, C9 staminodes explants prefer protocol III while the C9 and C8 petals explants prefer protocol I. This study has identified suitable explants and protocols for somatic embryo production in the tested genotypes. Moreover, this work has laid out a new strategy to overcome recalcitrance to the somatic embryogenesis of T. cacao genotypes.
Cocoa (Theobroma cacao) and local fruit species interaction: Case of Beilschmiedia mannii in traditional agroforestry systems in western Côte d’Ivoire
Cocoa (Theobroma cacao) cultivation in Côte d’Ivoire faces many constraints and remains one of the main causes of deforestation. However, cocoa-based agroforestry and the domestication of cocoa companion trees would be an alternative to overcome these constraints. This study was conducted to improve the sustainability of cocoa production through its association with “Bitéi” (Beilschmiedia mannii) in the localities of Duekoué, Guéyo and Buyo in Côte d’Ivoire. The Bitéi x cocoa interaction was analyzed through the dendrometric parameters of the B. mannii trees and the density and potential yield of cocoa in each transect of 10 and 20 m. The results indicate that the dendrometric parameters (height, crown diameter, and DBH) of Bitéi in the three localities did not show significant differences. Bitéi had an average aboveground biomass of 443 t/ha. Analysis of the interaction between Bitéi and cocoa showed that this species would have influenced the aboveground biomass, density, crown diameter and yield potential of the cocoa trees. Based on the results obtained, it is suggested that farmers consider a distance of about 5 m between cocoa and B. mannii when establishing cocoa farms, and to use this species to densify the farms in cocoa-based agroforests.
Assessment of the Effect of Garcinia kola (Clusiaceae) on the Carbon Sequestration Capacity and Productivity of Cocoa (Theobroma cacao L) in Cocoa-Based Agroforestry Systems
Aims: Ivorian cocoa production reaching 2 million ton annually at the expense of the forest reserve, and an annual deforestation rate around 2.78%. The integration of agroforestry into cocoa plantations appears to be a suitable approach to combating deforestation of the remaining forest reserves and restoring the degraded cocoa landscape. The choice of species is the key to the success of this program. Our objective was to evaluate the interaction between Garcinia kola and cocoa in traditional agroforestry systems.