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With the adverse effects of climate change becoming more prominent, more effective strategies for reducing the increase in atmospheric CO2 levels are required for mitigating further climate change. Increasing use of renewable energy by farmers motivated to practice agroforestry is one natural solution for reducing those climate change impacts. Unfortunately, climate change mitigation through agroforestry has been inhibited by a lack of scientific validation. In this paper, we ascertain factors that motivate African cocoa farmers to use agroforestry practices for enhancing food production as well as for mitigating climate change. We analyzed data collected from 120 farmers from the Oyo state of Nigeria through descriptive and regression analysis statistical tools. We found that access to information (β = 0.23, t = 2.18) and extension service (β = 0.23, t = 2.27) was associated with greater willingness of farmers to participate in agroforestry whereas negative attitudes (β = −0.29, t = −3.21) were associated with a lower involvement of cocoa farmers in agroforestry practices. We conclude that effective climate change mitigation programs need to do more to motivate farmers to adopt agroforestry practices by increasing their understanding of the benefits to be derived from carbon markets and by providing them with the necessary tools for employing these practices for climate change mitigation and more sustainable food production. [ABSTRACT FROM AUTHOR]

Since 2000, many African countries have adopted land tenure reforms that aim at comprehensive land registration (or certification) and titling. Much work in political science and in the advocacy literature identifies recipients of land certificates or titles as 'programme beneficiaries', and political scientists have modelled titling programmes as a form of distributive politics. In practice, however, rural land registration programmes are often divisive and difficult to implement. This paper tackles the apparent puzzle of friction around rural land certification. We study Côte d'Ivoire's rocky history of land certification from 2004 to 2017 to identify political economy variables that may give rise to heterogeneous and even conflicting preferences around certification. Regional inequalities, social inequalities, and regional variation in pre-existing land tenure institutions are factors that help account for friction or even resistance around land titling, and thus the difficult politics that may arise around land tenure reform. Land certification is not a public good or a private good for everyone. [ABSTRACT FROM AUTHOR]

Preference for functional and nutritious food capable of meeting consumers' demand and health is on the increase. The present preliminary study seeks to assess physico-chemical and nutraceutical diversity in the cocoa bean powder of 77 genotypes present in four Nigerian cocoa field banks. Twenty ripe pods/genotypes in each of the four active breeding field banks at the Cocoa Research Institute of Nigeria (CRIN), Ibadan, Nigeria were utilized. Composite beans from the 20 pods of each genotype were singly fermented, sun-dried and milled. Duplicate samples of the powder of each genotype were analysed for physico-chemical and nutraceutical components. Twenty-one polymorphic variables distinguished the 77 cocoa genotypes. Grouping by dendogram identified four clusters, three differently and uniquely captured 100% of the genotype membership in the local clone, international clone and the regional varieties field bank but 86% of the genotypes in the hybrid trial field bank were grouped in cluster I. Prominent traits with highest values in each clusters were: protein, p H, Ca, K and Fe (Cluster I), Zn and Mg (Cluster II), crude fat and P (Cluster III) and crude fibre, ash, theobromine, flavonoids and caffeine (Cluster IV). Exploitable diversity for nutritional quality improvement is present in the active breeding and working collections of Nigerian cocoa field banks. [ABSTRACT FROM AUTHOR]

In Indonesia, management practices that reduce soil fertility could be limiting cocoa (Theobroma cacao L.) production. To address this, we investigated the effects of fertilizers and organic amendments comprising different combinations of NPK + urea, dolomite, and manure-based compost on soil properties and cocoa productivity. We extended an existing field experiment in South Sulawesi, Indonesia, to assess these treatments' effects on cocoa trees from the age of 2.9 years to 7.4 years. The treatments were first applied 5 months after planting and subsequently twice a year. Soil analyses were performed before planting, after 3 years, and finally after 7 years. Productivity was assessed yearly between the age of 3.5 and 7.4 years. The highest yields were obtained from the plots receiving compost, although the yield benefits diminished over time. Inorganic fertilizer alone doubled the yield compared to the control, while the yields with compost and compost + fertilizer were three times that of the control. With dolomite alone, the yield cumulated over 4 years was 41% higher than the control. The positive effect of compost on cocoa yields can potentially be attributed to (1) physical changes increasing soil water availability, (2) the chemical improvement of nutrient availability, and (3) biologically, by promoting the activity of beneficial organisms. The application of dolomite increased soil pH, Ca, and Mg contents. Soil organic carbon greatly declined in the composted treatments, even though 10 kg of compost was applied per tree per year, probably because of the low C:N ratio of the compost. Future studies should assess different fertilizer formulations and combinations with organic inputs and explore the mechanisms by which compost promotes cocoa productivity. [ABSTRACT FROM AUTHOR]

Summary: Studies on the effect of nanofertilizers (NF) in physiological performance of plants is scarce, especially that related to substances encapsulated into silicon dioxide (SiO2) nanoparticles in cocoa plants. The effect of foliar application of SiO2-NF on nutrient contents, gas exchange, photochemical activity, photosynthetic pigments, total soluble protein (TSP), photosynthetic nitrogen use efficiency (PNUE), and growth in seedlings of two cocoa clones (OC-61 and BR-05) in a greenhouse was assessed. Spraying with SiO2-NF increased net photosynthetic rate (A) by 16 and 60% and electron transport rate (J) by 52 and 162% in clones OC-61 and BR-05, respectively, without changes in photosynthetic pigment concentration in either clone. The SiO2-NF caused a decrease of 37 and 22% in stomatal conductance in OC-61 and BR-05, respectively; a similar trend was observed in transpiration rate, causing an increase of 42 and 100% in water use efficiency in OC-61 and BR-05, respectively. In both clones, diameter of graft increased on average 28% with SiO2-NF. Higher photosynthetic capacity was related to an increase in leaf N, P, and TSP. A significant reduction in PNUE (A/N ratio) was found in OC-61, whereas in BR-05 PNUE increased after spraying with SiO2-NF. Overall, spraying with SiO2-NF had a positive effect on photosynthetic processes in both cocoa clones, associated with an increase in nutrients content, which translated into improved growth. A differential physiological response to spraying with SiO2-NF between clones was also found, with BR-05 being the clone with a better physiological response during the establishment and development stages. [ABSTRACT FROM AUTHOR]

Wages – the monetary payments that workers receive from employers in exchange for their labour – are widely overlooked in academic and policy debates about human rights and business in global supply chains. They shouldn't be. Just as living wages can insulate workers from human rights abuse and labour exploitation, wages that hover around or below the poverty line, compounded by illegal practices like wage theft and delayed payment, leave workers vulnerable to severe labour exploitation and human rights abuse. This article draws on data from a study of global tea and cocoa supply chains to explore the impact of wages on one of the most severe human rights abuses experienced in global supply chains, forced labour. Demonstrating that low-wage workers experience high vulnerability to forced labour in global supply chains, it argues that the role of wages in shaping or protecting workers from exploitation needs to be taken far more seriously by scholars and policymakers. When wages are ignored, so too is a crucial tool to protect human rights and heighten business accountability in global supply chains. [ABSTRACT FROM AUTHOR]

Summary: Cocoa (Theobroma cacao) farmers in Sulawesi, Indonesia typically use subsidised, ammonium-based rice fertilisers that in combination with poor agricultural practices have resulted in soil acidification, loss of organic matter, aluminium toxicity and lower soil fertility. As a result, these soils are only marginally appropriate for replanting cocoa to boost production. A field experiment was performed to test alternative soil amendments for successful replanting of cocoa on these deficient soils. In a trial with a randomised block design, 6-month old seedlings, top-grafted with the local MCC02 clone, were planted under light Gliricidia sepium shade and after 3 months treated quarterly with two options of mineral fertilisers: either a customised fertiliser, consisting of Nitrabor (a combination of calcium nitrate and boron), dolomite, rock phosphate and KCl or a NPK/urea mix used by farmers, each supplied with or without 'micronutrient' rock salt, organic fertiliser and beneficial microorganisms or their culture medium, a mixture of chitin and amino acids (a total of 20 treatments). Over a 4-year period, the marginal mean rates of stem diameter increment and flowering score were higher in customised fertiliser than NPK/urea treatments. The average growth rate was highest in the first year and was increased by supplying organic fertiliser. A significant correlation (r = 0.22, p < 0.05) occurred between growth and available P, but concentrations of available P were higher in the NPK/urea plots, which also had lower mean growth rates. Combined supply of organic fertiliser and microbes increased available P, as well as growth rates, in both the customised and NPK/urea treatments. In contrast, NPK/urea-treated plots without these amendments demonstrated very low growth rates. The customised formulation was more effective with or without added organic fertiliser or inoculated microbes. Micronutrient supply stimulated flowering. Growth rates in trees supplied with NPK/urea were also promoted by micronutrients. Leaf flush production occurred in regular cycles and was unaffected by the nutrient amendments. After 3 years, the customised and organic fertiliser application increased soil pH and exchangeable Ca and Mg concentrations, although they remained below recommended levels for cocoa production. These treatments had little impact on soil C content (about 1.3%) which was also deficient. Exchangeable Al and total Zn concentrations were higher in soils amended with NPK/urea. The results of the trial provide evidence that utilisation of organic fertiliser in combination with customised nitrate-based formulations improves cocoa establishment, growth and soil properties and should be recommended as a replacement for the NPK/urea fertilisers traditionally used by farmers. [ABSTRACT FROM AUTHOR]

In order to assess the response of cocoa trees to drought, changes in water status, gas exchange, leaf carbon isotopic ratio (δ13C), photochemical activity, and leaf N and chlorophyll content during the rainy and dry season were measured in 31 Venezuelan cocoa clones (17 Trinitarios, 6 Criollos, and 8 Modern Criollos) grown in a common garden. Drought caused a 40% decrease in water potential (ψ) in all but the Modern Criollos, and a reduction in net photosynthetic rate (A) and stomatal conductance (gs) without an increase in instantaneous water use efficiency (WUE) in 93% of clones, and an increase in δ13C (long-term WUE) in 74% of clones; these responses suggest differences in tolerance to drought among clones. A positive correlation between A and both gs and leaf N content was found for all genotypes. Leaf N content, chlorophyll content, and photochemical activity were reduced during drought, suggesting that metabolism was also inhibited. The best performance during drought was shown by Modern Criollos with the highest WUE, while five Trinitario clones seemed to be less sensitive to drought, since neither chlorophyll, N, total soluble protein concentration, nor gs changed with drought, indicating that those Trinitario clones, with lower A, have a conservative water use. Modern Criollos showed no reductions in either ψ or gs; A remained unchanged, as did WUE, which was the highest, suggesting that these clones would be more successful in environments with low water availability. Our results indicate large variation in physiological response to drought over a range of parameters, suggesting possible differences in tolerance among clones. [ABSTRACT FROM AUTHOR]

Dark chocolate is claimed to have effects on gastrointestinal function and to improve well-being. This randomised controlled study tested the hypothesis that cocoa slows gastric emptying and intestinal transit. Functional brain imaging identified central effects of cocoa on cortical activity. Healthy volunteers (HV) ingested 100 g dark (72 % cocoa) or white (0 % cocoa) chocolate for 5 d, in randomised order. Participants recorded abdominal symptoms and stool consistency by the Bristol Stool Score (BSS). Gastric emptying (GE) and intestinal and colonic transit time were assessed by scintigraphy and marker studies, respectively. Combined positron emission tomography–computed tomography (PET–CT) imaging assessed regional brain activity. A total of sixteen HV (seven females and nine males) completed the studies (mean age 34 (21–58) years, BMI 22·8 (18·5–26·0) kg/m2). Dark chocolate had no effect on upper gastrointestinal function (GE half-time 82 (75–120) v. 83 (60–120) min; P =0·937); however, stool consistency was increased (BSS 3 (3–5) v. 4 (4–6); P =0·011) and there was a trend to slower colonic transit (17 (13–26) v. 21 (15–47) h; P =0·075). PET–CT imaging showed increased [18F]fluorodeoxyglucose (FDG) in the visual cortex, with increased FDG uptake also in somatosensory, motor and pre-frontal cortices (P <0·001). In conclusion, dark chocolate with a high cocoa content has effects on colonic and cerebral function in HV. Future research will assess its effects in patients with functional gastrointestinal diseases with disturbed bowel function and psychological complaints. [ABSTRACT FROM AUTHOR]

Summary: Despite the plethora of discourse about how sustainable development should be pursued, the production of agricultural commodities is held responsible for driving c. 80% of global deforestation. Partially as a response, the private sector has made commitments to eliminate deforestation, but it is not yet clear what factors these commitments should take into account to effectively halt deforestation while also contributing to broader sustainable development. In the context of private sector commitments to zero-deforestation, this study characterizes the perceptions of different types of stakeholders along the cocoa and chocolate supply chain in order to determine the main challenges and solutions to encourage sustainable production. The main purpose is to understand the key factors that could facilitate a transition to a more sustainable supply while harmonizing the multiple actors' interests. A qualitative thematic analysis of perceptions was conducted based on responses from 59 interviews with different stakeholders along the cocoa and chocolate supply chain in six key producing and consuming countries. Thematic analysis of the responses revealed six main themes: (1) make better use of policies, regulations and markets to help promote sustainability; (2) improve information and data (e.g., impacts of climate change on cocoa) to inform sound interventions; (3) focus on the landscape rather than the farm-level alone and improve integration of supply chain actors; (4) promote better coordination between stakeholders and initiatives (e.g., development assistance projects and corporate sustainability efforts); (5) focus on interdependent relationships between social, environmental and economic dimensions to achieve sustainable development; and (6) engage with the private sector. The study shows the importance of identifying different stakeholder priorities in order to design solutions that accommodate multiple interests. It also emphasizes the need to improve coordination and communication between stakeholders and instruments in order to address the three different dimensions of sustainability in a synergistic manner, considering the interactions from production of raw material to end consumer. [ABSTRACT FROM AUTHOR]

Over the last two decades, consumption, consumerism, and the idea of consumer agency have attracted a great deal attention from scholars across a number of disciplines. Among historians, the late nineteenth and early twentieth centuries have been identified as a crucial period for consumption, one in which consumers emerged as an influential group of political, economic, and social agents. Historians of the English-speaking world have advanced bold claims about the prominence and impact of consumers during this period. Consumer movements were conspicuously absent in two major scandals of the early twentieth century, however. This article uses these commodity-centered cases—of rubber in the Congo Free State, and cocoa in the Portuguese colonies of São Tomé and Príncipe—to question the salience of “consumerism” in turn-of-the-century political thought. By tracing the career of British journalist and humanitarian activist E. D. Morel through the “red rubber” and “slave cocoa” scandals, the article demonstrates that consumers were only one of many influences along the commodity chain of production and consumption. [ABSTRACT FROM PUBLISHER]

Studies the origins of the Ghana cocoa marketing board during the period between 1939 and 1946. Factors that contributed to the shift to state-controlled cocoa marketing; Operation of wartime cocoa controls; Relationship between trade-induced social conflict and state involvement.

Cocoa-based small-scale agriculture is the most important source of income for most farming families in the region of Alto Beni in the sub-humid foothills of the Andes. Cocoa is grown in cultivation systems of varying ecological complexity. The plantations are highly susceptible to climate change impacts. Local cocoa producers mention heat waves, droughts, floods and plant diseases as the main impacts affecting plants and working conditions, and they associate these impacts with global climate change. From a sustainable regional development point of view, cocoa farms need to become more resilient in order to cope with the climate change related effects that are putting cocoa-based livelihoods at risk. This study assesses agroecosystem resilience under three different cocoa cultivation systems (successional agroforestry, simple agroforestry and common practice monocultures). In a first step, farmers’ perceptions of climate change impacts were assessed and eight indicators of agroecological resilience were derived in a transdisciplinary process (focus groups and workshop) based on farmers’ and scientists’ knowledge. These indicators (soil organic matter, depth of Ah horizon, soil bulk density, tree species diversity, crop varieties diversity, ant species diversity, cocoa yields and infestation of cocoa trees with Moniliophthora perniciosa) were then surveyed on 15 cocoa farms and compared for the three different cultivation systems. Parts of the socio-economic aspects of resilience were covered by evaluating the role of cocoa cooperatives and organic certification in transitioning to more resilient cocoa farms (interviews with 15 cocoa farmers combined with five expert interviews). Agroecosystem resilience was higher under the two agroforestry systems than under common practice monoculture, especially under successional agroforestry. Both agroforestry systems achieved higher cocoa yields than common practice monoculture due to agroforestry farmers’ enhanced knowledge regarding cocoa cultivation. Knowledge sharing was promoted by local organizations facilitating organic certification. These organizations were thus found to enhance the social process of farmers’ integration into cooperatives and their reorientation toward organic principles and diversified agroforestry. [ABSTRACT FROM PUBLISHER]

In this issue we introduce a new, occasional feature in Ancient Mesoamerica: longer, sustained, detailed papers that elaborate the finer points of controversial culture-historical issues or theoretical debates in Mesoamerican studies. Each of these longer pieces will be followed in a future issue by invited commentaries. This first paper involves a debate that has been brewing for some time: the origins of the words for cacao (Theobroma cacaoand congeners [McNeil 2006b:341]) and chocolate and the culture-historical implications. Few things of ancient Mesoamerica have whetted both the intellectual and the culinary appetite like cacao and and its derivative, chocolate. Cacao and chocolate, in fact, have represented many things in Mesoamerica and all over the world: food, beverage, commodity, money?and words that evoke lively scholarly debate. [ABSTRACT FROM AUTHOR]

This article investigates the powerful normative role of plantation-oriented agricultural practices in what was arguably the premier indigenous crop revolution of the colonial era: the West African cocoa boom. It traces the links between the extraordinary growth of cocoa production in the region – above all in the Gold Coast – and the longer experience of cocoa estates in other parts of the world, in particular the Caribbean, which served as a key reference point for the expanding global cocoa frontier in the late nineteenth and early twentieth centuries. In spite of the manifest competitive success of African farmers’ extensive agricultural practices during this period, most outside observers retained a strong partiality towards intensive production techniques under centralized European management. This article emphasizes the role played by the transcontinental exchange of ideas in sustaining the cultural authority of such cultivation techniques long after their commercial viability came into question. [ABSTRACT FROM PUBLISHER]

Data from three cocoa (Theobroma cacao) clonal selection trials are used to investigate the genetic and environmental components of variation in yield and the percentage of total pods affected by black pod disease (Phytophtora pod rot). Simulations based on these estimated components of variation are then used to discuss the best choice in future of numbers of clones, replicates and years of harvest to maximise selection advances in the traits measured. The three main conclusions are the need to increase the number of clones at the expense of the number of replicates of each clone, the diminishing returns from additional years of harvesting and the importance of widening the genetic base of the clones chosen to be tested. [ABSTRACT FROM AUTHOR]

Theobroma cacao L., or cacao, is the source of cocoa products used in the making of chocolate. These tropical trees are conserved in living genebanks. The International Cocoa Genebank, Trinidad is one of the largest ex situ collections in the public domain. Mislabelling is a critical problem and the correction of this problem is vital to improve the accuracy and efficiency of genebank management. Using microsatellite DNA markers, we assessed the level of mislabelling in a group of Refractario cacao that originated from Ecuador and determined their population memberships through Bayesian clustering analysis. The microsatellite data revealed a synonymous rate of 7.5% and an error rate of 39.4% in this germplasm subset. The analysis of the population structure grouped the Refractario accessions into four subclusters, indicating intra-population heterogeneity in this germplasm group. Based on the results, we recommend that when the assignment test is used for cacao genotype identification, it should (a) use duplicated samples as internal checks, (b) choose suitable reference accessions, including a known homogeneous group and (c) employ subclustering checks to obtain reliable results. The information framework generated is discussed in relation to the management of the collection, population enhancement and future research of the collection. [ABSTRACT FROM PUBLISHER]

The results of research into the water relations of cocoa are reviewed in the context of drought mitigation and irrigation need. Background information on the centres of production of the cocoa tree, and the role of water in crop development and growth processes, is followed by reviews of the effects of water stress on stomatal conductance, leaf water status and gas exchange, together with drought tolerance, crop water use and water productivity. Leaf and shoot growth occur in a series of flushes, which are synchronized by the start of the rains following a dry season (or an increase in temperature), alternating with periods of ‘dormancy’. Flowering is inhibited by water stress but synchronous flowering occurs soon after the dry season ends. Roots too grow in a rhythmic pattern similar to that of leaf flushes. Roots can reach depths of 1.5–2.0 m, but with a mass of roots in the top 0.2–0.4 m, and spread laterally >5 m from the stem. Stomata open in low light intensities and remain fully open in full sunlight in well-watered plants. Partial stomatal closure begins at a leaf water potential of about −1.5 MPa. Stomatal conductance is sensitive to dry air, declining as the saturation deficit increases from about 1.0 up to 3.5 kPa. Net photosynthesis and transpiration both consequently decline over a similar range of values. Little has been published on the actual water use of cocoa in the field. Measured ETc values equate to <2 mm d−1 only, whereas computed ETc rates of 3–6 mm d−1 in the rains and <2 mm d−1 in the dry season have also been reported. Despite its sensitivity to water stress, there is too a paucity of reliable, field-based published data of practical value on the yield responses of cocoa to drought or to irrigation. With the threat of climate change leading to less, or more erratic, rainfall in the tropics, uncertainty in yield forecasting as a result of water stress will increase. Social, technical and economic issues influencing the research agenda are discussed. [ABSTRACT FROM PUBLISHER]

Cocoa, a product consumed since 600 BC, is now a subject of increasing interest because of its antioxidant properties, which are mainly attributed to the content of flavonoids such as ( − )-epicatechin, catechin and procyanidins. Moreover, recent findings suggest a regulatory effect of cocoa on the immune cells implicated in innate and acquired immunity. Cocoa exerts regulatory activity on the secretion of inflammatory mediators from macrophages and other leucocytes in vitro. In addition, emerging data from in vivo studies support an immunomodulating effect. Long-term cocoa intake in rats affects both intestinal and systemic immune function. Studies in this line suggest that high-dose cocoa intake in young rats favours the T helper 1 (Th1) response and increases intestinal γδ T lymphocyte count, whereas the antibody-secreting response decreases. The mechanisms involved in this activity are uncertain; nonetheless, because redox-sensitive pathways control immune cell function, the action of cocoa flavonoids on modulating cell signalling and gene expression deserves investigation. [ABSTRACT FROM PUBLISHER]

For 50 years, ‘hybrid vigour’ in crosses involving genotypes collected from the centre of diversity of the crop in the Peruvian Amazon has been the guiding principle of cocoa breeding. In the work described here, six Amazonian genotypes and one Trinitario clone were used to produce four bi-parental crosses. Twenty-two plants of each cross were propagated from plagiotropic buds as ‘cloned seedlings’ and evaluated for growth, yield and yield efficiency (the ratio of yield to continuing vegetative growth) in replicated trials in comparison with the parental clones and the reproduced seedling family. The reproduced seedling families grew faster than and outyielded all the clones in all four crosses, although they showed no gain in yield efficiency. The vigour and yield of the ‘cloned seedlings’ of the three inter-Amazon crosses exceeded mid-parent value (MPV), but not the single Trinitario cross. The pattern of departures from MPVs was inconsistent with current understanding of the genetic distance between the parents. The superiority of the seedlings over the ‘cloned seedlings’ is interpreted as an epigenetic effect. The results suggest that simple recurrent selection is an appropriate breeding strategy in cocoa, with different optimum planting densities for the seedling and clonal phases. It is concluded that if the concept of very large ‘hybrid vigour’ did not already exist in cocoa, it would not be adopted on the evidence of this work, the first in which clones were compared to their progeny grown as clones. [ABSTRACT FROM PUBLISHER]

It has been over 10 years since the first mention in a medical journal about cocoa and chocolate as potential sources of antioxidants for health. During this time, cocoa has been found to improve antioxidant status, reduce inflammation and correlate with reduced heart disease risk; with these results, and its popularity, it has received wide coverage in the press. However, after 10 years of research, what is known about the potential health benefits of cocoa and what are the important next steps in understanding this decadent source of antioxidants? [ABSTRACT FROM PUBLISHER]

Broad sense heritabilities were estimated in three long-term cocoa clone trials in Ghana, with 20, 18 and 15 entries. They were 0.15, 0.05 and 0.15 for yield in pods per plant, and 0.26, 0.19 and 0.40 for incidence of ‘bad’ pods, mostly due to black pod disease, caused by infection with Phytophthoraspp. The low heritability of single plant yield, which has been known for 80 years, has been widely overlooked in cocoa research and extension, compromising the success of clone selection programmes. The heritability of the incidence of black pod disease is high enough to justify mass selection where family level data are not available. The findings will be applied in a new large-scale programme in Ghana to select clones that are high yielding in the presence of P. megakarya. [ABSTRACT FROM AUTHOR]