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Surveying canopy attributes while conducting fieldwork in the rain forest is time-consuming. Low-cost imagery such as digital cover photography is a potential source of information to speed up the process of vegetation assessments and reduce costs during expeditions. This study presents an image-based non-destructive method to estimate canopy attributes of wild cacao trees in two regions of the rain forest in Colombia, using digital cover photography and machine learning algorithms. Upward-looking photography at the base of each cacao tree and machine learning algorithms were used to estimate gap fraction (GF), foliage cover (FC), crown cover (CC), crown porosity (CP), clumping index (Ω), and leaf area index (LAI) of the canopy cover. Here we used the cacao wild trees found on forestry plots as a case study to test the application of low-cost imagery on the extraction and analysis of canopy attributes. Canopy attributes were successfully extracted from the canopy cover imagery and provided 92% of classification accuracy for the structural attributes of the canopy. Canopy cover attributes allowed us to differentiate between canopy structures of the Amazon and Pacific rainforests sites suggesting that wild cacao trees are associated with different vegetation types. We also compare classification results for the computer extraction of canopy attributes with a digital canopy cover benchmark. We conclude that our approach was effective to quickly survey canopy features of vegetation associated with and of crop wild relatives of cacao. This study allows highly reproducible estimates of canopy attributes using cover photography and state-of-the-art machine learning algorithms such as deep learning Convolutional Neural Networks.

Ceratocystis wilt, currently one of the main diseases of cacao tree, is difficult to control, and the priorities are to find sources of resistance and to develop quick methodologies for evaluation. A quick methodology has been developed, the leaf disc (LD) method. In the present study, the resistance to C. cacaofunesta of 39 clones of cacao (Theobroma cacao L.), under field conditions and through the LD method has been evaluated. Woody branches and leaf discs (1.5 cm diameter) were inoculated with 30 μL and 20 μL, respectively, of the suspension with 3 × 104 CFU/mL of Ceratocystis cacaofunesta. Sixty days after inoculation in the field, inoculated and control branches were collected to evaluate the length, width, and area of the lesions. In leaf discs, the number of perithecia formed was counted after four days. Twenty-six new sources of resistance to C. cacaofunesta were selected through both inoculation methods. The LD method can be applied to a higher number of genotypes (increasing selection intensity) and much earlier than the field method.

The cacao tree surface is a substrate for various microorganisms. However, the species which live on the surface have hardly been described. The aims of this study were to evaluate the diversity of native cacao yeasts and to investigate their possible interaction with Moniliophthora perniciosa. A total of 225 yeast strains were isolated from the surface of leaves, fruits, and flowers of 20 cacao genotypes selected as carriers of resistance genes to M. perniciosa and M. roreri, which are the causal agents of witches’ broom (WB) and frosty pod rot diseases (FPR), respectively. The yeast isolates were molecularly identified based on sequences of the D1/D2 and ITS1/ITS4 regions of the rDNA. A total of 20 taxa distributed into 11 genera was found: Hannaella (23), Cryptococcus (9), Candida (11), Hanseniaspora (4), Kwoniella (1), Occultifur (3), Rhodotorula (17), Pichia (2), Sporobolomyces (1), Wicherhamomyces (1), and Yamadazyma (1). Phylloplane tissues showed the greatest richness: 55% of species and 81.82% of identified genera. Six yeast strains (Candida orthopsilosis—LEV 225; Hanseniaspora uvarum—LEV 162, 210, 211; and Rhodotorula paludigena—LEV 166, 168) exhibited the desired traits for a BCA agent: antibiosis in cocultivation, antibiosis by volatile compounds, germination inhibition, and production of killer toxins. This study is the first to show the great diversity of yeasts found in the cocoa phytobiome and the discovery of at least six microorganisms with excellent potential as BCA against cocoa witches’ broom disease.

Xylosandrus compactus is one of the significant beetle pests on perennial crops, which has become an increasing problem on cacao productivity and sustainability in South Sulawesi, Indonesia. The beetle is also known as ambrosia beetle due to the obligate association with symbiotic fungi. The beetle and infested plant parts were collected from infested Theobroma cacao in the field, then the beetles identified morphologically and the associated fungi isolated. In this study, we found that the beetles attacked all stages of cocoa growing in the field such as seedling, young trees and mature trees with visible symptoms including the appearance of round bore holes with powdery frass on the tree trunk and branches. Also, we found the beetle being distributed in three main cocoa areas in South Sulawesi. According to the beetle´s characteristic, the female has the black colour of the body (head and elytra), size 1–2 mm and the shining slope. Six types of fungi were isolated from infected plant parts and the beetle X. compactus: Fusarium-like colony (two isolates), Lasiodiplodia-like colony, Ceratocyctis-like colony and Diaporthe-like colony (two isolates). Among the fungi isolated, several fungi were known as the pathogen. The beetle and its associated fungi are responsible for the typical dieback symptoms, decline and sudden death inflicted on a number of cacao trees. The occurrence of X. compactus on cacao tree is reported for the first time from Sulawesi, Indonesia. The beetle pest infestation will become a significant threat to the future of the cacao industry in Sulawesi, Indonesia.

The effects of plantain shade and dry season irrigation on the growth, field survival, flowering and pod production of cacao was investigated. Treatments were a 2 by 2 factorial combinations of shade regimes (Unshaded/open sun and shaded) and irrigation intervals (5-day and 10-day intervals) arranged in a split-plot design. There was an unirrigated but shaded control. The shade regimes constituted the main plot while irrigation intervals were the sub-plot treatments. The growth, dry season survival, flowering and pod/bean yield characters of cacao were enhanced in the unshaded (open sun) compared with the shaded plants. The open sun treatment combined with 5-day irrigation produced the largest canopy development, flowering and pod production compared with shading-irrigation combinations. The shade-irrigation ameliorated microclimate and enhanced growth and development, flowering and uniform fruiting/pod production and total bean yield and reduced dry season mortality (whole tree death, branch and twig dieback). For the non-irrigated but shaded cacao, about 30% dry season mortality (branch and twig dieback) were obtained. Air temperatures within the cacao field were highest for open sun cacao followed by moderate and dense shade respectively. Flowers were more profuse for unshaded (open sun) cocoa compared with the shaded while the yield and yield components of cacao for each harvest dates and total pod and bean yields were significantly different between the unshaded and shaded cacao regimes. Trees that were irrigated at 5-day intervals produced significantly (P < 0.05) higher LAI, branching, flowers and pods compared with those irrigated at 10-day intervals. The 5-day irrigation interval significantly increased percentage of trees bearing flowers and pods, and produced larger number, and heavier pods and beans compared with the 10-day interval. The drip irrigation strategy adopted ameliorated dry season terminal drought (hydrothermal stresses) in cacao. This is a veritable tool to scale up growth, survival, establishment and flower/pod production.

Kosambi is a rural area, located in a high altitude area which belongs to Benua, South Konawe Regency, South East Sulawesi Province. The population is self-help transmigration from the province of South Sulawesi. Kosambi villagers generally burn and / or cut down forests to obtain land that will be used as planting areas. The land is not directly cultivated, but it is left first while collecting capital. This condition has the potential to cause erosion, and forest fires. Through the service funding scheme, the internal Community Partnership Program of Halu Oleo University in 2018 has successfully cultivated ¼ hectares of idle land from total of 2 hectares. Land management is performed through a partnership with patchouli farmers. At this initial stage, the land is only planted with patchouli. Patchouli planting patterns are arranged well so that the photosynthesis process occurs optimally. After six months, in August 2019, the first harvest was carried out. In the first harvest, 15 kg patchouli oil produced with a selling price of Rp. 505,000,- per kilogram. This year, cocoa planting will be tried as a protective crop in the new area planted with patchouli. Patchouli and cacao tree planting programs are expected to generate maximum farmer income in the future

The new EU regulation on cadmium (Cd) in cacao-derived products affects the cacao market worldwide. Here, we reviewed the journey of Cd from soil to chocolate bar and collated current data on the topic, giving due attention to data quality. Cacao bean Cd concentrations are typically about a factor two larger compared to the soil on which the cacao tree grows, this is high but not unusual and, therefore, the cacao plant is not classified as a Cd hyperaccumulator. Mean Cd concentrations in cacao beans range 0.02–12 mg Cd kg−1 and are markedly higher in Latin America, where more than half of cacao bean samples exceed the commonly applied threshold for export to the EU (0.60 mg kg−1). This regional enrichment is related to relatively high soil Cd concentrations in the young soils of Latin America. The source of Cd is, in general, likely geogenic rather than derived from phosphate fertilizers or contamination. A meta-analysis of 780 soil-plant paired data shows that soil Cd, soil pH and soil organic carbon largely explain cacao bean Cd concentrations. Detection of effects of cultivars, soil treatments or agronomic practices are strongly hampered by the spatial variability in phytoavailable soil Cd concentrations. Application of lime or biochar has the potential to lower bean Cd in acid soils. In the long-term, breeding low Cd cultivars likely provides the highest potential for mitigation but genetics and breeding research is currently limited by the lack of understanding of how Cd is loaded into the developing cacao fruit of this cauliflorous tree. Postharvest practices such as fermentation can slightly lower Cd concentrations in the final product but also play a large role in product quality. In the short term, mixing of cacao from different origins may be the most feasible strategy to meet the EU limits.

The cumulative effects of cacao swollen shoot virus (CSSV) mild strains N1 and SS365B on growth and yield of cacao (Theobroma cacao L.) were evaluated in a 12-year field trial at the Cocoa Research Institute of Ghana (CRIG). The treatments consisted of mixed hybrid cacao plants inoculated with N1 or SS365B prior to sowing and a non-inoculated control. Growth of mild strain-inoculated cacao plants did not differ significantly from that of non-inoculated plants. However, growth of N1-inoculated cacao plants was significantly higher than that of SS365B-inoculated ones. The yield of N1-inoculated cacao plants did not differ significantly from that of the non-inoculated plants. However, yield of SS365B-inoculated plants was significantly lower compared to N1-inoculated and the non-inoculated plants. In comparison with the non-inoculated control, yield was 77% and 20% lower in SS365B- and N1-inoculated cacao plants, respectively. Virus indexing conducted over a period of six months on randomly collected budwood from the field revealed the presence of mixed infection of CSSV strains in the field. Cacao tree mortality did not differ among the treatments. These results provide further evidence that the CSSV mild strain N1 is milder in its effect on cacao growth and yield than SS365B and suggest that the former would be a more suitable candidate for cross protection in cacao.

Artificial pollination management strategies are a potential solution to improving the livelihoods of smallholder cacao farmers by increasing crop productivity in situations when pollination services are limiting. However, field-based research trials evaluating the yield benefits of artificial pollination management strategies within intensified cacao systems are lacking. Thus, in an intensively managed cacao system, we evaluated the effects of artificial pollination condition (i.e., pollen genotype, pollination intensity, and pollination synchrony) on fruit development and yield in three high-yielding cacao clones. Artificial pollination, regardless of intensity, significantly increased fruit set and yield. Pollination synchrony had a significant effect on cherelle survivorship; older cherelles had greater survival rates across all developmental stages than younger cherelles. Yield differed between genotype crosses and varied according to the pollen donor used, highlighting the importance of understanding self- and cross-compatibility when selecting clones for cultivation. Pollination intensity had no significant effect on harvested yield, indicating that more rigorous research is needed to identify the pollination intensity required for optimized yield under artificial pollination conditions. We conclude that strategies to enhance flowering, pollination rates, and pollination synchrony while ensuring adequate tree nutrition may increase productivity in cacao. Future research evaluating numerous cacao clones across multiple years and locations may help us to understand the region-specific effects of intensive management strategies on the long-term sustainability of enhancing cacao tree productivity.

Most plant species depend upon insect pollination services, including many cash and subsistence crops. Plants compete to attract those insects using visual cues and floral odor which pollinators associate with a reward. The cacao tree, Theobroma cacao, has a highly specialized floral morphology permitting pollination primarily by Ceratopogonid midges. However, these insects do not depend upon cacao flowers for their life cycle, and can use other sugar sources. To understand how floral cues mediate pollination in cacao we developed a method for rearing Ceratopogonidae through several complete lifecycles to provide material for bioassays. We carried out collection and analysis of cacao floral volatiles, and identified a bouquet made up exclusively of saturated and unsaturated, straight-chain hydrocarbons, which is unusual among floral odors. The most abundant components were tridecane, pentadecane, (Z)-7-pentadecene and (Z)-8-heptadecene with a heptadecadiene and heptadecatriene as minor components. We presented adult midges, Forcipomyia sp. (subgen. Forcipomyia), Culicoides paraensis and Dasyhelea borgmeieri, with natural and synthetic cacao flower odors in choice assays. Midges showed weak attraction to the complete natural floral odor in the assay, with no significant evidence of interspecific differences. This suggests that cacao floral volatiles play a role in pollinator behavior. Midges were not attracted to a synthetic blend of the above four major components of cacao flower odor, indicating that a more complete blend is required for attraction. Our findings indicate that cacao pollination is likely facilitated by the volatile blend released by flowers, and that the system involves a generalized odor response common to different species of Ceratopogonidae.

Religion has a major impact on human–environmental relationships as evidenced by cultural responses to agricultural disease. In Belize, Protestant conversion has transformed traditional Mopan Maya environment relations and paved the way for the commercialization of formerly ritual crops. The changes in the spiritual importance of cacao and nature are reflected in farmers’ responses to the emergence of Monilia (Moniliophtora roreri), a fungal disease that attacks the fruits of the cacao tree (Theobroma cacao), the botanical source of chocolate. Traditionally, Mopan cacao farmers relied on ritual offerings to nature spirits to cure diseased trees. However, the widespread adoption of Protestant Christianity by many Mopan has led to the discontinuation of cacao rituals, the demystification of nature spirits, and increased reliance on agro-technical disease management. The decline of Mopan ritual offerings speaks more broadly to the transformation of indigenous environmental relations in the context of Protestant conversion and capitalist agricultural development.

O cacau é uma cultura perene de grande valor econômico na região norte brasileira, todavia apresentadificuldades de armazenamento e secagem que mantenham a qualidade do produto final. Com isso, o objetivo dopresente estudo foi dimensionar um equipamento para mensurar o ângulo de repouso de grão e analisar as sementes docacaueiro (Theobroma cacao L.), demonstrando suas características físicas ângulo de repouso, volume unitário,porosidade e esfericidade, com intuito de colaborar com futuros estudos de dimensionamento de silos, secadores ecorreias transportadoras. O trabalho foi conduzido no município de Tomé-Açu com a construção de um protótipo eposterior comparação a outro já estabelecido com 10 repetições, a esfericidade foi realizada com obtenção dos eixosortogonais de 15 sementes, o volume unitário considerou o volume de um elipsoide triaxial com 15 repetições,porosidade da massa de grãos foi determinada pelo método direto pela inserção de um fluido de óleo vegetal em umamassa conhecida. Os resultados foram submetidos ao teste de média (T) com p-valor

Chocolate and cocoa are manufactured from cacao beans produced by the cacao tree (Theobroma cacao). These products may contain cadmium (Cd), which originates from contaminated soil. Here, we surveyed the Cd concentrations in dark chocolate, milk chocolate, white chocolate and cocoa powder products purchased at retail stores in Japan, using inductively coupled plasma mass spectrometry. The Cd concentrations in these chocolate and cocoa powder products ranged from 0.00021 to 2.3 mg/kg and from 0.015 to 1.8 mg/kg, respectively. A weak positive correlation was found between the Cd concentration and the content of cocoa solids stated on the product labels. A comparison between these results and the maximum levels (MLs) set by the European Union revealed that the Cd concentrations in chocolate and cocoa powder products on the Japanese market exceeded the MLs for eight of the 180 chocolate products and 26 of the 140 cocoa powder products.

This chapter looks at both the Theobroma cacao tree and its cultivation. It covers cacao botany: its unusual habit of cauliflory, where the flowers, and hence the pods, arise directly from the trunk and main branches of the tree; pollination of its flowers, which is linked with the ecology of the rain forest in which it grows; and dispersal of its seeds, which is almost unique in its dependency on vertebrate animals such as monkeys, bats, and squirrels. The chapter also deals with the cultivation of cacao, mostly by smallholder farmers on individual, family-managed farms, typically 0.5 –7 ha in size, in the lowland tropical regions of Latin America, West Africa, and Indonesia. Finally, the chapter examines the impact of the increasing demand for chocolate on the push towards the intensification of cocoa cultivation, threatening to shift production even further from the traditionally managed, sustainable cultivation systems of the past.

Understanding how the spatial organization of diversified plant communities alters their performance is an important step in designing and managing diversified agroecosystems. The high level of spatial heterogeneity in tropical agroforests makes this task challenging. In 19 agroforestry plots in Talamanca (Costa Rica), we analyzed the effect of the structure of the plant community in the neighborhood of each individual cacao tree and banana plant on their growth and yield parameters. We developed an individual-based analysis in two steps. First, we selected without a priori the distance at which the number of neighboring plants of a given functional group (banana plants, cacao trees, fruit trees, or wood trees) best explained the proportion of attainable yield (PAY) of cacao and banana plants. In a second step, we tested the significance of the abundances of the four groups of plants in a complete model that predicted the PAY of banana and cacao plants. The abundance of neighboring plants did not increase banana PAY except in the case of other banana plants, suggesting that banana plants yield better when aggregated. All other groups of plants tended to reduce both banana and cacao PAY. In the case of wood trees, these trends were not significant. Interestingly, our results suggests that it is possible to associate banana plants and cocoa trees to moderate densities of other plants without reducing their yield. The two complete linear models predicted about 60 % of the variance of the average response of the PAY to the neighboring plant assemblage. We suggest that in the future, it would be important to differentiate processes (resources partitioning, pest and diseases) inside our statistical approach. While requiring much more data, it could be useful to address the effect of cultural practices.

Cocoa, derived from the Theobroma cacao tree, contains, among other compounds, methylxanthines such as theobromine, and polyphenols mainly flavonoids belonging to the flavanol family. It has been reported that cocoa consumption is beneficial for cardiovascular and brain health, in the protection against cancer, but it remained to know what happen in allergic diseases. In this talk, I will explain the influence of a cocoa-enriched diet in two models of allergy in rats, including the effects on the anaphylactic response. Moreover, I will introduce the results using particular cocoa populations. Apart of the preclinical studies developed in rats, the results of an observational study in university students are included. In summary, although more studies are needed, it will be demonstrated the potential of cocoa intake in the prevention of allergic reactions.

Water sprouts are one of the causes of cherelle wilt in cacao plants, thus water sprouts must be pruned regularly. On the other hand, the number of cacao workers is increasingly reduced because young people prefer to work in urban areas. Therefore, an automation system to prune water sprouts on cacao plants is needed. Machine vision technology plays an important role in detecting water sprouts in the automatic pruning system in the plantation area. In this paper, the Mask R-CNN (Region-based Convolutional Neural Network) method is used to detect and segment water sprouts from images taken at a cacao plantation. The obtained data consist of 150 images which are for a training dataset of 120 images and a testing dataset of 30 images. To determine the system performance, the threshold parameter in the detection step was tested from 0.1 to 0.9. The best results are obtained at a threshold of 0.6 with an F1score of 0.907. This result shows that the Mask R-CNN method is able to detect water sprout properly.

Resumen El cultivo de cacao se mantiene en auge en Costa Rica; sin embargo, las autoridades europeas han establecido regulaciones a la importación de los derivados del cacao; las cuales iniciaron en enero de 2019 con la fijación de niveles de concentración máximos permitidos de cadmio. El objetivo de este trabajo fue determinar concentraciones de cadmio en suelo, raíz, hoja y en grano seco no fermentado de cacao en dos regiones productoras de este cultivo en el país. El presente estudio exploratorio se realizó en 2017 y 2018, determinándose la presencia de cadmio en las partes raíz y hoja del árbol de cacao, y en el grano. La información generada permitió determinar que parte de la producción de cacao se encuentra localizada en un entorno donde los órganos raíz y hoja pueden bioacumular este metal y transferirlo a la mazorca donde se detectó concentraciones de cadmio en granos, en un rango de 0 a 8,70 mg/kg. El porcentaje de muestras positivas en granos fue mayor en la Región Sur con 89,47%, mientras que en la Norte fue 33,33%. Sin embargo, en los análisis de suelos hechos en las muestras de los mismos sitios donde se muestrearon los órganos del árbol, solo se encontró en la Región Sur con un porcentaje muy bajo de muestras positivas, tres muestras de un total de 19, quizás debido a que el límite mínimo de detección para suelo propuesto por el laboratorio fue de 1 mg/kg. Abstract Cocoa cultivation is booming in Costa Rica; however, European authorities have established regulations for the importation of cocoa derivatives; which started in January 2019 with the fixation of maximum allowed concentration levels of cadmium. The objective of this study was to determine concentrations of cadmium in soil, root, leaf and non-fermented dry cocoa beans in two regions producing this crop in the country. The present exploratory study carried out in 2017 and 2018, determining the presence of cadmium in the root and leaf parts of the cacao tree, and in the grain. The information generated allowed finding that part of the cocoa production is located in an environment where the root and leaf organs can bioaccumulate this metal and transfer it to the cob where the concentrations of cadmium were detected in beans in a range of 0 to 8, 70 mg / kg. The percentage of positive samples in beans was higher in the South Region with 89.47%, while in the Northern it was 33.33%. However, in the analyzes of soils made in the samples from the same sites where the tree organs were sampled, only a very low percentage of positive samples were found in the Southern Region, three samples out of a total of 19, perhaps due the minimum detection limit for soil proposed by the laboratory was 1 mg / kg.

International audience; Manipulating plant functional diversity to improve agroecosystem multifunctionality is a central challenge of agricultural systems world-wide. In cocoa agroforestry systems (cAFS), shade trees are used to supply many services to farmers, yet their impact on soil functioning and cocoa yields is likely to vary substantially among tree species. Here we compared the impact of five shade tree species (Canarium schweinfurthii (Canarium), Dacryodes edulis (Safou), Milicia excelsa (Iroko), Ceiba pentandra (Kapok tree), Albizia adianthifolia (Albizia)) and unshaded conditions on the functioning of poor sandy savanna soils within eight cocoa farms in Central Cameroon. We assessed the effects of plant functional traits, leaf litterfall and fine root biomass on a range of soil functions and on cocoa yield. Shade trees generally improved soil pH, NH4+, NO3- and Olsen P content, biomass production of bioassays and soil total C and N content, while leaving cocoa yields unchanged. However, these effects varied largely among species. Improvements of soil functions were low under the two fruit trees (Canarium and Dacryodes), medium under the legume tree Albizia and high under the two timber trees (Milicia and Ceiba). Low litter recalcitrance was most strongly associated with increases in soil fertility indicators such as N and P availability, whereas soil C and N content increased with litter Ca restitution. Synthesis and applications. We demonstrate that cocoa agroforest multifunctionality is substantially influenced by the functional traits of shade tree species. Shade tree species with the most dissimilar traits to cocoa (cocoa showing the lowest leaf litter quality) showed the largest improvement of soil functions. Therefore, selection of shade trees based on their functional traits appears as a promising practice to adequately manage soil functioning. In order to fully assess the beneficial role of shade trees in these agroecosystems. Future research will need to extend this approach to other below-ground traits and other aspects of multifunctionality such as long-term cocoa health and yield.

Cocoa mirids, Sahlbergella singularis and Distantiella theobroma, are the most economically important insect pests of cocoa in West and Central Africa, where they can cause up to 40% losses in cocoa yields. Sahlbergella singularis is the most common species in Cameroon and was therefore targeted in this study. During a two-year trial in 15 cocoa plantations in Ayos and Konye, in the Centre and Southwest regions of Cameroon respectively, the most effective colour – white, purple or green – of sex pheromone traps was examined for integration into mirid management programmes. Similar temporal patterns in S. sahlbergella male trap catches were observed with all three colours, but the green trap caught more S. singularis (Ayos: 0.968 ± 0.091 [SEM]; Konye: 0.640 ± 0.076/trap/month) compared with purple traps (Ayos: 0.674 ± 0.068; Konye: 0.441 ± 0.058), and white traps (Ayos: 0.467 ± 0.049, Konye: 0.253 ± 0.041). Trap reflectance showed wavelength peaks typical for purple in both short (approximately 380–480 nm) and long wavelengths (>650 nm), and ~530 nm for green. Reflectance peaks exceeded 100% of the incident light in the 400–450 nm range from the white, suggesting the presence of optical brighteners. Trap catches support the hypothesis that S. singularis ocelli are more responsive to light of shorter wavelengths. Despite the low attractiveness of the sex pheromone to S. singularis, a optimisation of the colour of the trap can improve S. sahlbergella monitoring, mass trapping, and other control measures which could ultimately lead to reductions of insecticide use and to conservation of beneficial arthropods, particularly cocoa flower pollinators that are critical for improving cacao tree productivity.

Cadmium (Cd) is a non-essential trace metal, highly toxic to plants, animals and humans. Its mobility in the soil is high and it is transferred with relative ease to crops. European Food Safety Agency (EFSA) has identified the consumption of chocolate as a source of Cd contamination, and established maximum Cd limits allowed in cacao-based products. Therefore, research related to tolerance and reduction of Cd toxicity in a cacao becomes important. The main objective of the present study was to systematize the main factors that interfere in the uptake of soil Cd by the cacao tree and its strategies for tolerance to toxicity. A systematic review of the literature was conducted using six databases for academic research (Google Academic, PubMed, Springer, CAPES Periodical, Scielo and Science Direct). To avoid publication bias, a previously established protocol and inclusion and exclusion criteria were used. The main factors related to the uptake of soil Cd by the cacao tree were soil pH, soil Cd availability, genotype, the geographical location, agronomic factors such as phosphate fertilizersand Cd interaction with other minerals/metal nutrients such as Zn and Mn present in the soil. To reduce the toxicity of this metal, cocoa promotes some tolerance strategies such as uptake and transfer of Cd from the root to the shoot, molecular and biochemical changes, Cd partition between plant organs and Cd sequestration at the cellular level. So, this systematic review contributed to the acquisition of knowledge for the genetic improvement of cacao tree, concerning toxicity tolerance strategies and reduction of soil Cd uptake.

As a plant-specific transcription factor, the NAC (NAM, ATAF1/2 and CUC2) domain protein plays an important role in plant growth and development, as well as stress resistance. Based on the genomic data of the cacao tree, this study identified 102 cacao NAC genes and named them according to their location within the genome. The phylogeny of the protein sequence of the cacao tree NAC family was analyzed using various bioinformatic methods, and then divided into 12 subfamilies. Then, the amino-acid composition, physicochemical properties, genomic location, gene structure, conserved domains, and promoter cis-acting elements were analyzed. This study provides information on the evolution of the TcNAC gene and its possible functions, laying the foundation for further research on the NAC family.

SUMMARYIn Côte d'Ivoire, the world's largest cocoa producer, cacao (Theobroma cacaoL.) is usually grown from seed. The genetics consist of a mix of amelonado, trinitario and selected hybrids. This mix of varieties generates high phenotypic variabilities, including variability in tree productivity, within cacao populations in both smallholder and industrial plantations. Tree-to-tree variability in yield has been reported in cacao breeding trials under different environmental conditions. However, it has never been considered a limiting factor for agronomical performance of seedling-based cacao plantations. Around 10 000 cacao trees from seven plots under different environmental conditions in a cacao plantation in Côte d'Ivoire were monitored for 2 years. Pod production of individual trees was recorded and annual average tree pod yields were assessed. High heterogeneity in cacao-tree yields was observed in all plots, with coefficients of variation ranging from 56 to 102%. The distribution of cacao-tree yields in each plot was positively skewed. Analysis of these distributions showed that unproductive trees represented a significant proportion of cacao tree populations (7%), and the 20% least productive trees accounted for 3% of production. The 20% most productive trees were responsible for 46% of the total pod production of a plot. This heterogeneity reflects a major imbalance in the agronomical performances of low- and high-yielding trees and also represents possible efficiency gaps in seedling-based cacao plantations, which could be overcome through innovative corrective strategies, opening new pathways for improvement of cacao-based cropping systems.

BACKGROUND: Using conventional pesticides in crop protection has raised serious environmental concerns and there is therefore a need for integrated pest management (IPM) methods. In this paper, we found that the spacing of trees can impact disease, which could result in a reduction in pesticide applications and may act as a potential IPM method. We studied Frosty Pod Rot (FPR) in 20 cacao agroforests in Costa Rica (Upala region). RESULTS: Using a generalized linear mixed model, we analyzed the impact of the neighborhood composition and distance from a studied cacao individual on its individual FPR incidence. We found that the number of cacao tree neighbors in a radius of 3.7 m and the number of fruit trees in a radius of 4.3 m had a significant negative influence on the incidence of FPR on individual cacao trees. Moreover, cacao tree neighbors had the most significant local influence compared to the neighborhood of other taller categories such as fruit or forest trees. CONCLUSION: The mechanisms involved are related to the barrier effect, due to the effectiveness of the cacao tree's architecture as an efficient barrier against FPR spore dispersal. This paper provides new insights into optimization of the spatial environment around each host as an original IPM method. © 2017 Society of Chemical Industry. (Resume d'auteur)

Abstact. Probowati W, Somowiyarjo S, Hartono S. 2019. Molecular characterization of Mosaic Virus From the cocoa trees showing mosaic symptoms in Yogyakarta, Indonesia. Biodiversitas 20: 3698-3704. Indonesia is the world's second-biggest producer of cacao after Ivory Coast with its cacao plantations spreads over 1,652 million hectares and mostly managed by smallholders. Cacao as a beneficial commodity can provide job opportunities for over 1.64 million people, with its contribution of more than US-$ 1.6 billion/year to national income. However, pest and disease infections are inevitably common constraints for the cacao cultivators. One current disease is caused by Cacao Swollen Shoot Virus (CSSV). Despite its noticeable symptoms on the cacao trees suffering from the disease, the knowledge on both the virus existence and the prevention steps in dealing with it is lacking. The information on the diversity of mosaic virus will help us to comprehend its epidemiologic development and the needed countermeasures, as well as its evolution. This research is intended to study the mosaic disease virus molecularly, the virus was obtained from DR1 clones from Kalibawang cacao plantation in Kulon Progo, Yogyakarta. The virus morphology was observed using a transmission electron microscope applying quick dipping method. The PCR analysis with conserved region ORF1 primers was conducted to detect the viral existence in the infected trees. The identification of CSSV molecular characters was undertaken using PCR sequencing analysis which was then examined using BioEdit and Mega5 programs to initiate a relationship dendrogram. The result showed that the DR1 cacao tree clones from Kalibawang were infected by mosaic virus with mild visual severity of leaf typical symptom. From the electronic microscope observation, a ±100 nm rod-shaped viral particle with a diameter of 15.3 mm was found. On the molecular level, the cause of mosaic symptom has CSSV amplified at conserved regions with size 375 bp. The results are the first report confirming that the molecular cause of cacao mosaic disease in Indonesia is CSSV. The molecular characters of CSSV in Yogyakarta are very different from those found abroad.