Cacao Production Research Articles

Physicochemical characteristics of cacao (Theobroma cacao L.) soils in Colombia: Are they adequate to improve productivity?

In Colombia, cacao farms are located mainly in areas with edaphoclimatic limitations. The predominant soil fertility characteristics from small cacao farms in 13 provinces were evaluated. A total of 635 soil samples (0-20 cm) were taken between 2011 and 2013 from the main cacao producer regions in Colombia. The number of samples was assigned based on the regional cacao production. The resulting data were analyzed with a linear regression model using pH as the dependent variable and soil chemical and physical parameters as the independent variables. Soil texture ranged between 14 and 40% clay, and 31 and 65% sand. Bulk density ranged between 1.07 and 1.28 Mg m-3 with a calculated porosity between 48.8 and 55.0%. There was no evidence of soil compaction. The national pH ranged between 3.9 and 7.9 and was negatively correlated with Al+3 content (R2 = 0.68) and Al saturation (R2 = 0.80) and redicts Al saturation in the range of available Al up to pH >5.2- 5.5. In this range, available P (as P2O5) was lower than 12 mg kg-1 and was accepted as a minimum value for a sustainable production. With 4.0 cmolc kg-1 of Ca and 60% saturation of the effective cation exchange capacity (ECEC). A minimum ECEC is proposed at 6.0 cmolc kg-1. A reference table for soils in Colombia is proposed as a guide for the establishment and management of productive and sustainable plantations.

The importance of non-monetary cost in start-up and annual cacao (Theobroma cacao L) production activities in Santander, Colombia

Based on a double-phase methodology (grouping by cluster method and costing) the costs of three activities of cacao establishment and annual management in San Vicente de Chucuri and El Carmen de Chucuri (Santander, Colombia) were structured. The grouping phase identified two productive typologies, one with low technification level and another with a medium level; moreover, technification levels were corroborated through cost structuring, in which, for all the activities, the medium technification typology generated higher average values than the low one. General cost structures showed that the most important item is labor, followed by inputs and plant material. The disaggregation of costs into monetary and non-monetary (implicit cost) showed that producers with low technification and low frequency of input use present 35% of non-monetary costs per tree, while producers with some level of crop management and relatively high execution of activities have a slightly higher non-monetary cost, 45% of the average total cost per tree. Within non-monetary costs, the labor (mainly family labor) contributed, on average, to 34% of the total cost structures, which constitutes a risk management factor when defining the financial equilibrium point of the cacao production activity.

The physiological responses of cacao to the environment and the implications for climate change resilience. A review

Cacao (Theobroma cacao L.) is a tropical perennial crop which is of great economic importance to the confectionary industry and to the economies of many countries of the humid tropics where it is grown. Some recent studies have suggested that climate change could severely impact cacao production in West Africa. It is essential to incorporate our understanding of the physiology and genetic variation within cacao germplasm when discussing the implications of climate change on cacao productivity and developing strategies for climate resilience in cacao production. Here, we review the current research on the physiological responses of cacao to various climate factors. Our main findings are as follows: (1) water limitation causes significant yield reduction in cacao, but genotypic variation in sensitivity is evident; (2) in the field, cacao experiences higher temperatures than is often reported in the literature; (3) the complexity of the cacao/shade tree interaction can lead to contradictory results; (4) elevated CO2 may alleviate some negative effects of climate change; (5) implementation of mitigation strategies can help reduce environmental stress; and (6) significant gaps in the research need addressing to accelerate the development of climate resilience. Harnessing the significant genetic variation apparent within cacao germplasm is essential to develop modern varieties capable of high yields in non-optimal conditions. Mitigation strategies will also be essential, but to use shading to best effect shade tree selection is crucial to avoid resource competition. Cacao is often described as being sensitive to climate change, but genetic variation, adaptive responses, appropriate mitigation strategies and interactive climate effects should all be considered when predicting the future of cacao production. Incorporating these physiological responses to various environmental conditions and developing a deeper understanding of the processes underlying these responses will help to accelerate the development of a more resource use efficient tree ensuring sustainable production into the future.

PRESERVASI SENYAWA FENOLIK DAN ANTIOKSIDAN PADA PROSES SANGRAI BIJI KAKAO DENGAN MENGGUNAKAN VACUUM DRYING OVEN

Indonesia is the biggest cacao producer in Asia and third biggest in the world, however, Indonesian cacao has low quality due to partial fermentation. Late 2010 almost all of the cacao production is exported in dried beans with a lower price than world’s cacao price rate. Export tax of cacao beans policy was changed to 15% in 2011 which conduce replacement of cacao beans export to finished product export. Innovation in cacao beans processing is important to develop escepially for agroindustry field. Cacao beans roasting process is important thing in chocolate processing. During the roasting process, phenolic compounds and methylxanthine of cacao beans were denatured. Vacuum drying oven is one of the alternative process which can preserve bioactive compounds. Thus, the aim of this research is to give information about effect of vacuum drying oven in total phenolic and antioxidant activity. Analysis methods used were total phenolic and antioxidant activity (IC-50) analysis. The result shown that vacuum drying oven has significant effect on total phenolic and antioxidant activity with three times higher in concentration than conventional method. The highest antioxidant activity and total phenolic content at 80°C and 75 minutes. Therefore, vacuum drying oven can be used as an alternative method with an advantage like preserve bioactive compound in cacao beans.Keywords: antioxidant, cacao, phenolic, roasting, vacuum drying

Glucocorticoid receptor-regulated TcLEC2 expression triggers somatic embryogenesis in Theobroma cacao leaf tissue.

Theobroma cacao, the source of cocoa, is a crop of particular importance in many developing countries. Availability of elite planting material is a limiting factor for increasing productivity of Theobroma cacao; therefore, the development of new strategies for clonal propagation is essential to improve farmers’ incomes and to meet increasing global demand for cocoa. To develop a more efficient embryogenesis system for cacao, tissue was transformed with a transgene encoding a fusion of Leafy Cotyledon 2 (TcLEC2) to a glucocorticoid receptor domain (GR) to control nuclear localization of the protein. Upon application of the glucocorticoid dexamethasone (dex), downstream targets of LEC2 involved in seed-development were up-regulated and somatic embryos (SEs) were successfully regenerated from TcLEC2-GR transgenic flower and leaf tissue in large numbers. Immature SEs regenerated from TcLEC2-GR leaves were smaller in size than immature SEs from floral tissue, suggesting a different ontogenetic origin. Additionally, exposure of TcLEC2-GR floral explants to dex increased the number of SEs compared to floral explants from control, non-transgenic trees or from TcLEC2-GR floral explants not treated with dex. Testing different durations of exposure to dex indicated that a three-day treatment produced optimal embryo regeneration. Leaf derived SEs were successfully grown to maturity, converted into plants, and established in the greenhouse, demonstrating that these embryos are fully developmentally competent. In summary, we demonstrate that regulating TcLEC2 activity offers a powerful new strategy for optimizing somatic embryogenesis pipelines for cacao.

Preliminary Phytochemical Screening (Qualitative Analysis) of Cacao Leaves (Theobroma cacao L.)

One of the important processes of cocoa plants growing is pruning. It aims to eliminate sick, broken, or the appearance of water buds disturbing the cacao production. The period of pruning is varios. The various periods of pruning lead to leave wide waste of leaves, stems, and twigs. Yet the waste would not been used to other activities, only a small portion of the waste used as natural fuel (stems and twigs) and cocoa leaves waste as animal feed. Phytochemicals naturally present in every part of plants range from leaves, stem bark, fruits to roots. Secondary metabolites are natural products from plants which include alkaloid, flavonoid, steroid, terpenoid, sapponin compounds, etc. This study performed some phytochemical characterisations. It have confirmed that cacoa leaves consist some of bioactives compounds which are potential for furhter activities in pharmaceutical disease.

Effet de la diversité végétale sur la productivité des systèmes de culture multi-espèces : une étude de cas sur les systèmes agroforestiers à Talamanca, Costa Rica

Talamanca, au Costa Rica, avec ses systèmes de culture variés, est l'une des régions les plus diversifiées du pays sur le plan écologique. L'environnement naturel a toujours fait partie intégrante de la vie des populations autochtones de cette région. Les agroforêts tropicales sont de plus en plus étudiées comme une alternative durable aux systèmes modernes d'agriculture intensive.Cependant, les connaissances sont encore insuffisantes sur la façon dont la diversité fonctionnelle dans les plantes affecte les processus qui soutiennent la production, ce qui nécessite le développement de nouvelles approches. L'objectif de cette thèse était de quantifier la relation entre diversité et productivité dans le cas des systèmes agroforestiers de Talamanca, dans une perspective de recherche appliquée. Tout d'abord, une méta-analyse a été effectuée pour étudier la question de la production et de la diversité dans un très large éventail de systèmes à travers le monde. Nous avons ensuite réalisé une étude approfondie de la diversité et de la productivité de 180 parcelles (100 m² chacune) situées dans 20 champs de la région de Talamanca. Nous avons estimé la productivité de chaque plante dans ces champs pendant un an de travail sur le terrain. Nous avons ensuite développé une analyse des individus pour déterminer si le nombre de plantes voisines d'une espèce donnée expliquait le rendement potentiel des bananiers ou des cacaoyers (les principales cultures de rente de ces systèmes agroforestiers). Il est intéressant de noter que les arbres occupant les strates supérieures ont eu un effet plus faible que ceux des strates inférieures, ce qui suggère que des densités modérées de grands arbres pourraient être compatibles avec une productivité élevée de bananes et de cacao. Du point de vue de la recherche appliquée, cette étude a permis de quantifier la productivité globale de ces systèmes et de déterminer dans quelle mesure leur diversité fonctionnelle les modifie.

Soil properties and agronomic factors affecting cadmium concentrations in cacao beans: A nationwide survey in Ecuador

Recent cadmium (Cd) regulation in chocolate threatens the sustainability of cacao production in Southwest America. Cadmium contamination in cacao beans has not been assessed at a country level. A nationwide survey was conducted in Ecuador to identify the spatial distribution of Cd in cacao beans, as well as soil and agronomic factors involved. Paired soil and plant samples (pods and leaves) were collected at 560 locations. Information on agronomic practices was obtained through a prepared questionnaire for farmers. Total soil Cd averaged 0.44 mg kg−1 which is typical for young and non-polluted soils. Mean Cd concentration in peeled beans was 0.90 mg kg−1 and 45% of samples exceeded the 0.60 mg kg−1 threshold. Bean Cd hotspots were identified in some areas in seven provinces. Multivariate regression analysis showed that bean Cd concentrations increased with increasing total soil Cd and with decreasing soil pH, oxalate-extractable manganese (Mnox) and organic carbon (OC) (R2 = 0.65), suggesting that Cd solubility in soil mainly affects Cd uptake. Bean Cd concentration decreased a factor of 1.4 as the age of the orchard increased from 4 to 40 years. Bean Cd concentration was inconsistently affected by genotype (CCN-51 vs. Nacional), pruning or application of fertilizers. It is concluded that the relatively larger bean Cd concentrations in Ecuador are related to the high Cd uptake capacity of the plants combined with their cultivation on young soils, instead of Cd depleted weathered soils. Mitigation strategies should consider the application of amendments to modify such soil properties to lower soil Cd availability. There is scope for genetic mitigation strategy to reduce bean Cd, but this needs to be properly investigated.

Mode of Inheritance and Combining ability studies on Epicuticular wax Production in Resistance to Black pod disease in Cacao (Theobroma cacao L.)

Abstract Black pod caused by Phytophthora species is a devastating disease of cacao (Theobroma cacao L.) in production regions worldwide. Breeding for cacao genotypes resistant to black pod disease is crucial for sustainable cocoa production and profitability. Although breeding programmes in the past have made considerable efforts in improving resistance of cocoa genotypes with diverse genetic background, the disease continues to cause unacceptable yield losses in cacao production. To understand the mode of inheritance of epicuticular wax on the surface of cocoa pod known to play a major role in resistance to black pod disease, a 6 × 6 full diallel and a M x N (6 × 4) mating designs were used and data was analysed using Griffing’s method I model I approach and the North Carolina design –II approach, respectively. The results of the two mating designs were consistent and showed that epicuticular wax on leaf and pod surfaces of cacao were under the control of additive genetic effects. The non-additive effects were generally much smaller compared to the additive genetic effects. The significant association between GCA estimates of parents and their means indicates that parental values could be used as indicators of progeny performance. The best general combiners for epicuticular wax load on leaf and pod surfaces were Pa7/808, T60/887 and Pa 150. The larger additive components and heritability observed in this study, indicates that pedigree selection could be used to develop cacao cultivars with high amount of epicuticular wax on pod surface to enhance resistance to black pod disease.

Cacao plantations on Sulawesi Island, Indonesia: I—an agro-ecological analysis of conventional and organic farms

The cacao plantation largely contributes to the Indonesian agricultural economy, and the systems with less environment impact have become fundamental for the local farmers. The current research made a general agro-ecological evaluation of six cacao farms in Sulawesi-Indonesia cultivated under conventional systems and organic management, here referred to as environmental friendly systems (EFS). Ten agro-ecological parameters, the number of fruits per area, the rate of infection (RI), number of seeds per fruit, and seed weight per fruit were evaluated. Furthermore, plant mineral nutrition was also analyzed, including the estimation of diagnosis recommendation integrated systems. The overall data indicated that RI in the conventional systems was lower than that in the EFS. The density of dead plant materials showed negative correlations with the area of weeds and density of weeds. The density of dead plant materials, concentrations of Mg and Fe showed a positive correlation with productivity. In addition, Fe showed negative correlations with weed area and density. The nutrient balance index also showed that in Parigi and Palolo areas, the plants were well stabled in terms of mineral nutrition. These results suggest that some agro-ecological parameters can function as cacao production indicators, especially the biomass and dead leaves together with plant mineral nutrition (Mg and Fe).

Polyphenols: Inflammation.

Polyphenols widely distributed in plants, fruits and vegetables have received considerable attention on account of their physiological functions, including their antioxidant and anti-inflammatory properties. Some antioxidant components of cacao liquor prepared from fermented and roasted cacao beans, which is a major ingredient of cocoa and chocolate products, have been characterized as flavan-3-ols and procyanidin oligomers. This review focuses on a specific group of (-)-epicatechins and their oligomers, the procyanidins, in cacao products. Dietary polyphenols in cacao products have been shown to reduce hypertension, reduce platelet aggregation, improve serum lipids, and lower the incidence of atherosclerosis in animal studies and clinical trials. The intake of cacao products reduces hypertension and atherosclerosis on account of their physiological functions as antioxidants and anti-inflammation agents, indicating the mechanisms of prevention of hypertension and atherosclerosis by polyphenols.

CALLUS INDUCTION OF CACAO CLONE SULAWESI 1 ON VARIOUS CONCENTRATIONS OF 2,4 -D AND COCONUT WATER VIA IN VITRO CULTURE

Cacao is one of important plantation crops grouped in the Sterculiaceae family. Sulawesi is the main area of cacao production and has a number of superior clones, such as Sulawesi 1 and Sulawesi 2. Based on data in 2012/2014 cacao production to consumption reached 174,000 tons, while in 2013/2014 was projected a deficit of 115,000 tonnes. Nonetheless, cacao agribusiness in Indonesia is still facing complex problems, among others gardener productivity is still low due to borer attacks cacao, the quality of products and the number is still low and still not optimal development of cacao products and providing superior amount of cacao seedlings. The primary problem of cacao production recently is low productivity. The main cause of low cacao productivity in Central Sulawesi is the use of inferior clones. To enhance cacao productivity, it is crucial to use cacao clones having high genetic potential via tissue culture or micropropagation techniques. The aim of this experiment was to assess the effect of different concentrations of 2,4-D and coconut water on the growth of cacao callus via in vitro culture. This experiment used Completely Randomozed Block Design in factorial patteren with treatments tested namely 2,4-D and coconut water concentrations. The concentrations of 2,4-D tested including 1 ppm, 2 ppm and 3 ppm, whilst coconut water concentrations tested consisting of 10%, 15% and 20%, and therefore there were 3 x 3 = 9 treatment combinations. Each treatment utilized 4 replications; and each unit combination used 5 explants (staminodia). Results of this experiment indicated that the addition of 3 ppm 2,4-D and 10% coconut water had a highly significant effect on the callus color 4 weeks after culture. The addition of 3 ppm 2,4-D in culture media showed a significant effect on callus color 4 weeks after culture, but had an insignificant effect on the callus formation, callus color 8 weeks after culture an callus texture. Supplementation of 20% coconut water had a significant effect on callus texture 8 weeks after culture, whilst the addition of 10% coconut water showed a significant effect on callus color 4 weeks after culture.

Mapping of a Major QTL for Ceratocystis Wilt Disease in an F1 Population of Theobroma cacao.

Cacao is an important crop, its beans are key raw materials for the chocolate and cosmetic industries. Ceratocystis wilt of cacao (CWC) caused by Ceratocystis cacaofunesta is a lethal disease for the crop. Therefore, the selection of resistant cacao varieties is one of the viable ways to minimize losses in cacao production. In this paper, we described the identification of a major QTL associated with CWC in an F1 mapping population from a cross between a resistant, “TSH 1188,” and a susceptible genotype, “CCN 51.” A set of 266 trees were genotyped using 3,526 single nucleotide polymorphic markers and then multiple QTL mapping analyses were performed. Two QTLs were identified on chromosomes IV and VI. The major QTL was located at 20 cM from the top position of chromosome VI, accounting for more than 60% of the phenotypic variation. The favorable allele T1, with haplotype GTT, came from the “TSH 1188” parent. It was evident that the haplotype combination T1C2 on chromosome VI was the most significant for resistance, since 93% of resistant trees had this haplotype. The major QTL converged to a genomic region of 739.4 kb that harbored nine candidate genes, including two major classes of resistance genes, which would make them the primary candidates involved in the resistance to CWC. The haplotypes detected are now used to improve the efficiency and precision of the selection of resistant trees in cacao breeding.

Path analysis of phenotypic traits in young cacao plants under drought conditions.

Drought is worldwide considered one of the most limiting factors of Theobroma cacao production, which can be intensified by global climate changes. In this study, we aimed to investigate the phenotypic correlation among morphological characteristics of cacao progenies submitted to irrigation and drought conditions and their partitions into direct and indirect effects. Path analysis with phenotypic plasticity index was used as criteria for estimation of basic and explanatory variables. The experiment was conducted in a greenhouse at the Cacao Research Center (CEPEC), Ilhéus, Bahia, Brazil, in a randomized block 21 x 2 factorial arrangement [21 cacao progenies obtained from complete diallel crosses and two water regimes (control and drought)] and six replications. In general, drought conditions influenced biomass production in most progenies, causing significant reductions in total leaf area, leaf number, leaf biomass, fine-roots length (diameter <1 mm), root volume and root area for considered drought intolerant. All progenies showed alterations in growth due to drought. Phenotypic plasticity was most strongly pronounced in root volume. Stem and root diameters, as well as stem dry biomass were the growth variables with the greatest direct effects on root volume under drought conditions, these characters being indicated in screening of cacao progenies drought tolerant.

Cocoa Production Stability in Relation to Changing Rainfall and Temperature in East Java, Indonesia

Climate change as indicated by rising temperature and changing rainfall pattern has been known to affect cacao production in many production countries. However, studies on the effects of rainfall and temperature variability on the cacao production are rarely reported in Indonesia. Hence, the objective of this study is to evaluate the stability of cocoa production in relation to rainfall and temperature variability in order to develop sustainable production under climate change scenario. Research was conducted at a state owned company in Jember District, East Java, Indonesia from February to June 2015. Production and climatic data of 2010-2015 were evaluated using simple regression and correlation analysis. Results revealed that productivity fluctuated among months and among years. However, the fluctuation among months (s2 = 117.076) was lower than among years (s2 = 311.225). Rainfall and temperature showed variability among months and among years; and the fluctuation among months was lower in both rainfall and temperature. Rainfall at one to four months before harvest correlated with production (r=0.400-0.671; P= 0.000 to 0.001) and temperature at two to four months before harvest determined cocoa production (r=0.371-0.412; P=0.001-0.003). High monthly cocoa production coincided with decreasing temperature and rainfall for 4 to 5 months during pod development. The presented study implies that both short and long term strategies should be implemented under climatic variability to sustain cocoa production. It is recommended to apply production technology to stabilize micro climate temperature and to minimize the impact of high rainfall such as shade plant and canopy manipulation.

Cellulose Compound of Cacao Waste and Chemical Composition of Cacao Vinegar with GC-MS Method

&lt;p&gt;Potential of cacao resources at Indonesian is very dependent on the production of cacao produced by farmers and plantation availability. However, the cacao processing results are still not optimal to increase the cacao production. This is due to the disruption of pests and the number of cacao farmers over land functions for fast growing plants. Processing cacao produced cacao waste and with the use of pyrolysis technology is able to cope with the accumulation of plantation waste. This combustion results in liquid smoke of cacao (cacao vinegar) into distillate, charcoal. This study used pyrolysis temperature between 100-500 °C. The aim of this research is to analyze the cocoa waste and the results are cellulose content 17,27%, lignin 52,02% and hemicellulose 19,56%. The results of GC-MS analysis for cacao vinegar of Distric Wajo are acetic acid, n butane, methyl ester, propanoic acid, butanoic acid, cyclopenanone, 2 methyl pyridine, acetyloxy 2 propanone, butyrolactone, tetrahydro 2 furan methanol, 2,3 dimethyl 2 cyclopentene 1 on and Mequinol. The water content of the charcoal of cacao shell from Wajo district is 3.42%. The analysis results of the bound carbon content of activated charcoal of cacao shell is 54.45%. The EDS analysis for cacao shell from Wajo district resulted in C: 61.12%, O: 36.65%, Si: 0.59%, P: 1.48% and Al: 0.17%. Utilization of cocoa shell waste using pyrolysis technology can reduce carbon emissions to the environment. So that the development of everything can continue and the sustainability of forest remain sustainable.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;

Variability and correlation of physical attributes of soils cultivated with cacao trees in two climate zones in Southern Bahia, Brazil

Cacao (Theobroma cacao) is a very important crop in Southern Bahia, Brazil, which needs good climate and soil conditions and management for great productivity. In this region, cacao is grown on a large number of soil types, and soil properties have great effects on its sustainability and production potentials. The aim of this study was to evaluate the variability of physical attributes of soils cultivated with cacao in two climate zones in Southern Bahia, Brazil, as well as to evaluate the correlation between these physical attributes. Eighty soil samples were evaluated from 20 cacao farms with cacao agroforestry systems, from the 0–0.1 and 0.1–0.3 m soil layers. The soil analyses comprised granulometry, soil bulk density, particle density, porosity (total, macro, and micro), gravimetric moisture, and soil resistance to penetration. The data were submitted to descriptive statistical analysis and correlation between variables. Most variables had normal distribution (p > 0.05) and high variability. In general, these soils had good physical conditions for the production of cacao, except for the high resistance to root penetration which can be limiting factor. The greatest differences in physical attributes of the soils were: gravimetric moisture, resistance to penetration, macroporosity, and sand content. The correlations between physical attributes of the soils varied according to the sampled layer and the climate zone. The resistance to penetration was not correlated with any of the determined physical attribute.

The differential influence of temperature on Phytophthora megakarya and Phytophthora palmivora pod lesion expansion, mycelia growth, gene expression, and metabolite profiles

Phytophthora megakarya and Phytophthora palmivora cause black pod rot of cacao. P. megakarya occurs in Africa while P. palmivora is distributed world-wide. P. palmivora has a higher temperature maximum (34 °C) than P. megakarya (30 °C). Factors contributing to temperature maxima in Phytophthora species have not been studied in detail. In culture, P. megakarya lost viability after 3 days at 32 °C while P. palmivora viability began decreasing after 3 days at 36 °C. When exposed to heat, genes encoding heat shock proteins and chaperones were most commonly induced in both species. Heat responsive genes in P. palmivora also tended to be induced at low temperatures (9 °C and 11 °C). In general, P. palmivora maintained higher metabolite pools than P. megakarya, although some temperature induced differences were recorded. When recovering from heat stress, P. megakarya produced a coralloid form of mycelia not previously observed in any Phytophthora species. P. megakarya's temperature range mimics the cacao production conditions in Africa and elevated seasonal field temperatures there are unlikely to persist long enough to eliminate P. megakarya although Phytophthora induced disease epidemiology may be influenced.

Application of Genome Wide Association and Genomic Prediction for Improvement of Cacao Productivity and Resistance to Black and Frosty Pod Diseases.

Chocolate is a highly valued and palatable confectionery product. Chocolate is primarily made from the processed seeds of the tree species Theobroma cacao. Cacao cultivation is highly relevant for small-holder farmers throughout the tropics, yet its productivity remains limited by low yields and widespread pathogens. A panel of 148 improved cacao clones was assembled based on productivity and disease resistance, and phenotypic single-tree replicated clonal evaluation was performed for 8 years. Using high-density markers, the diversity of clones was expressed relative to 10 known ancestral cacao populations, and significant effects of ancestry were observed in productivity and disease resistance. Genome-wide association (GWA) was performed, and six markers were significantly associated with frosty pod disease resistance. In addition, genomic selection was performed, and consistent with the observed extensive linkage disequilibrium, high predictive ability was observed at low marker densities for all traits. Finally, quantitative trait locus mapping and differential expression analysis of two cultivars with contrasting disease phenotypes were performed to identify genes underlying frosty pod disease resistance, identifying a significant quantitative trait locus and 35 differentially expressed genes using two independent differential expression analyses. These results indicate that in breeding populations of heterozygous and recently admixed individuals, mapping approaches can be used for low complexity traits like pod color cacao, or in other species single gene disease resistance, however genomic selection for quantitative traits remains highly effective relative to mapping. Our results can help guide the breeding process for sustainable improved cacao productivity.

WEAK LEVELS OF SOCIAL CAPITAL AS ONE OF THE CAUSES OF THE FALL OF MEXICAN CACAO PRODUCTION

AIM/BACKGROUNDOne of the major motives for dramatic decrease of cacao production is the impact of Moniliophthora roreri, a pathogenous fungus. The problem of Mexican cacao production however could be more complex than just a challenge related to chemical or biological elimination of the fungus. It is a problem of a social and demographic nature, related to cultural practices, age of producers, abandonment of the traditional production manners, which could be understood as a function of dynamics of social capital in the Mexican countryside. The study hence attempts to find a link between social capital and productivity of the producers in a cacao producing region in Central Tabasco, with the goal to illuminate possible strategies for revival of declining traditional sector of production.&#x0D; METHODS Data collection took place in February 2016 in municipality C-16 Gral. Emiliano Zapata, Cardenas, in Central Tabasco in South-eastern Mexico, where 101 semi-structured questionnaires with a combination of 50 principal questions entailing 230 subquestions which however include aksi monthly calendars.We compare the production of chosen variables products with four chosen Social Capital indicators, searching for a relationship using Mincer’s regression model through cross sections of data analysis with fixed effects within Ordinary Least Square (OLS) method.&#x0D; RESULTSThe result point at rather a surprising result of a negligent importance of social capital and productivity of the cacao plantation. The hypothesis on a significant relationship between social capital associated with a producer and rentability of annual production of cacao per hectare cannot be confirmed. In other words, producers that show low level of social connectivity not necessarily have to show lower productivity per hectar, while the productivity is rather dependent on other factors.&#x0D; CONCLUSION The cacao belongs to most important agricultural crops worldwide, in recent decades facing increasing demand as well as falling production capacity. The dramatically fall of production of cacao in Mexican agriculture, where it was first domesticated, is becoming a serious concern for diversity of local production, as local producers are substituting cacao plantations with more rentable crops thus giving away a rich genetic as well as agricultural legacy that could under adequate conditions provide a source of income for large region while maintaining the natural diversity. The paper comes to the conclusion that it is collective action and social capital led production set of practices that is crucial for the re-installment and prosperity of the plantations, rather than a single motive such as the recent invasion of Moniliophthora roreri fungus.