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The study of plant–microbe interactions is a rapidly growing research field, with increasing attention to the role of seed-borne microbial endophytes in protecting the plant during its development from abiotic and biotic stresses. Recent evidence suggests that seed microbiota is crucial in establishing the plant microbial community, affecting its composition and structure, and influencing plant physiology and ecology. For Theobroma cacao L., the diversity and composition of vertically transmitted microbes have yet to be addressed in detail. We explored the composition and diversity of seed-borne endophytes in cacao pods of commercial genotypes (ICS95, IMC67), recently liberated genotypes from AGROSAVIA (TCS01, TCS19), and landraces from Tumaco (Colombia) (AC9, ROS1, ROS2), to evaluate microbial vertical transmission and establishment in various tissues during plant development. We observed a higher abundance of Pseudomonas and Pantoea genera in the landraces and AGROSAVIA genotypes, while the commercial genotypes presented a higher number of bacteria species but in low abundance. In addition, all the genotypes and plant tissues showed a high percentage of fungi of the genus Penicillium. These results indicate that domestication in cacao has increased bacterial endophyte diversity but has reduced their abundance. We isolated some of these seed-borne endophytes to evaluate their potential as growth promoters and found that Bacillus, Pantoea, and Pseudomonas strains presented high production of indole acetic acid and ACC deaminase activity. Our results suggest that cacao domestication could lead to the loss of essential bacteria for seedling establishment and development. This study improves our understanding of the relationship and interaction between perennial plants and seed-borne microbiota. [ABSTRACT FROM AUTHOR]

In Southeast Asia (SEA) fastidious fungi of the Ceratobasidium genus are associated with proliferation of sprouts and vascular necrosis in cacao and cassava, crops that were introduced from the tropical Americas to this region. Here, we report the isolation and in vitro culture of a Ceratobasidium sp. isolated from cassava with symptoms of witches' broom disease (CWBD), a devastating disease of this crop in SEA. The genome characterization using a hybrid assembly strategy identifies the fungus as an isolate of the species C. theobromae, the causal agent of vascular streak dieback of cacao in SEA. Both fungi have a genome size > 31 Mb (G+C content 49%), share > 98% nucleotide identity of the Internal Transcribed Spacer (ITS) and > 94% in genes used for species-level identification. Using RNAscope® we traced the pathogen and confirmed its irregular distribution in the xylem and epidermis along the cassava stem, which explains the obtention of healthy planting material from symptom-free parts of a diseased plant. These results are essential for understanding the epidemiology of CWBD, as a basis for disease management including measures to prevent further spread and minimize the risk of introducing C. theobromae via long-distance movement of cassava materials to Africa and the Americas. [ABSTRACT FROM AUTHOR]

The physicochemical and biochemical changes during the fermentation of four clones and two native varieties of Theobroma cacao L. were studied. Fermentation was performed in traditional wood cubes. During fermentation, the cotyledon pH decreased, and the temperature increased to more than 10 °C above the ambient temperature (47 °C). The fermentation index (FI) increased in the clones C1, C4, C8, C9, and Guayaquil (G) to close to one at 120 h of fermentation. For the FI of the cocoa Criollo (Cr), a value of 2.5 was proposed according to the spectrophotometric scan performance. The total polyphenol content increased in all the samples from 21 (C8) to 70 (Cr) % in a comparison of the TPC at T0 and T120, respectively. The total flavonoid content increased from 16 (C8) to 51% in Guayaquil (G) during the fermentation period. In the case of the methylxanthines, such as theobromine and caffeine, both quantities decreased. The theobromine content decreased in all the samples from 6 (G) to 31% (C8). The caffeine content decreased in all the samples from 3% in Cr to 25% in C1 and G after fermentation. The antioxidant capability did not change after 120 h of fermentation, and the amount of methylxanthines did not affect the antioxidant potential of the fermented cocoa. The FTIR scan of the fat-free cocoa showed significant differences between the unfermented and fermented beans, and several peaks assigned to carbohydrates and proteins decreased. [ABSTRACT FROM AUTHOR]

Introduction: Wound healing of tooth extraction is associated with fibroblasts that are produced during the proliferation phase. The use of herbal extracts is currently being investigated by researchers, as it allows avoiding the side effects of synthetic drugs. Cocoa pod husk extract is one of the alternative herbal ingredients that contains active compounds which have antibacterial, antioxidant and anti-inflammatory effects. This study aims to analyze the effects of the cocoa pod husk extract (Theobroma cacao L.) on wound gap closure and collagen density on tooth extraction socket in rats. Materials and methods: Twenty-four Wistar rats with first molar removed in the left mandibular region divided into three groups: negative control group (CMC-Na gel), positive control group (Alvolgyl), and treatment group (100 mg/ ml cocoa pod husk extract gel). Samples were sacrificed on days 7 and 14 after teeth extraction and gel application. The wound gap closure and collagen density was analized using Masson's Trichrome staining, and determined by image raster software and Adobe Photoshop CS 6.0 software. Data was analyzed using One Way ANOVA and post hoc LSD. Results: The treatment group administered with cocoa pod husk 100 mg/ml extract gel showed a higher average value compared to control groups. There were significant differences in wound gap closure (p<0.05), but the increasing collagen density was not significantly different on 14th day (p>0.05). Conclusion: Cocoa pod husk extract (Theobroma cacao L.) potential increasing wound gap closure and collagen density on rat molar tooth extraction socket. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the stability of cacao clone production by analyzing the dynamics of pod production over time. It investigates correlations in multi-year production levels and explores how genetics influence both intra-annual and inter-annual temporal production dynamics of total and healthy pods. To address these questions, data were analysed from a clonal cacao trial conducted over a period of 18 years in Costa Rica. Longitudinal data analysis provided a clearer understanding of the link between yields over successive years. The best-fit model proved to be the ante-dependence model. This model indicated that the correlation between two successive years was relatively stable, and the correlation between years decreased as the interval between years increased. These correlations are also higher as the age of the trees increases. The clones differ more in terms of their production of healthy pods than total pod production. Four dynamic patterns, considering both intra- and inter-annual production, were identified, revealing differences in production timing and distinct peaks for each class. Inter-annual variability analysis revealed differences in healthy pod production among classes, with some displaying more sustainable production dynamics over 18 years. Intra-annual variability analysis showed significant variation in production periods among clones, with different production distributions throughout the year allowing selection of escape and or resistant clones. The study emphasized the importance of genetics in sustainable cacao production, with potential implications for clonal selection. It was suggested to combine clones of different classes to mitigate risks and spread harvests, emphasizing that resilience is a crucial criterion in cacao breeding programs to effectively meet new challenges. Further research is recommended to explore the influence of various environmental factors and facilitate more efficient selection in perennial crops, with the aim of selecting more resilient clones, a particularly important objective in the context of climate change. [ABSTRACT FROM AUTHOR]

This research study compares two methods of cellulose extraction from Theobroma cacao L. (CMT) clone Federación Arauquita 5 (FEAR 5) husks. Method 1 (Lubis) is an alkaline treatment with heating that uses sodium hydroxide and whitening with sodium hypochlorite. In the second method, a soxhlet extraction is conducted for a period of six hours, followed by an alkaline-acidic treatment. Physicochemical and thermographic analyzes are conducted to identify characteristics specific to the extraction method. The results show that the highest mass cellulose yield is obtained by the modified Lubis method 1 with 27.09%. It is concluded that the cellulose obtained can be produced and used to develop biotechnological products, contributing to the circular economy and the sustainable development of cocoa in the Department of Risaralda, Colombia. [ABSTRACT FROM AUTHOR]

Microbial community control is crucial for maintaining homeostasis of the gut–liver axis in metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we show that supplementation with a mixture of Mexican foodstuffs (MexMix)—Opuntia ficus indica (nopal), Theobroma cacao (cocoa) and Acheta domesticus (crickets)—enriches several beneficial taxa in MASLD mice and overweight/obese humans. Thus, MexMix induces an important prebiotic effect. In mice, a restoration of intestinal health was observed due to the increased short-chain fatty acids (SCFAs) and intestinal crypt depth, Ocln and Cldn1 expression, and decreased Il6 and Tnfa expression. MexMix significantly reduced steatosis in the mice's liver and modified the expression of 1668 genes. By PCR, we corroborated a Tnfa and Pparg decrease, and a Cat and Sod increase. In addition, MexMix increased the hepatic NRF2 nuclear translocation and miRNA-34a, miRNA-103, and miRNA-33 decline. In overweight/obese humans, MexMix improved the body image satisfaction and reduced the fat intake. These findings indicate that this new food formulation has potential as a therapeutic approach to treat conditions associated with excessive consumption of fats and sugars. [ABSTRACT FROM AUTHOR]

Witches' broom disease (WBD) affects cocoa trees (Theobroma cacao L.) and is caused by the fungus Moniliophthora perniciosa that grows in the apoplast in its biotrophic phase and later progresses into the tissues, causing serious losses in the production of cocoa beans. Therefore, the apoplast of T. cacao can provide important defense responses during the interaction with M. perniciosa. In this work, the protein profile of the apoplast of the T. cacao genotypes Catongo, susceptible to WBD, and CCN-51, resistant one, was evaluated. The leaves of T. cacao were collected from asymptomatic plants grown in a greenhouse (GH) and from green witches' brooms grown under field (FD) conditions for extraction of apoplastic washing fluid (AWF). AWF was used in proteomic and enzymatic analysis. A total of 14 proteins were identified in Catongo GH and six in Catongo FD, with two proteins being common, one up-accumulated, and one down-accumulated. In CCN-51, 19 proteins were identified in the GH condition and 13 in FD, with seven proteins being common, one up-accumulated, and six down-accumulated. Most proteins are related to defense and stress in both genotypes, with emphasis on pathogenesis-related proteins (PR): PR-2 (β-1,3-glucanases), PR-3 and PR-4 (chitinases), PR-5 (thaumatine), PR-9 (peroxidases), and PR-14 (lipid transfer proteins). Furthermore, proteins from microorganisms were detected in the AWF. The enzymatic activities of PR-3 showed a significant increase (p < 0.05) in Catongo GH and PR-2 activity (p < 0.01) in CCN-51 FD. The protein profile of the T. cacao apoplastome offers insight into the defense dynamics that occur in the interaction with the fungus M. perniciosa and offers new insights in exploring future WBD control strategies. [ABSTRACT FROM AUTHOR]

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

The growth, enzyme activity, and nutritional value of Theobroma cacao L. are strongly affected under hypoxic conditions and by the toxicity of iron (Fe). It is a challenge to mitigate the stress caused by excessive levels of Fe under flooding in cocoa trees. This study evaluated the physiological response of two cocoa genotypes to different Fe concentrations and hypoxic conditions. The plants were cultivated under three Fe concentrations (44.5, 133.5, and 400.5 lmol L-1 FeSO4) and two hydroponic cultivation conditions, one with an oxygenated nutrient solution and the other solution without oxygenation (hypoxia). Growth characteristics, enzyme activity, and nutritional balance were evaluated at 116 days after planting. An increased guaiacol peroxidase activity and higher phenolic compound contents of genotype TSH 1188 were observed at the Fe concentration of 400.5 lmol L-1 under hypoxia. The genotype SIAL 70 was also recorded increased with rising Fe concentrations, even without aeration. Regardless of the hypoxic conditions, the calcium content of both genotypes decreased with increasing Fe concentrations in the nutrient solution, while the Zn concentration of genotype TSH 1188 increased, regardless of the hypoxic nutrient solution, and that of genotype SIAL 70 decreased under hypoxic conditions. The genotypes respond differently to Fe excess and hypoxia, indicating distinct tolerance mechanisms for each stress type. In general, the tolerance of genotype TSH 1188 and SIAL 70 to the combination of Fe excess and hypoxia, respectively, was high and moderate, suggesting that the two genotypes have different mechanisms to support these stress conditions. [ABSTRACT FROM AUTHOR]

Fine flavor cocoa (FFC) is known for its unique flavor and aroma characteristics, which vary by region. However, a comprehensive overview of the common sensory attributes used to describe FFC beans and chocolate is lacking. Therefore, a systematic review was conducted to analyze existing literature and identify the most commonly used sensory attributes to describe FFC beans and chocolate. A systematic search of the Web of Science and Scopus databases was conducted in May 2023, and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were followed to ensure transparency and reproducibility. This review summarizes the origins of cocoa and explores their unique flavor profiles, encompassing caramel, fruity, floral, malty, nutty, and spicy notes. Although some origins may exhibit similar unique flavors, they are often described using more specific terms. Another main finding is that although differences in sensory attributes are anticipated at each production stage, discrepancies also arise between liquor and chocolate. Interestingly, fine chocolate as the final product does not consistently retain the distinctive flavors found in the liquor. These findings emphasize the need for precise descriptors in sensory evaluation to capture flavor profiles of each origin. As such, the exploration of attributes from bean to bar holds the potential to empower FFC farmers and chocolate producers to effectively maintain quality control. [ABSTRACT FROM AUTHOR]

Cocoa beans (Theobroma cacao L.) can be used for craft chocolate production, which arouses consumer interest due to their perceived better quality. This study aimed to evaluate the chemical profile of 80% artisanal chocolate samples produced with cocoa beans subjected to different maturation conditions. In the first maturation process, beans were matured under no-oxygen conditions, and in the second, the toasted beans were matured in oak barrels. The volatile compounds of the chocolate samples were extracted by the solid-phase microextraction method in headspace mode and analyzed by gas chromatography/mass spectrometer. The non-volatile compounds were extracted with methanol and analyzed through paper spray mass spectrometry. Overall, 35 volatile compounds belonging to different chemical classes (acids, alcohols, aldehydes, ketones, esters, and pyrazines) were identified, such as propanoic acid and butane-2,3-diol. In addition, 37 non-volatile compounds, such as procyanidin A pentoside and soyasaponin B, were listed. Tannins, flavonoids, and phenylpropanoids were the main chemical classes observed, varying between the two samples analyzed. Therefore, it was possible to verify that maturation conditions affected the metabolomic profile of the 80% artisanal chocolate samples, being able to influence the sensory characteristics and bioactive compounds profile. Given these results, the sensory evaluation of these chocolates is suggested as the next step. [ABSTRACT FROM AUTHOR]

DNA methylation is an important epigenetic mark that plays a crucial role in regulating various biological processes and adaptation to environmental conditions in both plants and animals. At present, there are no reports on the systematic analysis of the DNA-(cytosine-5) methyltransferase (C5-MTase) and demethylase (dMTase) gene families from the cacao (Theobroma cacao) genome. In this study, a comprehensive bioinformatic analysis identified the presence of seven C5-MTases (TcC5-MTases) and three dMTases (TcdMTases) in cacao. According to the sequence similarity, and conserved motif and domain architecture, TcC5-MTases were phylogenetically classified into METHYLTRANSFERASE 1 (TcMET1), CHROMOMETHYLASE (TcCMT1-3), DOMAINS REARRANGED METHYLASE (TcDRM1/2, TcDRM3), and de novo DNA METHYLTRANSFERASE 2 (TcDNMT2), and TcdMTases were classified into DEMETER (TcDME), REPRESSOR OF SILENCING 1 (TcROS1, also known as DEMETER-LIKE 1 (TcDML1)), and TcDML3 subfamilies. These genes were distributed randomly on six chromosomes. Moreover, most of the TcC5-MTases and TcdMTases were putatively localized in the nucleus, except TcDRM1/2 and TcDRM3, which were found in chloroplasts. Further analysis of cis-acting regulatory elements (CREs) in the promoter regions TcC5-MTase and TcdMTase genes inferred the presence of multiple CREs, especially stress-responsive, light-responsive, and hormone-responsive elements. Additionally, the analysis of protein–protein interaction networks revealed interactions among TcC5-MTases and with other proteins in T. cacao, such as S-adenosyl-L-homocysteine hydrolase and histone deacetylases, suggesting potential crosstalk among DNA methylation, the methionine cycle, and histone deacetylation. These interactions provide valuable insights into the complexity of regulating plant methylation levels. Collectively, the findings of this study provide a framework for further functional characterization of these genes and unravel the epigenetic mechanisms underlying growth and development, as well as adaptations to stress conditions in cacao. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study explored the impact of Leucothyreus femoratus, a previously unreported folivorous pest in cacao cultivation, on cacao tree survival, development, and yield. The study was conducted in an experimental cacao plot in the Colombian plains, it featured 20 cacao genotypes in an agroforestry system, with plantain and Mexican sunflower providing temporary shade, and yopo offering permanent shade. RESULTS: We found an infestation rate of 2.9 ± 0.3 adult beetles per cacao tree. L. femoratus larvae were discovered in association with the roots of all plants within the agroforestry arrangement; however, yopo and plantain exhibited the highest incidence of root‐feeding larvae among these associated plants. Interestingly, male and female L. femoratus displayed distinct leaf consumption patterns in the laboratory, with females consuming more foliage relative to their body weight. Moreover, field observations highlighted the detrimental impact of L. femoratus herbivory on cacao tree survival and growth, leading to leaf skeletonization, reduced plant height, and stem diameter. Trees with over 50% leaf consumption suffered more than 20% mortality. Additionally, herbivory negatively affected cacao yield, correlating higher leaf surface damage with a decrease in harvested pods. The study also identified varying antixenotic resistance in different cacao genotypes, with some consistently displaying resistance while others showed variable levels during tree establishment and production stages. CONCLUSION: This research underscores the significant role of L. femoratus as a cacao pest, emphasizing its adverse effects on cacao tree survival, development, and yield. Consequently, implementing effective control measures is vital for ensuring sustainable cacao cultivation. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The Baracoa region, eastern Cuba, hosts around 80 % of the country cacao (Theobroma cacao L.) plantations. Cacao plants in farms are diverse in origin and propagation, with grafted and hybrid plants being the more common ones. Less frequent are plants from cuttings, TSH progeny, and traditional Cuban cacao. A national cacao gene bank is also present in Baracoa, with 282 accessions either prospected in Cuba or introduced from other countries. A breeding program associated with the gene bank started in the 1990s based on agro-morphological descriptors. The genetic diversity of cacao resources in Baracoa has been poorly described, except for traditional Cuban cacao, affecting the proper development of the breeding program and the cacao planting policies in the region. To assess the population structure and genetic diversity of cacao resources in Baracoa region, we genotyped plants from both cacao gene bank (CG) and cacao farms (CF) applying a new ddRADseq protocol for cacao. After data processing, two SNPs datasets containing 11,425 and 6,481 high-quality SNPs were generated with 238 CG and 135 CF plants, respectively. SNPs were unevenly distributed along the 10 cacao chromosomes and laid mainly in noncoding regions of the genome. Population structure analysis with these SNP datasets identified seven and four genetic groups in CG and CF samples, respectively. Clustering using UPGMA and principal component analysis mostly agree with population structure results. Amelonado was the predominant cacao ancestry, accounting for 49.22 % (CG) and 57.73 % (CF) of the total. Criollo, Contamana, Iquitos, and Nanay ancestries were detected in both CG and CF samples, while Nacional and Marañon backgrounds were only identified in CG. Genetic differentiation among CG (FST ranging from 0.071 to 0.407) was higher than among CF genetic groups (FST: 0.093-0.282). Genetic diversity parameters showed similar values for CG and CF samples. The CG and CF genetic groups with the lowest genetic diversity parameters had the highest proportion of Amelonado ancestry. These results should contribute to reinforcing the ongoing breeding program and updating the planting policies on cacao farms, with an impact on the social and economic life of the region. [ABSTRACT FROM AUTHOR]

Cacao (Theobroma cacoa L.) is an important tropical fruit tree used in chocolate production. Among the biotic problems interfering with fruit production, phytopathogenic fungi stand out. During a visit to cocoa production areas in the municipality of Medicilândia, Pará, Brazil (Amazon region), we observed cocoa fruits with dark lesions and greyish‐white cottony mycelia growth. In order to determine the aetiological agent's identity, we extracted DNA and amplified part of the TEF‐1α and RBP2 genes and compared them with sequences in GenBank using the BLASTn tool. Based on molecular results and phylogenetic analysis, the isolates were identified as Calonectria hawksworthii. Inoculations in cacao fruits showed symptoms after 6 days and were similar to those collected in the field, confirming the postulates. This study is the first report of Ca. hawksworthii causing cocoa bean rot worldwide. [ABSTRACT FROM AUTHOR]

High concentrations of toxic cadmium (Cd) in soils are problematic as the element accumulates in food crops such as rice and cacao. A mitigation strategy to minimise Cd accumulation is to enhance the competitive uptake of plant-essential metals. Theobroma cacao seedlings were grown hydroponically with added Cd. Eight different treatments were used, which included/excluded hydroponic or foliar zinc (Zn) and/or iron (Fe) for the final growth period. Analyses of Cd concentrations and natural stable isotope compositions by multiple collector ICP-MS were conducted. Cadmium uptake and translocation decreased when Fe was removed from the hydroponic solutions, while the application of foliar Zn-EDTA may enhance Cd translocation. No significant differences in isotope fractionation during uptake were found between treatments. Data from all treatments fit a single Cd isotope fractionation model associated with sequestration (seq) of isotopically light Cd in roots and unidirectional mobilisation (mob) of isotopically heavier Cd to the leaves (ε114Cdseq-mob = −0.13‰). This result is in excellent agreement with data from an investigation of 19 genetically diverse cacao clones. The different Cd dynamics exhibited by the clones and seen in response to different Fe availability may be linked to similar physiological processes, such as the regulation of specific transporter proteins. [ABSTRACT FROM AUTHOR]

In plants, serpins are a superfamily of serine and cysteine protease inhibitors involved in stress and defense mechanisms, with potential for controlling agricultural pests, making them important biotechnological tools. The objective of this study was to characterize a serpin from Theobroma cacao, called TcSERPIN, to identify its endogenous targets and determine its function and biotechnological potential. TcSERPIN has 390 amino acid residues and shows conservation of the main active site, RCL. Cis-elements related to light, stress, hormones, anaerobic induction, cell cycle regulation and defense have been identified in the gene's regulatory region. TcSERPIN transcripts are accumulated in different tissues of Theobroma cacao. Furthermore, in plants infected with Moniliophtora perniciosa and Phytophthora palmivora, the expression of TcSERPIN was positively regulated. The protein spectrum, rTcSERPIN, reveals a typical β-sheet pattern and is thermostable at pH 8, but loses its structure with temperature increases above 66°C at pH 7. At the molar ratios of 0.65 and 0.49, rTcSERPIN inhibited 55 and 28% of the activity of papain from Carica papaya and trypsin from Sus scrofa, respectively. The protease trap containing immobilized rTcSERPIN captured endogenous defense proteins from cocoa extracts that are related to metabolic pathways, stress and defense. The evaluation of the biotechnological potential against geohelminth larvae showed that rTcSERPIN and rTcCYS4 (Theobroma cacao cystatin 4) reduced the movement of larvae after 24 hours. The results of this work show that TcSERPIN has ideal biochemical characteristics for biotechnological applications, as well as potential for studies of resistance to phytopathogens of agricultural crops. [ABSTRACT FROM AUTHOR]

This study investigates the application of random regression models for analyzing multi-harvest data in cacao breeding. The aim was to understand the genetic dynamics over ten harvest years and select high-performing genotypes. The trial was conducted in Ouro Preto D'Oeste, Rondônia, Brazilian Amazon. Twenty biparental cacao crosses were evaluated over ten years using random regression models. Models with different polynomial degrees and covariance structures for the residual effects were compared, and the best model was determined using Akaike Information Criterion. We also compared the genetic gains after selecting using three criteria: breeding values, persistence, and area under genotypic trajectories. The best random regression models differed between traits. Genotype-by-harvest interactions were observed, emphasizing the temporal variability in genotype performance. Genetic correlations across harvests illustrated the dynamic nature of genetic expression. Accuracy and heritability fluctuated over successive harvests, emphasizing the complexity of genotype performance prediction. Non-linear genotypic trajectories revealed the presence of unique genetic attributes associated with each trait, with number of healthy fruits showing a tendency towards standardization and dry bean weight displaying a more complex pattern. Consistency in selecting genotypes based on number of healthy fruits highlights reliable selection. Conversely, the variability in choosing top genotypes for dry bean weight underscores the need for cautious selection strategies, as it is a more complex trait to optimize. Despite these insights, future research should consider specific environmental conditions, management practices, and the integration of genomic information for a more comprehensive understanding of genetic dynamics in cacao breeding. [ABSTRACT FROM AUTHOR]

Cocoa (Theobroma cacao L.), has its origin in the Amazon and is usually grown under the shade of trees and or in full sun exposure. This variability in light conditions makes physiological responses different between cocoa cultivars. In the coming decades, an inevitable increase in global temperature is expected. By 2050, it is estimated that in the Latin American tropical region these increases will lead to reductions in precipitation greater than 10%, that is, we will have drier environments, which will undoubtedly affect cocoa cultivation. There is uncertainty in the possible effects of changes in temperature on cocoa due to the lack of information and the few cultivars that have been evaluated. The information collected in this review serves as a basis for understanding the responses of cocoa to light and temperature conditions and it is undeniable that more research is required to achieve a greater understanding of the complexities of climate changes and their effects on cocoa production. One aspect that stands out is a focus on research that must be carried out in field conditions. [ABSTRACT FROM AUTHOR]

To date, in vitro somatic embryogenesis is the only option for the mass vegetative propagation of cocoa. The somatic embryogenesis of Indonesian cocoa clones SUL1 and SUL2 was investigated, focusing on primary and cyclic secondary embryogenesis. The study showed that staminode explants were more effective than petal explants in generating primary somatic embryos (SEs), especially when cultured in liquid medium containing 2 mg/L 2,4-D and 0.25 mg/L kinetin, with the staminodes of SUL2 producing a significant number of globular SEs. In contrast, SUL1 showed limited SE production. The study also demonstrated that fragmenting cotyledons and hypocotyls of the SEs of SUL2 and culturing them on an induction medium supplemented with 2,4,5-T and proline resulted in a high yield of secondary SEs. This cyclic embryogenesis process, in which the SEs remained attached to the maternal tissue, facilitated continuous SE production and development. The addition of proline was found to improve the quality of SEs, leading to higher production of well-organized, milky SEs with a better-defined meristematic structure. These results suggest a promising protocol to produce SEs from cocoa, with implications for plant transformation and gene editing applications. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is one of the essential mineral micronutrients most demanded by cacao. Cadmium (Cd) is highly toxic to plants and other living beings. There are indications that Mn can interact with Cd and mitigate its toxicity. The objective of this study was to evaluate the action of Mn on the toxic effect of Cd in young plants of the CCN 51 cacao genotype, subjected to different doses of Mn, Cd, and Mn+Cd in soil, through physiological, biochemical, molecular, and micromorphological and ultrastructural changes. High soil Mn doses favored the maintenance and performance of adequate photosynthetic processes in cacao. However, high doses of Cd and Mn+Cd in soil promoted damage to photosynthesis, alterations in oxidative metabolism, and the uptake, transport, and accumulation of Cd in roots and leaves. In addition, high Cd concentrations in roots and leaf tissues caused irreversible damage to the cell ultrastructure, compromising cell function and leading to programmed cell death. However, there was a mitigation of Cd toxicity when cacao was grown in soils with low Cd doses and in the presence of Mn. Thus, damage to the root and leaf tissues of cacao caused by Cd uptake from contaminated soils can be attenuated or mitigated by the presence of high Mn doses in soil. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine Cd accumulation under water-deficit conditions by young cacao plants. The study was conducted under greenhouse conditions. Two full-sib families (IMC67 × PA121 and SCA6 × PA121), obtained through controlled crosses, and an open pollinated half-sib seedling family of IMC67, widely used as rootstock in Colombia, were employed. Plants were grown in Cd-contaminated soil (0.356 mg kg−1) without external sources of the metal. They were subjected to water deficit by suspending irrigation for consecutive periods of 19 and 27 days (D19 and D27), followed by rehydration. Water stress reduced leaf water potential (Ψleaf) with values from −1.51 to −2.09 MPa, with full-sib family SCA6 × PA121 being the most tolerant to water deficit. Cd concentration was influenced by biomass reduction (observed in IMC67 × PA121 and SCA6 × PA121) and transpiration rate (evident in IMC67) caused by water deficit. Full-sib progenies IMC67 × PA121 and SCA6 × PA121 accumulated more Cd in the plants than open pollinated IMC67, with higher Cd accumulation in leaves. The translocation factor (TF) revealed that the aboveground organs of the progenies were enriched with Cd (TF > 4). Water deficit increased Cd translocation from roots to leaves in IMC67 × PA121 and IMC 67, while there were no significant changes in SCA6 × PA121. Full-sib family SCA6 × PA121 stood out as the most promising progenies due to their water-stress tolerance and Cd accumulation stability. This study introduces a discussion about the influence of water stress on Cd accumulation in Theobroma cacao. [ABSTRACT FROM AUTHOR]

Ecuador is one of the leading producers of fine aroma cocoa worldwide, involving around 100,000 producer families. On the American continent, the largest producer is Brazil, with 18%, followed by Ecuador and Colombia, and it is estimated that more than 20 million people depend directly on this crop. Moniliophthora roreri, the causal agent of frost pot rot, has been a cause of great concern due to the production losses it has caused, which in 2022 amounted to 80% in different cocoa-producing provinces of Ecuador and worldwide losses of 30% performance they are estimates. This study aimed to determine the biological control potential of microcapsules made with Trichoderma spp spore solution against M. roreri. The In vitro evaluation of the microcapsules did not show significant results in the percentage of inhibition, and this was not the case in the direct evaluation on the farm, where the severity in the 15-day-old fruits showed 0% external and internal affectation with the use of microcapsules in its liquid presentation. Additionally, the evolution of the microcapsules in 28-day-old fruits was observed in severity from 1 to 25% with intercalated applications. Beneficial fungi were applied first, followed by pathogens; though, when the pathogen was applied first, and then the beneficial fungus, the increased severity of external and internal disease was 26-75% and 80-100%, respectively. In conclusion, using microcapsules based on Trichoderma strains at the early ages of the fruits generates protection against M. roreri throughout the vegetative development of the fruit. [ABSTRACT FROM AUTHOR]

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The basidiomycete Moniliophthora roreri causes frosty pod rot of cacao (Theobroma cacao) in the western hemisphere. Moniliophthora roreri is considered asexual and haploid throughout its hemibiotrophic life cycle. To understand the processes driving genome modification, using long-read sequencing technology, we sequenced and assembled 5 high-quality M. roreri genomes out of a collection of 99 isolates collected throughout the pathogen's range. We obtained chromosome-scale assemblies composed of 11 scaffolds. We used short-read technology to sequence the genomes of 22 similarly chosen isolates. Alignments among the 5 reference assemblies revealed inversions, translocations, and duplications between and within scaffolds. Isolates at the front of the pathogens' expanding range tend to share lineage-specific structural variants, as confirmed by short-read sequencing. We identified, for the first time, 3 new mating type A locus alleles (5 in total) and 1 new potential mating type B locus allele (3 in total). Currently, only 2 mating type combinations, A1B1 and A2B2, are known to exist outside of Colombia. A systematic survey of the M. roreri transcriptome across 2 isolates identified an expanded candidate effector pool and provided evidence that effector candidate genes unique to the Moniliophthoras are preferentially expressed during the biotrophic phase of disease. Notably, M. roreri isolates in Costa Rica carry a chromosome segment duplication that has doubled the associated gene complement and includes secreted proteins and candidate effectors. Clonal reproduction of the haploid M. roreri genome has allowed lineages with unique genome structures and compositions to dominate as it expands its range, displaying a significant founder effect. [ABSTRACT FROM AUTHOR]

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accumulation of high cadmium (Cd) levels in cacao beans (Theobroma cacao) generate several commercial and health issues. We hypothesized that cacao phenotypic and genotypic diversity could provide new insights to decrease Cd accumulation in cacao beans. Nine cacao rootstock genotypes were evaluated for up to 90 days under 0, 6, and 12 (mg·kg−1) of CdCl2 exposure and Cd content and plant growth dynamics were measured in leaves, stems, and roots. Data revealed that all cacao genotypes studied here were highly tolerant to Cd, since they presented tolerance index ≥ 60%. In shoots, EET61 and PA46 presented the higher (~270 mg·kg DW−1) and lower (~20 mg·kg DW−1) Cd concentration, respectively. Accordingly, only the EET61 showed an increase in the shoot cadmium translocation factor over the 90 days of exposure. However, when analyzing cadmium allocation to different organs based on total plant dry mass production, none of the genotypes maintained high Cd compartmentalization into roots, since P46, which was the genotype with the highest allocation of Cd to the roots, presented only 20% of total cadmium per plant in this plant organ and 80% allocated into the shoots, under Cd 12 (mg·kg−1) and after 90 days of exposure. Thus, genotypic/phenotypic variability in cacao rootstocks may provide valuable strategies for maximizing the reduction in Cd content in shoots. In this sense, IMC67 and PA46 were the ones that stood out in the present study. [ABSTRACT FROM AUTHOR]

Trees in cacao Agroforestry systems (AFS) may present a high potential for cadmium (Cd) phytoextraction, helping to reduce Cd in cacao (Theobroma cacao L.) plants grown in contaminated soils. To assess this potential, four forest fine-woody species commonly found in cacao high-productive sites in Colombia (Tabebuia rosea, Terminalia superba, Albizia guachapele, and Cariniana pyriformis) were exposed to contrasting CdCl2 contamination levels (0, 6, and 12 ppm) on a hydroponic medium. Growth dynamics, tolerance index (TI), and Cd concentration and allocation in leaves, stems, and roots were evaluated for up to 90 days after initial exposure. T. superba, A. guachapele, and C. pyriformis were classified as moderately tolerant (TI > 0.6), and T. rosea was considered a sensitive species (TI < 0.35) under 12 ppm Cd contamination. Despite showing a high stem Cd concentration, C. pyriformis also showed the lowest relative growth rate. Among the evaluated forest species, A. guachapele exhibited the highest Cd accumulation capacity per plant (2.02 mg plant−1) but also exhibited a higher Cd allocation to leaves (4%) and a strong decrease in leaf and stem dry mass after 90 days of exposure (~75% and 50% respectively, compared to control treatments). Taking together all the favorable features exhibited by T. superba as compared to other CAFS tree species and recognized phytoextractor tree species in the literature, such as Cd hyperaccumulation, high tolerance index, low Cd concentration in leaves, and high Cd allocation to the stem (harvestable as wood), this species is considered to have a high potential for cadmium phytoextraction in cocoa agroforestry systems. [ABSTRACT FROM AUTHOR]

The fungus Moniliophthora perniciosa secretes protein effectors that manipulate the physiology of the host plant, but few effectors of this fungus have had their functions confirmed. We performed functional characterization of a promising candidate effector of M. perniciosa. The inoculation of rBASIDIN at 4 µmol L−1 in the mesophyll of leaflets of Solanum lycopersicum caused symptoms of shriveling within 6 h without the presence of necrosis. However, when sprayed on the plant at a concentration of 11 µmol L−1, it caused wilting symptoms only 2 h after application, followed by necrosis and cell death at 48 h. rBASIDIN applied to Theobroma cacao leaves at the same concentration caused milder symptoms. rBASIDIN caused hydrogen peroxide production in leaf tissue, damaging the leaf membrane and negatively affecting the photosynthetic rate of Solanum lycopersicum plants. Phylogenetic analysis indicated that BASIDIN has orthologs in other phytopathogenic basidiomycetes. Analysis of the transcripts revealed that BASIDIN and its orthologs are expressed in different fungal species, suggesting that this protein is differentially regulated in these basidiomycetes. Therefore, the results of applying BASIDIN allow the inference that it is an effector of the fungus M. perniciosa, with a strong potential to interfere in the defense system of the host plant. [ABSTRACT FROM AUTHOR]

Cocoa (Theobroma cacao L.) is one of the most important economic crops worldwide. The propagation of elite varieties of cocoa has been achieved through somatic embryogenesis, but still one of the main limitations is the low rates of embryo formation, which is a genotypedependent trait. Manipulation of transcription factors (TFs) such as BABY BOOM (BBM) promotes the transition of cocoa somatic cells from the vegetative to the embryonic state. This work validated the use of clonal cocoa leaves cv. IMC-67 to induce somatic embryogenesis, overcoming their recalcitrant limitation with the help of the introduction of TF-BBM from Arabidopsis thaliana (AtBBM). The vectors were constructed by the Gateway system using the donor vector pENTR/D-TOPO and the expression vector pk7WG2. The overexpression vector pk7WG2:AtBBM was obtained, allowing successful transformation into Agrobacterium tumefaciens GV3101. The AtBBM gene was characterized (1755 base pairs), and its expression was observed in the formation of embryogenic calluses in cocoa leaves. Overexpression of AtBBM allowed the obtainment of a 92% response in the formation of embryogenic callus in cocoa leaves with Agrobacterium-mediated vacuum infiltration and overexpression of the pk7WG2:AtBBM vector. This high transformation efficiency reached with the insertion of the overexpression vector provides validation of transient response of the TF AtBBM in the formation of embryogenic calluses in cocoa leaves of the IMC-67 clone. Through this methodology, it is possible to continue with studies of gene overexpression, insertion, silencing, and gene editing in Peruvian cocoa. [ABSTRACT FROM AUTHOR]

In Mexico, cacao production is endangered by pathogenic fungi, such as Phytophthora spp. and Moniliophthora rorei, that cause black pod rot and moniliasis, respectively. In this study the biocontrol agent Paenibacillus sp. NMA1017 was tested in cacao fields against the previous diseases. The treatments applied were shade management, inoculation of the bacterial strain with or without an adherent, and use of chemical control. The statistical analysis showed that the incidence of black pod rot in tagged cacao trees diminished when the bacterium was applied (reduction of 44.24 to 19.11%). The same result was observed with moniliasis when the pods were tagged (reduction of 66.6 to 27%). The use of Paenibacillus sp. NMA1017 with an integrated management might be a solution to cacao diseases and to having a sustainable production of cacao in Mexico. [ABSTRACT FROM AUTHOR]

Moniliasis caused by the fungus Moniliophthora roreri is one of the most destructive cacao diseases in tropical America. In 2021, the presence of the pathogen was confirmed in cacao plantations in Brazil. This is the first proteomic study of the M. roreri protein profile of ungerminated spores and mycelium compared by 2D SDS‐PAGE (Two‐dimensional gel electrophoresis) associated with mass spectrometry. A total of 446 spots were detected on ungerminated spores gels and 402 spots on M. roreri mycelial gels. A total of 29 proteins were identified from the ungerminated spores, 21 of them were exclusive, and 53 were identified in the mycelium, 16 of them were exclusive. Most of the identified proteins at both development stages were categorized as being involved in metabolic processes, reduction/oxidation processes, and protein synthesis and folding. The interaction networks observed expand the known interactions of these proteins, resulting in eight functional clusters for proteins identified in ungerminated spores and seven clusters for mycelial proteins. In addition, a biological model of ungerminated spores and mycelium with cell location of proteins was constructed. The results contribute to a better understanding of the metabolic mechanisms of M. roreri during dormancy and vegetative development, which can support future studies for strategies to control moniliasis. [ABSTRACT FROM AUTHOR]

• Genetic barcoding is a promising tool to identify cryptic cacao pollinators. • Dipteran pollinator diversity is higher than previously assumed. • Genetic barcoding can be used to trace individuals to their breeding habitats. • Banana pseudostems, understory weeds, decaying cacao pod husks, and cacao leaf litter are potential breeding habitats for cacao pollinators. Determining the main pollinators and the factors that control their abundance is a prerequisite for improving the production of many crops, including the globally important cash crop cacao (Theobroma cacao L.). Yet, the identity and the breeding habitats of cacao pollinators remain controversial since they are very difficult to identify morphologically due to their small size. It is known that tiny midges are involved in cacao pollination, but their diversity and ecology remain obscure. Here, we combined the collection of flower visitors, the use of emergence traps, and DNA barcoding to assess the diversity of dipteran cacao flower visitors and link them to five candidate breeding habitats in an agroforestry system in central Nicaragua. We detected 59 lineages of dipteran flower visitors, including Cecidomyiidae, Ceratopogonidae, Chironomidae, and Sciaridae, suggesting that dipteran cacao pollinator diversity may be much higher than previously assumed. Five lineages could be genetically traced back to specific breeding habitats. We conclude that the presented approach can be a promising tool to reliably delineate potential pollinator species and their breeding habitats, which can inform management strategies to promote cacao pollination. [Display omitted] [ABSTRACT FROM AUTHOR]

The zinc/iron-regulated transporter-like protein (ZIP) gene family first identified in plants is highly distributed in the plant kingdom. This family has previously been reported to transport several essential and non-essential cationic elements, including those toxic to many economically important crops such as cacao (Theobroma cacao L.). In this article, we present a detailed study on physicochemical properties, evolution, duplication, gene structure, promoter region and TcZIP family three-dimensional protein structure. A total of 11 TcZIP genes have been identified to encode proteins from 309 to 435 aa, with localization in the plasma membrane and chloroplast, containing 6-9 putative domains (TM). Interspecies phylogenetic analysis subdivided the ZIP proteins into four groups. Segmental duplication events significantly contributed to the expansion of TcZIP genes. These genes underwent high pressure of purifying selection. The three-dimensional structure of the proteins showed that a helix conformations are predominant with several pocket sites, containing the metal binding site, with the residues leucine (LEU), alanine (ALA), glycine (GLY), serine (SER), lysine (LYS) and histidine (HIS) the most predicted. Regarding the analysis of the protein-protein interaction and enrichment of the gene ontology, four biological processes were assigned, the most important being the cation transport. These new discoveries expand the knowledge about the function, evolution, protein structures and interaction of ZIP family proteins in cacao and contribute to develop cacao genotypes enriched with important mineral nutrients as well as genotypes that bioaccumulate or exclude toxic metals. [ABSTRACT FROM AUTHOR]

Introduction: Theobroma cacao, the cocoa tree, is a target for pathogens, such as fungi from the genera Phytophthora, Moniliophthora, Colletotrichum, Ceratocystis, among others. Some cacao pathogens are restricted to specific regions of the world, such as the Cacao swollen shoot virus (CSSV) in West African countries, while others are expanding geographically, such as Moniliophthora roreri in the Americas. M. roreri is one of the most threatening cacao pathogens since it directly attacks the cacao pods driving a significant reduction in production, and therefore economic losses. Despite its importance, the knowledge about the microenvironment of this pathogen and the cocoa pods is still poorly characterized. Methods: Herein we performed RNA sequencing of spores in differential stages of culture in a medium supplemented with cacao pod extract and mycelium collected of the susceptible variety ICT 7121 naturally infected by the pathogen to evaluate the diversity and transcriptional activity of microorganisms associated with the in vitro sporulation of M. roreri. Results: Our data revealed a great variety of fungi and bacteria associated with M. roreri, with an exceptional diversity of individuals from the genus Trichoderma sp. Interestingly, the dynamics of microorganisms from different kingdoms varied proportionally, suggesting they are somehow affected by M. roreri culture time. We also identified three sequences similar to viral genomes from the Narnaviridae family, posteriorly confirmed by phylogenetic analysis as members of the genus Narnavirus. Screening of M. roreri public datasets indicated the virus sequences circulating in samples from Ecuador, suggesting a wide spread of these elements. Of note, we did not identify traces of the viral sequences in the M. roreri genome or DNA sequencing, restricting the possibility of these sequences representing endogenized elements. Discussion: To the best of our knowledge, this is the first report of viruses infecting the fungus of the genus Moniliophthora and only the third description of viruses that are able to parasite elements from the Marasmiaceae family. [ABSTRACT FROM AUTHOR]

Cocoa (Theobroma cacao L.) is an important crop in Peru. International regulations require products derived from cocoa to be free of heavy metals (HMs), such as cadmium. Arbuscular mycorrhizae (AM) contribute to reduced HM content in the plant, preventing its accumulation in the fruit and facilitating the rhizodeposition of HMs through glomalin-related soil proteins (GRSP). We studied the presence of mycorrhizal symbiosis in cocoa plants and cadmium in three plantations in San Martín, Peru. The maximum Cd content detected in soils was 1.09 (mg/kg), an amount below the tolerable limit for agricultural soil (≥1.4 mg/kg). Cocoa roots showed 68–86% active mycorrhizal colonization; agronomic management did not cause differences between plantations. Levels of GRSP were between 7.67 (GRSP-EE) and 13.75 (GRSP-T) mg protein g soil−1. Morphological and molecular analysis of Glomeromycota fungi showed the presence of families Claroideoglomeraceae, Paraglomeraceae, Gigasporaceae, Glomeraceae, Acaulosporaceae, Archaeosporaceae, and Diversisporaceae. Our results show the presence of arbuscular mycorrhizal symbiosis in cocoa plantations and suggest that T. cacao may phytostabilize HM in its rhizosphere through the production of GRSP. The presence of mycorrhizal symbiosis indicates the potential for the preparation of biofertilizers for cocoa since the production of GRSP is promissory for the biostabilization of soil HMs. [ABSTRACT FROM AUTHOR]

Frosty pod rot, caused by Moniliophthora roreri, is the most damaging disease of cacao in Latin America and, to better comprehend its epidemiology, we must understand its dissemination and proliferation. However, we do not know how M. roreri spores loads fluctuate in time and space due to the lack of a reliable technique to quantify M. roreri spores in the fields. Therefore, we developed a method that relies on spore traps and qPCR to detect and quantify M. roreri spore loads. This study demonstrated that the qPCR protocol can detect down to 0.025 ng of M. roreri DNA and quantify between 0.006 ng and 60 ng. Moreover, it demonstrated that qPCR protocol can detect and quantify DNA extracted from spore suspension and spore traps containing at least 2.9 × 104 M. roreri spores. However, the variability of the estimates for spore samples was high. Finally, we described a spore-trap device designed to carry spore traps in the field. The qPCR protocol and spore-trap device here developed will help in the understanding of the M. roreri dissemination patterns since they can be used to assess the environmental loads of M. roreri spore in cacao fields. [ABSTRACT FROM AUTHOR]

In Mexico, Theobroma cacao is affected by the black pod rot (BPR) caused by Phytophthora capsici. Currently, an epidemiological study of this disease is lacking. The objective was to determine the influence of climate, fruit set and the incidence of cacao frosty pod rot (Moniliophthora roreri) on the epidemic intensity of BPR in five locations in southeastern Mexico. The temporal structure of BPR epidemics was analyzed and the correlation of absolute change of BPR incidence with temperature, relative humidity (RH), precipitation, and fruiting flows was studied. The possible competition between P. capcisi and M. roreri was also analyzed correlatively. The epidemics had a duration of 15 to 25 weeks restricted to September - February with 6 to 24% final incidence (Yf ). The curves were best fitted to the Gompertz model (r = 0.059 - 0.123, R2 0.97 - 0.99) with an exponential phase in October corresponding with the highest rainfall. BPR was positively associated with RH greater than 90%, precipitation, temperature periods lower than 19.9, and 20 - 26.9 °C, and with fruiting intensity. P. capcisi had less parasitic fitness than M. roreri, which induced earlier epidemics, with greater duration and intensity. The characterization of BPR as a polycyclic epidemic justifies management strategies aimed at reducing the secondary inoculum. [ABSTRACT FROM AUTHOR]

GRAS genes exist widely and play vital roles in various physiological processes in plants. In this study, to identify Theobroma cacao (T. cacao) GRAS genes involved in environmental stress and phytohormones, we conducted a genome-wide analysis of the GRAS gene family in T. cacao. A total of 46 GRAS genes of T. cacao were identified. Chromosomal distribution analysis showed that all the TcGRAS genes were evenly distributed on ten chromosomes. Phylogenetic relationships revealed that GRAS proteins could be divided into twelve subfamilies (HAM: 6, LISCL: 10, LAS: 1, SCL4/7: 1, SCR: 4, DLT: 1, SCL3: 3, DELLA: 4, SHR: 5, PAT1: 6, UN1: 1, UN2: 4). Of the T. cacao GRAS genes, all contained the GRAS domain or GRAS superfamily domain. Subcellular localization analysis predicted that TcGRAS proteins were located in the nucleus, chloroplast, and endomembrane system. Gene duplication analysis showed that there were two pairs of tandem repeats and six pairs of fragment duplications, which may account for the rapid expansion in T. cacao. In addition, we also predicted the physicochemical properties and cis-acting elements. The analysis of GO annotation predicted that the TcGRAS genes were involved in many biological processes. This study highlights the evolution, diversity, and characterization of the GRAS genes in T. cacao and provides the first comprehensive analysis of this gene family in the cacao genome. [ABSTRACT FROM AUTHOR]

The objective of this study was to improve cacao (Theobroma cacao) production through its association with a woody species, such as Ricinodendron heudelotii, in western Côte d'Ivoire. To do this, a design of two transects (10 m and 20 m) was installed around the species in 5 localities (Buyo, Duekoué, Guéyo, San-Pedro, and Soubré). The diameter at the breast height of the tree, the height, the number of fruits, the above biomass, and its carbon stock were measured. Results showed morphological variability of R. heudelotii according to the localities. The presence of the species within cacao trees reduces the rate of pod rot, stabilizes the rate of pods eaten away, and increases the biomass production and the carbon storage of cacao trees. The distance between the two species had no impact on the vigor and the yield of cacao trees. However, cacao density in the 10 m line was reduced compared to that of the 20 m. Therefore, the integration of R. heudelotii into cacao agroforestry systems could improve cacao production. That is why the reduction of cacao density, as well as the use of more suitable varieties of cacao, should be considered for the sustainability of this system. [ABSTRACT FROM AUTHOR]

The regulation established by the European Union regarding cadmium (Cd) is hindering the global trade of cocoa and cocoa products. The objective was to investigate the variation in Cd uptake and accumulation in plants of five genotypes of 'fine-aroma' cocoa grown under hydroponic conditions with the addition of 20 µmol of CdCl2. Our results showed that Cd uptake, translocation, and accumulation at leaf and root tissue levels varied significantly among genotypes. Cd accumulation in the root system was manifested after 24 h of cultivation exposed to Cd, with concentrations ranging from 72.40 mg kg-1 and 112.24 mg kg-1. Polynomial analysis showed a clear relationship between Cd accumulation and plant exposure time. It was observed the INDES 38 genotype is the most promising for future breeding programs because despite high Cd accumulation in its roots (156.75 ± 0.90 mg kg-1), the amount of metal transferred to leaves was low. [ABSTRACT FROM AUTHOR]

Copyright of Agroalimentaria is the property of Alejandro Antonio Gutierrez Socorro and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cocoa (Theobroma cacao L.) is widely cultivated in tropical countries. The cocoa beans are a popular ingredient of confectionery. Cocoa beans contain various chemicals that contribute to their bioactivity and nutritional properties. There has been increasing interest in developing cocoa beans for "healthy" food products. Cocoa beans have special combination of nutrients such as lipids, carbohydrates, proteins and other compounds of biological activities. The bioactive phytochemicals include methylxanthines, polyphenols, biogenic amines, melanoidins, isoprostanoids and oxalates. These phytochemicals of cocoa are related to various in vivo and in vitro biological activities such as antioxidation, anti-cancer, anti-microbial, anti-inflammation, anti-diabetes, cardiovascular protection, physical improvement, anti-photoaging, anti-depression and blood glucose regulation. The potential of bioactive compounds in cocoa remains to be maximized for food and nutritional applications. The current processing technology promotes the degradation of beneficial bioactive compounds, while maximizing the flavors and its precursors. It is not optimized for the utilization of cocoa beans for "healthy" product formulations. Modifications of the current processing line and non-conventional processing are needed to better preserve and utilize the beneficial bioactive compounds in cocoa beans. [ABSTRACT FROM AUTHOR]

In the south of Bahia state, a large part of the native Atlantic Forest areas has been modified for the cultivation of cocoa (Theobroma cacao). These crops are cultivated under the shade of the canopy of native trees, a system locally known as the "cabruca" agroforestry system. This study aimed to evaluate the relationship of Odonata assemblages (adults and larvae) in cocoa farming areas and to identify the relationships of these species with local and spatial environmental variables of the monitored sites. Altogether, adult and larvae were sampled at 22 sites. Physical and physicochemical water variables were recorded for each site. A total of 1336 dragonflies were collected, of which 20 were Zygoptera species and 30 were adult Anisoptera representatives. The different life stages were related to environmental variables such as conductivity, watercourse channel width, and dissolved oxygen. The space predictors were also associated with the assemblages, mainly for adults. The present study identified that cabruca areas maintain a great diversity of dragonflies, including species that are considered to be forest specialists and more sensitive to landscape changes. The characteristics of this cropping system are considered to be favorable for the conservation of the biodiversity of the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Recent surveys conducted on Amazonian cocoa trees in their home range are a unique opportunity to assess the aromas, diversity and potential of the Ecuadorian Amazon to create new aromatic cocoa varieties. Our results reveal informations about the diversity and genesis of aromas in Ecuadorian fine cocoa. The great aromatic diversity could enrich cocoa flavour selection programmes and provide Amazonian populations with new income linked to aromatic varieties, which could lead to a 'grand cru' chocolate. Until now, breeding programmes have been mainly focused on improving characteristics for production, but in recent years cocoa quality has been increasingly examined to meet market expectations. Summary: Ecuador is known worldwide for its fine or flavour cocoa from the Nacional variety. Currently, farmers mainly grow the modern Nacional variety of cocoa trees (hybrids between the ancestral Nacional and Trinitario) while the ancestral Nacional variety tends to be neglected. In order to enlarge the genetic resources related to this ancestral variety, several surveys were carried out in its area of origin located in the South Ecuadorian Amazonia.The 202 trees resulting from these surveys were genotyped using GBS (Genotyping By Sequencing) markers and their dried‐fermented beans were characterised for both their aromatic volatile compounds and sensorial quality. A genome wide association study (GWAS) was carried out with the aim to study the genetic and biochemical bases of the aroma traits of this population and to better exploit them in breeding programmes.Some association areas and candidate genes related to spicy and woody aromas were found for the first time in Theobromacacao. Some association areas and candidate genes related to floral and fruity aromas common to other studies were identified.Our results support the hypothesis that aroma formation may be related to a defence reaction to biotic and abiotic stresses generated by the fermentation process. [ABSTRACT FROM AUTHOR]

The organic management of Theobroma cacao in agroforestry systems is a viable alternative, which is being applied in the Alborada Estate under the name of Mendis Organic Management (MOM) in honor of the researcher and owner of the experimental area. The MOM technology integrates a set of techniques according to the physiological cycle of the plant such as drastic annual pruning, application of compost, foliar biofertilizer, and the use of a variety of cocoa with high planting density. Therefore, the research evaluated the effect of MOM management on soil quality with cocoa plantations (varieties CCN-51 and CMP-15), under agroforestry system developed in the Alborada farm, Leoncio Prado province, Huanuco, Peru. A completely randomized design (CRD) was carried out, the treatments were cocoa areas: CCN-51 of 2x2 m and 10 years of installation (MOM1), CMP-15 of 2x2 m and 4 years (MOM2), CMP-15 of 2x1 m and 5 years (MOM3), CMP-15 of 3x2 m and 13 years (MOM4). Soil physical and chemical indicators were evaluated. All indicators showed significant differences between treatments, the principal component analysis (PCA) considered relevant the sand fraction, clay, OM, N, Ca2+, Mg2+, K+ and CEC, the modeling shows a negative impact in MOM2 and significantly positive in MOM4, regardless of the variety and planting density, observing significant increases for pH, OM, N, P, Ca2+, Ma2+ and CEC. The work shows the great potential of MOM management as a technological alternative to improve soil quality in cocoa plantations under agroforestry systems. [ABSTRACT FROM AUTHOR]

The inclusion of shade trees into cocoa (Theobroma cacao L.) systems can generate livelihood opportunities for smallholder farmers. Yet, there is the need to examine the ecological context within which shade trees, and their functional traits, have a positive impact on ecosystem services in cocoa systems. Here, we used a network of farms of similar aged hybrid cocoa, in a nested design consisting of agroforestry or monoculture management, on three initial soil quality levels (poor, moderate or good) in two agroecological zones (humid or sub-humid) to investigate whether shade tree functional traits are linked with soil-based and cocoa-based ecosystem services. Initial soil quality level was the main driver of differences in soil organic matter, soil N, soil C:N, soil total C, soil permanganate-oxidizable C, while agroecological zone largely explained differences in cocoa yield and aboveground C. The inclusion of shade trees increased soil macrofauna abundance and mass but decreased cocoa aboveground C compared to cocoa monoculture plots. Importantly, within agroforestry systems, shade tree leaf traits expressed as community weighted means of SLA, leaf N, and leaf dry matter content explained differences in soil-based and cocoa-based ecosystem services. These results show that agroforestry systems have the potential to enhance soil-based ecosystem services without notably decreasing cocoa yield. And a trait-based approach to describe shade tree diversity can advance our understanding and management of shade tree-ecosystem service relationships in cocoa agroforestry systems. • The ecological context within which shade tree traits have a positive impact is unclear. • Shade tree specific leaf area and leaf C:N vary with agroecological zone and soil quality level. • Initial soil quality level explains the largest variation in soil carbon and macrofauna variables. • Community-level shade tree traits predict soil-based and cocoa-based ecosystem services. [ABSTRACT FROM AUTHOR]

Fungi of the genus Ceratocystis are aggressive tree pathogens that cause serious diseases in several crops around the world. Ceratocystis wilt disease caused by C. cacaofunesta has been shown to be responsible for severe reductions in cacao production. In this study, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used in combination with chemometric analysis for monitoring volatile organic compounds (VOCs) released from C. cacaofunesta. Low-molecular-weight esters, alcohols, ketones, and sulphur compounds were identified in the liquid broth. Monitoring the volatile profile over five days of fungal growth revealed that the concentrations of alcohol and esters were inversely proportional. Acetate esters were responsible for the intense fruity aroma of the C. cacaofunesta culture produced within the first hours after fungal inoculation, which decreased over time, and are likely associated with the attraction of insect vectors to maintain the life cycle of the pathogen. PCA revealed that 3-methylbutyl acetate was the metabolite with the highest factor loading for the separation of the VOC samples after 4 h of fungal growth, whereas ethanol and 3-methylbutan-1-ol had the highest factor loadings after 96 and 120 h. 3-Methylbutan-1-ol is a phytotoxic compound that is likely associated with host cell death since C. cacaofunesta is a necrotrophic fungus. Fungal VOCs play important roles in natural habitats, regulating developmental processes and intra- and interkingdom interactions. This is the first report on the volatiles released by C. cacaofunesta. [ABSTRACT FROM AUTHOR]