Introducción. La composición arbórea asociada al cacao criollo y la que se desarrolla en los sistemas productivos de cacao, es diferente. Esta información es importante para adoptar futuras estrategias en programas de conservación y mejoramiento. Objetivo. Contribuir al conocimiento sobre la composición arbórea de especies asociadas al cacao criollo en México. Materiales y métodos. Los datos analizados en este estudio incluyeron variables de la estructura horizontal y vertical, además de la diversidad de especies arbóreas asociadas al cacao en diferentes condiciones. Este estudio se realizó durante mayo a septiembre del 2018, en parcelas donde se encontraron árboles de cacao criollo en su hábitat natural de la selva Lacandona y en plantaciones de cacao en tres localidades del Soconusco, en Chiapas, México. En las mismas se contabilizaron y clasificaron taxonómicamente las especies arbóreas. Resultados. Asociadas al cacao criollo en la selva Lacandona se registraron veintiún especies, que se agruparon en diecinueve géneros y trece familias, cuya abundancia, riqueza y densidad fue mayor que la registrada en sistemas productivos de cacao en la región del Soconusco, lo que contribuyó a una diferencia entre ambos ecosistemas con solo dos especies compartidas. Conclusión. La abundancia, riqueza y densidad de especies arbóreas asociadas al cacao criollo fue mayor que la registrada en los sistemas de producción, con disimilitud en sus condiciones. Se registraron diferencias en la localización del cultivo del cacao dentro de la estructura vertical de ambos escenarios estudiados.

Objective: To evaluate the effect of hydrogen peroxide, potassium sorbate, sodium bicarbonate, and chitosan on mycelial growth and in vitro germination of Colletotrichum sp., to be used for future management of anthracnose disease in postharvest cv. Ataulfo mango fruit. Design/Methodology/Approach: The effectiveness of the treatments was evaluated using the poisoned culture method. The evaluated concentrations of hydrogen peroxide and potassium sorbate were 1.0, 0.8, 0.6, 0.4, 0.2, 0.16, 0.12, 0.08, and 0.04 %; sodium bicarbonate, 1.0, 0.8, 0.6, 0.4 and 0.2 %; and chitosan, 2.5, 2.0, 1.5, 1.0 and 0.5 %. A 6-day disk of Colletotrichum sp. mycelial growth was placed in each poisoned culture medium. The inhibition of mycelial growth and the germination of Colletotrichum sp. conidia were evaluated. The experimental design was completely randomized with five repetitions for mycelial growth and four for conidium germination. The results were analyzed using the Kruskal-Wallis test and the comparison of average ranges. The CE50 and CE95 of each product was estimated using Probit analysis with the results of mycelial growth inhibition. Results: The mycelial growth inhibition (100%) of the Colletotrichum sp. strain was reached starting at concentrations of 0.16, 0.2, 1.0, and 2.5% for hydrogen peroxide, potassium sorbate, sodium bicarbonate, and chitosan, respectively. The inhibition of conidium germination was only observed in treatments with hydrogen peroxide and potassium sorbate. The CE50 and CE95 for hydrogen peroxide was 0.1 and 0.12%; for potassium sorbate, 0.10 and 0.19%; for sodium bicarbonate, 0.16 and 0.88%; and for chitosan, 1.20 and 2.18%. Findings/Conclusions: The evaluated treatments represent an effective and viable ecological alternative for the control of Colletotrichum sp., causal agent of anthracnosis in mango fruit.

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Introduction: The organoleptic qualities of aromatic species and their derived products are directly related to some characteristics of flavor, color and nutritional value and depend largely on their genetic origin and content of secondary metabolites. Objective: the antioxidant activity of different genotypes of Theobroma spp. from Mexico was evaluated in order to distinguish promising qualities for genetic improvement, and to differentiate phylogenetic traits, considering biochemical variables. Methods: the amount of phenols, flavonoids and antioxidant activity was determined by ABTS and DDPH, in addition to the content of anthocyanins, theobromine and caffeine in four species of Theobroma L., and 50 genotypes derived from T. cacao. The results were analyzed using an analysis of variance, means test, principal component analysis and cladistic analysis. Results: there are highly significant differences between genotypes. The phenol content ranged from 7.5-85 mg g-1; flavonoids 6.57-69.6 mg g-1, antioxidant activity by ABTS of 17.3-86.1 and by DDPH of 40.0-53.3; anthocyanin content of 0.01-3, caffeine of 1.8-6.7-and theobromine of 2.9-9.8 mg g-1. Principal component and cladistic analysis helped explain the variation found and distinguish evolutionary characters and phylogenetic brotherhoods. The variation in content of phenols, flavonoids, antioxidant activity, anthocyanins, theobromine and caffeine was mainly due to the degree of domestication, while for the group of genotypes derived from T. cacao (forastero, trinitario and criollo) it was the origin of the seeds. Conclusions: the degree of domestication influences the content of phenols and antioxidant capacity. The results suggest that the evaluated variables can help to form criteria for genetic improvement in the complex derived from T. cacao oriented to the selection of higher phenol content and greater antioxidant activity.