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Anthracnose of litchi fruits was characterized by internal and external brown circular lesions with well-defined margins on the pericarp, but not on the aril or seed. Colletotrichum sp., Pestalotiopsis sp., Fusarium sp., and Lasiodiplodia sp. were isolated from symptomatic fruit pericarp samples of cultivars Mauritius and Brewster in 2008-2010 cycles. Colletotrichum sp. (51%) and Pestalotiopsis sp. (17%) were isolated more frequently from symptomatic fruit pericarp samples of cultivar Mauritius in 2009. Colletotrichum sp. was isolated on PDA (39%) and in semi-selective medium (59%) from symptomatic Mauritius fruit pericarp samples in 2010, and from asymptomatic pericarp Brewster samples in 2009 (32%) and 2010 (21%) on PDA and 10% in semiselective medium; however it was not isolated from asymptomatic Mauritius pericarp in neither of the two harvesting years. Only Colletotrichum sp., reproduced the disease in the laboratory (17 out of 20 inoculated fruits) and in the field (19 out of 20 inoculated fruits). The fungus was morphologically and molecularly identified as Colletotrichum gloeosporioides Penz. [ABSTRACT FROM AUTHOR]

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 antioxi-dant 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 varia-tion 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. [ABSTRACT FROM AUTHOR]