Contribution to the Identification of Toxic Vascular Plants by the Epidermis of the Epicarp of Fleshy Fruits

Objective: The main objectives of the present work were: 1) to securely identify the fleshy fruits of a relevant number of species of toxic vascular plants by their epicarp features; 2) to draw attention to the potential of fruit micromorphology in the identification of poisonous plants and in plant taxonomy.

Methods: The epicarp sections were bleached with sodium hypochlorite, mounted on microscopy slides and observed through light microscopy. Micrometry was done for a number of characters.

Results: A histological description for the epicarp epidermis of each taxon was provided. A dichotomous key that differentiates all the species studied was produced.

Conclusion: The qualitative and quantitative microcharacters allowed, in all cases the identification at the species level. A dichotomous key to the taxa was constructed. As the different genera and species were easily separated, the usefulness of the microcharacters in the identification of toxic plants and in plant taxonomy is supported by the present work. We believe that an increase in the number of characters and the use of new microscopy techniques (e.g. scanning electron microscopy and confocal microscopy) will most probably allow the identification of a greater number of poisonous species in the future.