Abstract This paper investigates the perception of river dwellers in the Brazilian Amazon region about factors that influence the transmission of Traditional Ecological Knowledge (TEK) regarding medicinal plants. Semi-structured interviews were conducted with 43 residents of Vila Franca community (Pará, Brazil). The data were analyzed using the methodological strategy of the Discourse of the Collective Subject. The determining factors in the transmission of TEK were found to be: illness, family coexistence, and necessity, which were represented in the discourses as the most important factors for the acquisition of TEK. In the community context, the locally developed Natural Remedies Project, the beneficial effects of natural remedies, and the lack of resources to purchase allopathic medicines were cited as collaborative factors in the maintenance of TEK. Finally, the most significant determining factors in the decrease or loss of transmission of TEK found in the interviews were: lack of commitment, disbelief, and the valorization of allopathic medicines. A complex network of interactions between the villagers and their natural environment affects the transmission of TEK about medicinal plants. However, we found that the perpetuation of TEK is being threatened by various socio-economic and cultural factors.

Em virtude da importância do saber popular na utilização de plantas medicinais e da contribuição desse saber na preservação da flora medicinal, o trabalho atual tem o objetivo de resgatar e sistematizar o conhecimento popular de espécies medicinais e sua relação com usos terapêuticos, em Rosário de Limeira, MG. Os dados foram coletados entre janeiro e março de 2007. Quinze informantes foram entrevistados sobre seus conhecimentos das espécies medicinais, residentes nas comunidades rurais e nos bairros do município. A pesquisa revelou o uso de 66 espécies pertencentes a 33 famílias (Asteraceae com o maior número de espécies, seguido por Lamiaceae, Rutaceae e Bignoniaceae) usadas no tratamento de várias patologias. Das espécies medicinais citadas, 44,3% crescem espontaneamente e 55,7% são cultivadas. A principal parte vegetal usada na preparação dos fitoterápicos é a folha e a preparação mais comum é a infusão. As espécies mais usadas são: Baccharis trimera, Mentha sp., Plantago major, Chenopodium ambrosioides e Symphytum officinale.

In order to evaluate the popular knowledge on the use of medicinal plants and the contribution in the preservation of medicinal flora, the present work aims to rescue and organize such knowledge on medicinal species and its relation with therapeutic uses, in the city of Rosario de Limeira, MG. Data were collected January to March, 2007. Fifteen informants, all resident in urban and agricultural communities, were asked about their knowledge on medicinal plants. The current survey revealed the use of 66 species belonging to 33 families (Asteraceae with the major number of species, followed by Lamiaceae, Rutaceae, and Bignoniaceae) used in the treatment of various diseases. 44,3% of them grow spontaneously and 55,7% are cultivated. The main vegetal part used in the preparation of the phytotherapy was the leaf, and the most common preparation was the infusion. The most used species were: Baccharis trimera, Mentha sp., Plantago major, Chenopodium ambrosioides and Symphytum officinale.