Use of plants and aspects of local knowledge in the rural community of Brejal, Rio de Janeiro, Brazil

Abstract Rural communities have repertoires of knowledge associated with the use of plants related to various social and biological aspects. The objective of this study was to identify the diversity of use of food and medicinal plants by the Brejal rural community in Rio de Janeiro state, Brazil. Ethnobotanical data was obtained using the snowball technique and semi-structured interviews with 22 farmers. Species diversity and use-value indices were calculated. Relationships among the numbers of plants cited, interviewee age, gender, and working time in agriculture were investigated. We identified a high diversity index, comprising 185 species belonging to 53 botanical families, notably Asteraceae, Lamiaceae, and Brassicaceae. The greatest use-values were associated with exotic species. Leaves were the plant structures most utilized, and infusions the predominant method of preparation. The prescriptions most commonly cited related to illnesses of the digestive system. Men and women did not differ in terms of the numbers of species cited. We found no correlations between the ages of the interviewees and their working time in agriculture. The uniformity of the number of citations demonstrates the shared knowledge throughout the community, covering a high diversity of plants, uses, indications and preparations.