Identificação de plantas tóxicas e medidas de controle: um guia técnico para produtores rurais

Abstract

This research originates from a detailed diagnostic study conducted during the initial phase of a matrix project. The central theme of this project was a regional issue concerning the perception and management of toxic plants by rural producers in the Guajará-Mirim region of Rondônia (RO), Brazil. The first phase, a field study involving the application of a questionnaire to 88 farmers, revealed a concerning scenario. Although producers recognized the most notorious toxic species, such as Palicourea marcgravii (known locally as "erva-de-rato"), there was a low adherence to preventive control practices. This management gap is exacerbated by the fact that 60% of the interviewees admitted to being unable to correctly identify plants toxic to cattle. This deficiency translates into direct economic losses, with 33% of respondents reporting animal mortality due to poisoning. In light of these findings, and in direct response to the identified demand—wherein a significant 75% of producers reported the need for training—this dissertation constitutes the second stage of the project. The primary objective of this work is, therefore, to translate scientific knowledge into a practical tool that can effectively bridge the identified information gap. To this end, the research focused on developing a technical booklet, an educational and user-friendly reference material designed to assist producers in the identification, management, and control of the most relevant toxic plants in their local context. To support the creation of this booklet, a systematic literature review was conducted. Its scope encompassed the main plant species cited as problematic during the field study, including Palicourea marcgravii, Pteridium aquilinum, Asclepias curassavica, Lantana camara, Psychotria ipecacuanha, Ricinus communis, Sorocea bonplandii, and Hybanthus calceolaria. For each species, the booklet addresses the following essential topics: scientific and common names, toxic principles, toxic parts of the plant, most susceptible animal species (cattle, horses, sheep, and goats), main clinical signs per species, botanical characteristics for field identification, and effective control strategies. The consolidation of this booklet aims to equip the producer with applicable knowledge, fostering autonomy in pasture management and contributing to the reduction of losses in the local livestock industry.