Potencial do óleo de andiroba (Carapa guianensis) como controle de sigatoka-amarela: ação antifúngica sobre Pseudocercospora sp.

Abstract

Banana cultivation in the state of Amazonas represents an agricultural activity of high socioeconomic relevance and constitutes an essential source of food and income for thousands of rural families. In 2024, for example, banana production in Amazonas reached 173.1 thousand tons, generating a gross value of R$ 512.3 million—a significant component of the state’s total agricultural production value, which amounted to R$ 3.1 billion. Moreover, banana farming ensures subsistence and income for approximately 9.8 thousand rural producers in the state. However, banana cultivation in Amazonas presents certain disadvantages, as it is affected by environmental conditions that favor the development of phytopathogens. Among these problems, Yellow Sigatoka has caused severe losses. This disease is caused by the fungus Pseudocercospora sp. (anamorph Pseudocercospora fijiensis), with its anamorphic form described as P. fijiensis Deighton. Current control of this pathogen relies on the intensive use of agrochemicals, which increases production costs, contaminates the environment, harms human health, hinders exportation, and may also lead to the development of resistant phytopathogen populations. To achieve a control strategy that is less harmful to the environment and human health, alternative methods that are less costly and safer have been sought. The Amazon region harbors one of the world’s greatest biodiversities, including a substantial number of essential oils and plant extracts that are traditionally used to treat fungal infections. Among these species, andiroba stands out. Thus, the objective of this study was to evaluate the in vitro antimicrobial activity of andiroba oil on the mycelial growth of Pseudocercospora sp. For the inhibition assay, oil concentrations of 5, 10, 15, and 20% were incorporated into Potato-Dextrose-Agar (PDA) culture medium. PDA without andiroba oil served as the control treatment. The results demonstrated that andiroba oil exhibits in vitro antifungal activity against Pseudocercospora sp. at all tested concentrations, with the most significant difference relative to the control observed at the 5% concentration. These findings indicate that andiroba oil presents promising antifungal effects. However, the underlying mechanisms involved in its interference with Yellow Sigatoka virulence, as well as its chemical constituents and analytical approaches for phytopathogens, still require further investigation.