Melaleuca Essential Oil (Melaleuca alternifolia cheel) in the Control of Beans Diseases

Abstract

Bean cultivation is vital to the global food and economy, especially in Brazil. Facing challenges from diseases that affect production, it is crucial to seek new strategies to maintain productivity and sustainability. Melaleuca alternifolia, known as the tea tree due to its medicinal properties, has little explored potential in controlling diseases in bean plants. The objective of this work was to evaluate the effectiveness of tea tree essential oil in controlling diseases in bean cultivation. In vitro tests were carried out to evaluate bacterial growth, at concentrations of (0.0%, 0.05%, 0.1%, 0.5%, 1% and 2%). And antibiogram with the bacteria Xanthomonas axonopodis pv. phaseoli, in different concentrations (0.0%, 0.05%, 0.1%, 0.5%, 1%, 2% and 3%). For the fungus Pseudocercospora griseola, sporulation tests were carried out, using direct and indirect methods, at concentrations of (0.0%, 0.05%, 0.1%, 0.5%, 1%, 2%, and 3%). Furthermore, for the fungus Colletotrichum lindemuthianum, mycelial growth tests were carried out with the same concentrations. The experiments took place in vivo, with a completely randomized statistical design, involving five replications per treatment and concentrations varying from (0.0%, 0.05%, 0.1%, 0.5%, 1% and 2%). Disease incidence was assessed using a diagrammatic scale, disease severity, Area under the Disease Progress Curve (AACPD) and Area under the Incidence Progress Curve (AACPI). Melaleuca Essential Oil (EO) inhibited the development of fungi and bacteria in in vitro tests starting at 0.5%. In vivo, Melaleuca Essential Oil (EO) showed a significant reduction in the incidence and severity of the disease from 0.5% in both fungi and bacteria. Melaleuca EO can be an effective alternative for disease control in bean cultivation.