Myrcia lundiana Kiaersk native populations have different essential oil composition and antifungal activity against Lasiodiplodia theobromae

• High chemical diversity was observed among Myrcia lundiana plants.
• Three chemical groups were formed from the constituents of the essential oils.
• There is high correlation between bioactive compounds from M. lundiana..
• The essential oil of M. lundiana showed fungicidal activity.

Myrcia lundiana Kiaersk (Myrtaceae) is a medicinal and aromatic shrub or small tree up to 6 m high, without studies of chemical diversity and its use to control plant pathogens. The objectives of this study were to characterize the chemical diversity of the essential oil from leaves of M. lundiana plants collected in the state of Sergipe, and to evaluate the antifungal potential of one representative plant of each chemical group against Lasiodiplodia theobromae. Essential oils of 23 plants were obtained by hydrodistillation and analyzed by GC/MS-FID. Twenty four compounds were identified in the essential oil of M. lundiana plants. Chemical diversity was observed among plants, which were distributed within chemical clusters. Three clusters were formed by cluster analysis. Cluster I, consisting of 10 plants, was characterized by presenting nerolic acid (24.44–43.97%) and 1,8-cineole (10.53–33.75%) as the major compounds. Cluster II, consisting of 4 plants, presented neral (9.74–24.25%) and geranial (13.71–32.64%) as the major compounds; Cluster III, consisting of 9 plants, presented isopulegol (24.23–41.06%) and iso-isopulegol (11.42–5.26%) as the major compounds. The essential oils of the representing plants of M. lundiana, clusters I, II and III, provided mycelial growth inhibition of L. theobromae in all tested concentrations, reaching 100.0% mycelial growth inhibition in the concentration of 0.5 μL mL−1 (Cluster II), after 96 h of incubation.