Variability and antifungal activity of volatile compounds from Aniba rosaeodora Ducke, harvested from Central Amazonia in two different seasons

Finding new applications for the essential oils (EOs) of the branches and leaves of Aniba species represents a valuable strategy for the adoption of correct management of the crown and to help make Aniba plantations economically valuable. We report here the antifungal activity of the EO from Aniba rosaeodora Ducke against plant pathogenic fungi. The present study investigated the chemical variability and antifungal effect of EO from A. rosaeodora harvested during the wet and dry seasons in the Amazon region. The volatile content obtained from the aerial parts by hydro-distillation was analyzed for its chemical composition by gas chromatography-mass spectrometry (GC-MS). Furthermore, a broth and agar dilution method was used to determine the antifungal activity against phytopathogens. Quantitative and qualitative variations in composition among the EOs were detected. Linalool was a major component in the oil of leaves and branches from both periods. Quantification using an external standard showed a higher concentration of linalool in the wet season (74.4 ± 3.9% in leaves and 81.8 ± 5.7% in branches) than in the dry season (47.5 ± 2.2 in leaves and 49.2 ± 1.6% in branches). The EOs were toxic to all phytopathogens analyzed, displaying superior inhibitory activity toward Colletotrichum guaranicola, with inhibition zone diameters ranging from 15.2 ± 1.2 to 21.3 ± 1.7 mm and IC50 values of 0.578 to 2.094 μL mL−1. Interestingly, the EOs collected during the wet season were effective in reducing the vegetative growth of phytopathogens, providing evidence for the involvement of linalool in the inhibitory effect.