Antifungal Activity of Heracleum platytaenium Essential Oil Against Fungi Causing Apple Scab and Monilia Disease

This study investigates the antifungal activity of the essential oil of Heracleum platytaenium Boiss., an endemic species in Türkiye, against the phytopathogenic fungi Monilinia spp. and Venturia inaequalis. The essential oil was obtained by hydrodistillation from the fruits collected at the full flowering stage. The antifungal effects of different concentrations (5 µL, 10 µL, 20 µL) of the essential oil were evaluated in vitro on Monilinia spp. and V. inaequalis isolates. Antifungal activity was determined based on the percentage inhibition of mycelial growth and statistical analyses. The results showed that the essential oil exhibited a dose-dependent inhibitory effect on both pathogens. The highest inhibition rates were recorded as 48.8% for Monilinia spp. and 46.6% for V. inaequalis. Differences in antifungal activity were observed depending on the extraction year, with the 2021 essential oil samples showing higher inhibition rates compared to those from 2022. The findings suggest that H. platytaenium essential oil has significant potential as a biopesticide and may serve as a natural control agent against phytopathogens. These results highlight the importance of plant-based antifungal agents in sustainable agricultural practices and offer new insights into alternatives to chemical fungicides.