Investigation of Fusarium spp. on Humulus lupulus L. (HOPs) and in the Soils in which it is Grown at Pazaryeri/Bilecik Region in Turkey

Investigation of Fusarium spp. on Humulus lupulus L. (HOPs) and in the Soils in which it is Grown at Pazaryeri/Bilecik Region in TurkeySeda ÖZTAŞ TARI1, Rasime DEMİREL2*ORCID: 0009-0009-4879-1546; 0000-0001-6702-489X1 Eskisehir Technical University, Institute of Science and Technology, Department of Biology, Eskisehir, Turkey2 Eskisehir Technical University, Institute of Science and Technology, Department of Biology, Eskisehir, Turkey*Correnponding author: rasimed@eskisehir.edu.trAbstractPurpose: This study aimed to investigate the occurrence, diversity, distribution, and seasonal dynamics of Fusarium species associated with hop (Humulus lupulus L.) plants and hop-cultivated soils in Pazaryeri (Bilecik, Türkiye), the only commercial hop-growing region in the country. Morphological and multilocus molecular identification methods were employed to characterize the isolates and evaluate biodiversity patterns in relation to environmental conditions.Materials and Methods: Soil and hop samples were collected from production fields in Pazaryeri during September 2022 and August 2023. Fusarium isolates were recovered using selective media (SNA and SFA supplemented with Rose Bengal). Species identification was performed based on morphological characteristics and multilocus sequence analyses of the ITS and TEF1 gene regions. Phylogenetic analyses were conducted using MEGA 11.0, while community structure and diversity were assessed using Bray–Curtis similarity, Shannon diversity, and Simpson diversity indices.Results: A total of 98 Fusarium isolates were obtained, including 71 from soil samples and 27 from hop plant tissues. Morphological and molecular analyses identified eight species: Fusarium oxysporum, F. venenatum, F. solani, F. acuminatum, F. equiseti, F. camptoceras, F. coeruleum, and F. redolens. F. oxysporum was the most prevalent species (25.51%), followed by F. venenatum (17.35%) and F. solani (15.31%). Biodiversity analyses revealed high species diversity within the study area and demonstrated that seasonal variation significantly influenced species dominance and distribution patterns. Furthermore, F. venenatum and F. camptoceras were recorded for the first time in Türkiye.Conclusion: This study provides the first comprehensive assessment of Fusarium communities associated with hop cultivation in Türkiye. The findings indicate that hop-cultivated soils serve as important reservoirs for diverse Fusarium species, which can subsequently colonize plant tissues during growth. Environmental factors, particularly seasonal conditions and wind patterns, influence the distribution and dispersal of these fungi. The detection of two previously unreported species highlights the ecological significance of the region and contributes valuable information to the Turkish mycobiota. These results provide a foundation for future disease management and monitoring programs in hop production systems.Keywords: Humulus lupulus, Fusarium sp., Pazaryeri, biodiversity