Abstract: Septorioides strobi Wyka et Broders (Ascomycota, Botryosphaeriales, Septorioideaceae), the causal agent of Septorioides needle blight, was detected for the first time in Bulgaria and Europe in 2023. Over the past three years, the pathogen has caused significant damage of Pinus sylvestris L. within the State Forest Enterprises (SFEs) Ardino, Smilyan, Smolyan, Zlatograd (South-eastern Bulgaria), and of P. nigra Arn. in SFE Karlovo (South-central Bulgaria). In most plantations, S. strobi occurred together with other fungal pathogens, including Lecanosticta acicola (von Thümen) Sydow, Diplodia sapinea (Fries) Fuckel, Cyclaneusma minus (Butin) DiCosmo, Peredo et Minter, Pestalotiopsis funerea (Desmazières) Steyaert, and Lophodermium sp. The spread of the disease in pine plantations was documented from 2023 to 2025.
Keywords: Europe, first record, pine plantations, Septorioides needle blight, Septorioides strobi
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Additional information
Received: 26 May 2026 · Accepted: 2 October 2026
Editor: Stanislav Abadjiev
Conflicts of interest:
No potential conflict of interest has been reported by the authors, reviewers, or subject editor.
Authors’ contributions (using CrediT ↗):
Maria Dobreva: data curation, investigation, resources, visualisation, writing—original draft; Margarita Georgieva: data curation, writing—original draft; Pencho Dermendzhiev: data curation, investigation, resources; Rumen Nachev: investigation, resources; Georgi Georgiev: data curation, writing—original draft.
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Cite as
Dobreva M., Georgieva M., Dermendzhiev P., Nachev R., Georgiev G. 2026 First record of Septorioides strobi Wyka & Broders (Septorioidaceae) in pine plantations in Bulgaria. Historia naturalis bulgarica 48: 419–424.