First record of Erysiphe salmonii causing powdery mildew on Fraxinus ornus in Switzerland

New disease reports

article

L. Beenken¹  T. Brodtbeck² 

[1] Swiss Federal Research Institute WSL;Elsternweg 5

关键词: Erysiphales;    manna ash;    obligate parasite;    Uncinula;   

DOI  :  10.5197/j.2044-0588.2020.042.022

学科分类：生物科学（综合）

来源: British Society for Plant Pathology

【 摘 要 】

In Switzerland, the manna ash (Fraxinus ornus) is native to thecanton Ticino (https://www.infoflora.ch). In September and October 2020,a powdery mildew species of the genus Erysiphe sect. Uncinula wasdiscovered in four native stands of F. ornus in southern Ticino. These wereon the southern slope of Mt. Brè between Lugano and Gandria (ZT Myc64438), at Mt. San Salvatore close to its summit (ZT Myc 64439), at Mt.San Giorgio close to Meride (ZT Myc 64440) and north of MorbioInferiore (ZT Myc 64441) (ZT Myc = vouchers in fungal herbarium ofETH Zurich). In these areas, the species was found on several seedlings andmature trees and therefore the disease is considered widespread where it isfound. The current distribution in Switzerland will be continuously updatedon https://swissfungi.wsl.ch/en/distribution-data/distribution-atlas.html.The morphological characteristics of the chasmothecia found on the leavesbut rarely on the fruits of F. ornus fit Erysiphe salmonii as described andillustrated in Braun & Cook (2012) and Heluta et al. (2017). Mycelium wasamphigenous but mainly epiphyllous. Chasmothecia were scattered andmeasured 80-120 µm in diameter, had 10-20 appendices, 70-130 µm longand 5-7 µm wide (to 9 µm towards the tip), which were pigmented at thebase and with one septum. Apices were spirally curved. Chasmothecia had2-5 ovoid asci measuring 50-60 × 30-50 µm with 6-8 ellipsoid ascosporesper ascus, each measuring 15-20 × 7-10 µm. Conidiophores and conidiawere not observed.

【 授权许可】

CC BY