A check list of non-lichenised fungi occurring on Fagus crenata, a tree endemic to Japan

Fungi associated with woody tissues of Acer pseudoplatanus in forest stands with different health status concerning sooty bark disease (Cryptostroma corticale)

From 2018 to 2020, Germany experienced periods of exceptional weather conditions. Extremely high summer temperatures and precipitation deficits induced stress and mortality in forest trees. Acer pseudoplatanus (sycamore) was one of the affected tree species. Symptoms of sooty bark disease (SBD) and severe damage of entire stands, both caused by the fungal species Cryptostroma corticale, were reported more frequently. To explore the non-symptomatic distribution of C. corticale, wood cores from visibly healthy sycamore stems were sampled and all outgrowing fungi were identified and recorded. In total, 50 trees, aged 30–65 years, were sampled at five different forest stands, from which 91 endophytic filamentous morphotypes could be isolated. The fungal endophytic community in the woody tissue of the sycamore trees varied greatly at the different sites and between the trees. The number of isolated morphotypes at the different sites ranged from 13 to 44 and no morphotype was found at all sites. At 1.20-m stem height, 3.3 fungi could be isolated from woody tissue per tree on average. The most abundant species isolated from visibly healthy sycamore in regard to both occurrence at the studied sites and continuity was C. corticale. It was recorded at four of the studied forest stands, from 26% of all studied sycamore trees, and had a frequency of 7.85% relative to the 293 isolated filamentous strains that were isolated. The second most abundant species was Xylaria longipes followed by Lopadostoma turgidum. In this study clear evidence for the endophytic lifestyle of C. corticale is presented which thus appears to be spread further than expected based on visible SBD symptoms.

Systematics, ecology, and application of Helotiales: Recent progress and future perspectives for research with special emphasis on activities within Japan

Helotiales is one of the most diverse groups of apothecial ascomycetes, including 3000-4000 taxa. Recent progress in the systematics, ecology, and their applications through research is herein reviewed based on the experiences of the author with a special emphasis on activities in Japan. In the past 30 y, more than 50 helotialean taxa have been added to the mycobiota of Japan, including new taxa. With the advent of molecular phylogeny, some families have been revisited, such as members with stroma (Sclerotiniaceae and Rutstroemiaceae) or hairs (Hyaloscyphaceae and Lachnaceae). Although the monophyly of Helotiales has not yet been demonstrated, our understanding of its phylogeny has greatly advanced. The unexpected ecological nature represented by endophytism has been revealed through barcoding and other molecular techniques. The research history of ash dieback is also reviewed, and the endophytism/saprophytism of the pathogen on its original host is discussed. Drug discoveries within Helotiales are reviewed, and successful examples are presented. As future perspectives, both the cumulation of occurrence and sequence data of Helotiales is greatly encouraged to elucidate this important group of fungi.