Fungal material
Saprotrophic fungi were isolated from soil samples derived from a grassland site in northern Germany (“Oderhänge Mallnow” close to the town of Lebus, Germany; 52°13´N, 14°13´E) (Andrade-Linares et al.2016). This fungal collection of overall 31 isolates has been characterized in detail in previous studies (Zheng et al. 2018; Lehmann et al. 2019), and covers Mucoromycota, Basidiomycota and Ascomycota (see Table S1).
Before the experiment, each isolate used here was divided into three repetitions and cultured separately on potato-dextrose agar with antibiotics to eliminate potential contaminants. Subsequently, repetitions were transferred to water agar (1.5 %), in order to reduce nutrient storage in fungal tissues. Hereafter, the three repetitions were analyzed separately for each fungal isolate and treatment.