Additional experiments evaluating N and P allocation in mycelia
Stoichiometric data derived from nutrient gradient tests suggested a differential allocation of N and P in fungal mycelia during growth. To test such patterns of element allocation, data of fungal strains growing on SEA and glucose media were analyzed in this context.
12 fungal strains (RLCS01, RLCS16, RLCS27, RLCS15, RLCS13, RLCS28, RLCS22, RLCS17, RLCS09, RLCS18, RLCS12, RLCS11; n=3) were grown on SEA, analyzing N contents after 12 and 26 days. Additionally, the N content of inner and outer mycelium of four strains (RLCS12, RLCS16, RLCS22, RLCS28; n=3) was analyzed after 26 days of growth. Therefore, the radius of fungal mycelia at four positions was determined, and partitioned by 2/3 (inner) and 1/3 (outer). Mycelia were cut and divided into inner and outer parts according to this separation, and element contents analyzed separately.
Similarly, in an additional nutrient manipulation experiment the inner and outer mycelium of fungi grown in glucose media with high N (C:N 20) and low N content (C:N 200) were harvested separately using the same mycelial partitioning. Four fungal strains were selected based on large variation of 1/HCN values see below), also using fungal strains previously characterized in another study (RLCS06, RLCS18, RLCS09, RLCS13; unpublished data).