Fungal Growth Rates and Production
Biological, Environmental, and Earth Sciences
Fungi are key components in the decomposition of plant litter in aquatic environments. Therefore, estimates of rates of fungal growth and biomass production associated with decaying litter are important in assessing the importance of fungi in ecosystems. This chapter describes a method for estimating rates of fungal growth and production. Pieces of plant litter undergoing decomposition are incubated with radiolabelled (14C) acetate for a given time, typically 4 h. Ergosterol, a biomarker largely specific to fungi, is extracted from the litter samples and its concentration determined with HPLC to estimate fungal biomass. The ergosterol fraction eluting from the HPLC column is collected and its radioactivity determined in a scintillation counter to estimate rates of acetate incorporation into ergosterol. Fungal growth rates are directly proportional to acetate incorporation rates, and fungal production is calculated as the product of fungal growth rate and biomass. Production can be expressed per gram of litter or, if the amount of litter is known, per square metre of the environment such as a stream. Application of the method has shown that fungal growth and production can be substantial in streams and other environments, depending on factors such as litter type, nutrient concentrations and temperature.
Methods to Study Litter Decomposition
(2020). Fungal Growth Rates and Production. Methods to Study Litter Decomposition, 254-264.
Available at: https://aquila.usm.edu/fac_pubs/20791