Quantifying species differences in hyphal persistence between wood decomposing fungi at the microscale

The vegetative mycelium of wood decomposing fungi is indeterminate and ever changing over the course of their lifetime. When it comes to fruiting bodies, we know that there are stark differences between species in terms of how long lasting their fruiting bodies are, with some appearing, ephemerally, for a short moment in the season and others lasting for multiple years. However, for the vegetative mycelium, it is not well known and documented how ephemeral the body of the mycelial network is for the same species.

In this study, we utilized microfluidic chip systems to document, classify and quantify turnover of fungal hyphae in eight different species of basidiomycetes grown with two different carbon sources (glucose or carboxymethylcellulose) to gain a better understanding of how mycelial turnover and potential recycling differs across wood decomposing species.

Our results show that there was a difference between species but not between carbon sources in terms of how quickly and to what degree the mycelium was degenerated. The turnover rate and hyphal persistence of the different species grouped into two distinct clusters. One with low turnover rate and species leaving “skeletonized hyphae” behind and one group that showed a quick and almost full turnover of hyphae (likely through autolysis). These results open up for new questions around species differences in hyphal re-cycling abilities, whether some wood decomposing species could contribute more to carbon sequestration in soils than others and if they have different effects on subsequent succession scenarios due to the different levels of nutrients left behind.