Fungal biomass production in response to elevated atmospheric CO2 in a Glomus mosseae Prunus cerasifera model system.

Biomass and length of intraradical and extraradical mycorrhizal mycelium under ambient (aCO2) and elevated (eCO2 ) atmospheric CO2 was investigated using a nondestructive in vivo experimental model system. Time-course experiments allowed measurements of intact extraradical mycelium spreading from mycorrhizal roots of Prunus cerasifera micropropagated plants inoculated with the arbuscular mycorrhizal fungus Glomus mosseae, in controlled environmental chambers. The length of extraradical mycelium was significantly increased at the highest CO2 concentration, ranging from 10.7 to 20.3 m at aCO2 and eCO2, respectively. The biochemical determination of mycelial glucosamine content allowed the evaluation of intraradical and extraradical fungal biomass, which were 2 and 3 times larger at eCO2 than at aCO2. Present data show that Glomus mosseae responds to increases of CO2 concentrations producing larger mycorrhizal networks which may potentially represent carbon sink agents in soil ecosystems.