Biomass of external mycelium of ectomycorrhizal fungi associated with poplars – The impact of tree genotype, tree age and soil environment

Abstract

The external mycelium (EM) is an important structural element of the symbiosis between mycorrhizal fungi and trees, fulfilling several important functions in their development and playing a significant role in carbon and nitrogen cycling in soil. This study aimed to estimate and compare the EM biomass of ectomycorrhizal fungi associated with mature trees and 6-month-old seedlings representing four different poplar genotypes planted in different soil conditions. The fungal-specific ergosterol biomarker was used to estimate the EM biomass. The results showed similar values of EM biomass for mature trees and seedlings. EM biomass was affected by tree genotype. Soil conditions had a greater effect on the EM biomass of seedlings than mature poplars. Seedling results also demonstrated the importance of soil moisture and carbon and nitrogen content on EM biomass. The soil moisture more than heavy metal pollution influenced the EM biomass of seedlings.