Root colonization with arbuscular mycorrhizal fungi and glomalin-related soil protein (GRSP) concentration in hypoxic soils in natural CO2 springs

Authors

• Irena Maček University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, SI-1001 Ljubljana, Slovenia
• Damijana Kastelec University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, SI-1001 Ljubljana, Slovenia
• Dominik Vodnik University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, SI-1001 Ljubljana, Slovenia

DOI: https://doi.org/10.23986/afsci.5006

Keywords:

arbuscular mycorrhizal fungi, Glomeromycota, root colonization, GRSP, glomalin, natural CO2 springs, mofette, hypoxia, abiotic factors, extreme habitat, spatial distribution, soil fungi

Abstract

Changed ratios of soil gases that lead to hypoxia are most often present in waterlogged soils, but can also appear in soils not saturated with water. In natural CO₂ springs (mofettes), gases in soil air differ from those in typical soils. In this study, plant roots from the mofette area Stavešinci (Slovenia) were sampled in a spatial scale and investigated for AM fungal colonization. AM fungi were found in roots from areas with high geological CO₂ concentration, however mycorrhizal intensity was relatively low and no correlation between AM fungal colonization and soil pattern of CO₂/O₂ concentrations (up to 37% CO₂) was found. The relatively high abundance of arbuscules in root cortex indicated existence of functional symbiosis at much higher CO₂ concentrations than normally found in soils. In addition, concentration of two different glomalin-related soil protein fractions – EE-GRSP and TG-GRSP – was measured. No significant correlation between any of the fractions and soil gases was found, however the concentration of both fractions was significantly higher in the upper 0–5 cm, compared to the 5–10 cm layer of the soil.