Activity profiling of ectomycorrhiza communities in two forest soils using multiple enzymatic tests

Area of Science:

• Mycology
• Soil Science
• Ecology

Background:

• Ectomycorrhizal (ECM) fungi play vital roles in forest ecosystems, influencing nutrient cycling and plant health.
• Current understanding of the diversity and distribution of enzyme activities within native ECM communities is limited.
• Enzymes produced by ECM fungi are essential for decomposing complex organic compounds like lignocellulose and chitin.

Purpose of the Study:

• To develop and validate a novel microplate-based assay for measuring multiple enzyme activities in individual ECM root tips.
• To characterize the functional diversity and activity profiles of ECM communities in different forest soil horizons.
• To investigate the distribution of enzymatic capabilities among different ECM fungal symbionts.

Main Methods:

• Development of a microplate multiple enzymatic test capable of assaying eight distinct enzyme activities.
• Application of the test to 14 individual, excised ECM root tips from two distinct forest sites.
• Analysis of hydrolytic and oxidative enzyme activities related to the decomposition of lignocellulose, chitin, and organic phosphorus compounds.

Main Results:

• The developed test system demonstrated high accuracy and sensitivity in profiling ECM enzyme activities.
• Significant diversity in activity profiles was observed, varying with fungal symbiont identity and soil horizon.
• ECM fungi were categorized as specialists or generalists, with complementary roles within the same soil horizon.

Conclusions:

• ECM activity profiling using the microplate assay is a valuable tool for assessing functional diversity in ECM communities.
• The findings highlight the specialized and complementary roles of ECM fungi in soil organic matter decomposition.
• Further research with expanded assays can provide deeper insights into ECM functional ecology and ecosystem processes.