Division of Environment and Natural Resources

Biotechnological solutions for optimal performance of mycorrhiza inoculants in plant production

Active Last updated: 25.01.2018
End: dec 2019
Start: mar 2017

Arable soil contains microorganisms that are hampering the formation and functioning of arbuscular mycorrhiza. The OPTIMYC project aims at identifying which organisms and microbial metabolites that are involved in suppression of arbuscular mycorrhiza

Start - end date 27.03.2017 - 31.12.2019
Project manager Erik J. Joner
Division Division of Environment and Natural Resources
Department Biogeochemistry and Soil Quality
Partners Institute Plant and Environmental Sciences, University of Copenhagen

World food demand is increasing, and it is a major challenge that food production depends on phosphate (P) rock that is non-renewable on a human time scale. Paradoxically, while P sources for fertilizer production are diminishing, large P pools have accumulated in soil due to inefficient plant uptake of P from fertilizers. Crop plants engage in associations with  microorganisms to access soil P, and environmental biotechnology currently develops microbial inoculant solutions for improved P mobilization. The use of inoculants is considered essential for obtaining sustainable food production in a bio-based society.

Arbuscular mycorrhizal fungi (AMF) are important inoculant organisms to promote plant P nutrition as they expand the soil volume that plants scavenge for P. However, unidentified members of the soil microbiome suppress the growth and P uptake of AMF. This underpins the need to understand the ecology of microbial inoculants to optimize their performance. This project aims to identify the microorganisms and the metabolites causing the suppression of AMF and will develop strategies to counteract the suppression.

Suppressive groups of microorganisms will be identified by gene sequence analysis of the microbiome of contrasting soils, and cultures will be established of members that are unique to suppressive soils. Cultures will be selected for their AMF suppressive potential. Chemical fingerprints of metabolites will be obtained for the selected microorganisms and candidate suppressive metabolites will be identified by comparing with fingerprints for suppressive and conducive soils. The suppressive potential of the identified metabolites will be tested in AMF model systems. The generated information on AMF suppressive metabolites and microorganisms will be used to develop diagnostic tools to determine their presence in soil and to select AMF inoculant strains that are resistant to the suppressor agents and hence of potential use as next generation inoculants.