https://phaidra.vetmeduni.ac.at/o:5457 Arbuscular mycorrhizal fungal families and exploration‐based guilds exhibit distinct responses to long‐term N, P and K deficiencies and imbalances Jenab, Kian Kian Jenab 0000-0003-1323-7827 Alteio, Lauren Lauren Alteio 0000-0002-9108-5083 Guseva, Ksenia Ksenia Guseva 0000-0002-5139-7138 Gorka, Stefan Stefan Gorka 0000-0003-2046-7567 Darcy, Sean Sean Darcy 0000-0001-5967-3742 Fuchslueger, Lucia Lucia Fuchslueger 0000-0002-9615-4439 Canarini, Alberto Alberto Canarini 0000-0003-2516-5955 Martin, Victoria Victoria Martin 0000-0002-7473-1039 Wiesenbauer, Julia Julia Wiesenbauer 0009-0004-9237-6802 Spiegel, Felix Felix Spiegel 0000-0003-0691-7656 University of Veterinary Medicine Vienna. Centre for Food Science Imai, Bruna Bruna Imai Schmidt, Hannes Hannes Schmidt 0000-0003-4288-4257 Hage‐Ahmed, Karin Karin Hage‐Ahmed 0000-0001-7711-8101 Pötsch, Erich M. Erich M. Pötsch 0000-0002-0564-8135 Richter, Andreas Andreas Richter 0000-0003-3282-4808 Jansa, Jan Jan Jansa 0000-0002-0331-1774 Kaiser, Christina Christina Kaiser 0000-0002-2005-1820 Wiley journal article open access eng Many agroecosystems face nitrogen (N), phosphorus (P) or potassium (K) deficiencies due to imbalanced or insufficient nutrient replenishment after biomass harvest. How this affects the symbiosis between plants and arbuscular mycorrhizal fungi (AMF) and the abundance of exploration-based AMF guilds (rhizophilic, edaphophilic and ancestral) remains largely unknown. We studied a 70-yr nutrient deficiency experiment in a managed grassland in central Austria, where aboveground biomass was harvested three times annually. N, P and K were fully, partially or not replenished, causing long-term nutrient deficiencies and imbalances. We analysed AMF communities in soil and roots by DNA/RNA amplicon sequencing and fatty acid biomarkers, alongside soil and plant community properties. Soil AMF communities were affected by N and P deficiencies, while root AMF communities were most susceptible to K deficiency, showing up to 50% biomass reduction, particularly when N was abundant. We observed a shift from rhizophilic to ancestral guilds under P deficiency in soil, and under K deficiency in roots. Families within each guild, particularly ancestral, showed differential responses, indicating complementary nutrient specializations at the family level. Our findings underscore the previously unrecognized role of K deficiency in AMF symbiosis and suggest the existence of nutrient-related functional subgroups within exploration-based AMF guilds. Keywords AMF abundance and community composition ancestral arbuscular mycorrhizal fungi edaphophilic exploration-based functional guild long-term nutrient deficiencies and imbalances managed grassland rhizophilic http://creativecommons.org/licenses/by/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:5457/download 10.1111/nph.70969 https://phaidra.vetmeduni.ac.at/o:605 application/pdf New Phytologist issn:0028-646X VoR New Phytologist 250 3 2.81 MB 2026