TY - JOUR

T1 - Legacy effects of pre-crop plant functional group on fungal root symbionts of barley

AU - Roy, Julien

AU - van Duijnen, Richard

AU - Leifheit, Eva F.

AU - Mbedi, Susan

AU - Temperton, Victoria Martine

AU - Rillig, Matthias C.

N1 - Funding Information: This work was supported by the German Federal Ministry of Education and Research (BMBF) initiative ‘BonaRes—Soil as a sustainable resource for the bioeconomy’ through the project INPLAMINT (grant number: 031B0508B). E. F. Leifheit acknowledges funding from the Deutsche Forschungsgemeinschaft (LE 3859/1‐1). We thank Max Fussan and Tobias Wiesner for help with measuring soil and root colonization. We thank Paul Gentil for help with root DNA extraction. We thank the DAAD AIESTE and RISE programmes for funding student helpers and Christoph Schmidt, Arthur César Coares, Douglas Henrique, Farida Samad‐Zada, and Phong Hong in helping to set up, manage, and harvest the mesocosm experiment. Author contributions: R. van Duijnen, J. Roy, V. Temperton, and M. C. Rillig designed the experiment. R. van Duijnen performed the mesocosm experiment. R. van Duijnen and J. Roy performed soil and root sampling. J. Roy performed molecular analyses and analyzed data, M. C. Rillig and S. Mbedi contributed new reagents or analytical tools. J. Roy wrote the manuscript, which was revised by all authors. Publisher Copyright: © 2021 The Authors. Ecological Applications published byWiley Periodicals LLC on behalf of Ecological Society of America.

PY - 2021/9

Y1 - 2021/9

N2 - Arbuscular mycorrhizal (AM) fungi, a group of widespread fungal symbionts of crops, could be important in driving crop yield across crop rotations through plant–soil feedbacks (PSF). However, whether preceding crops have a legacy effect on the AM fungi of the subsequent crop is poorly known. We set up an outdoor mesocosm crop rotation experiment that consisted of a first phase growing either one of four pre-crops establishing AM and/or rhizobial symbiosis or not (spring barley, faba bean, lupine, canola), followed by an AM crop, winter barley. After the pre-crop harvest, carbon-rich organic substrates were applied to test whether it attenuated, accentuated or modified the effect of pre-crops. The pre-crop mycorrhizal status, but not its rhizobial status, affected the richness and composition of AM fungi, and this difference, in particular community composition, persisted and increased in the roots of winter barley. The effect of a pre-crop was driven by its single symbiotic group, not its mixed symbiotic group and/or by a crop-species-specific effect. This demonstrates that the pre-crop symbiotic group has lasting legacy effects on the AM fungal communities and may steer the AM fungal community succession across rotation phases. This effect was accentuated by sawdust amendment, but not wheat straw. Based on the previous observation of decreased crop yield after AM pre-crops, our findings suggest negative PSF at the level of the plant symbiotic group driven by a legacy effect of crop rotation history on AM fungal communities, and that a focus on crop symbiotic group offers additional understanding of PSF.

AB - Arbuscular mycorrhizal (AM) fungi, a group of widespread fungal symbionts of crops, could be important in driving crop yield across crop rotations through plant–soil feedbacks (PSF). However, whether preceding crops have a legacy effect on the AM fungi of the subsequent crop is poorly known. We set up an outdoor mesocosm crop rotation experiment that consisted of a first phase growing either one of four pre-crops establishing AM and/or rhizobial symbiosis or not (spring barley, faba bean, lupine, canola), followed by an AM crop, winter barley. After the pre-crop harvest, carbon-rich organic substrates were applied to test whether it attenuated, accentuated or modified the effect of pre-crops. The pre-crop mycorrhizal status, but not its rhizobial status, affected the richness and composition of AM fungi, and this difference, in particular community composition, persisted and increased in the roots of winter barley. The effect of a pre-crop was driven by its single symbiotic group, not its mixed symbiotic group and/or by a crop-species-specific effect. This demonstrates that the pre-crop symbiotic group has lasting legacy effects on the AM fungal communities and may steer the AM fungal community succession across rotation phases. This effect was accentuated by sawdust amendment, but not wheat straw. Based on the previous observation of decreased crop yield after AM pre-crops, our findings suggest negative PSF at the level of the plant symbiotic group driven by a legacy effect of crop rotation history on AM fungal communities, and that a focus on crop symbiotic group offers additional understanding of PSF.

KW - Ecosystems Research

KW - agro-ecosystems

KW - amplicon sequence variants

KW - arbuscular mycorrhizal fungi

KW - crop rotation

KW - mesocosm experiment

KW - phylogenetic scale

KW - plant-soil feedback

KW - sustainable agriculture

KW - agro-ecosystems

KW - amplicon sequence variants

KW - arbuscular mycorrhizal fungi

KW - crop rotation

KW - mesocosm experiment

KW - phylogenetic scale

KW - plant–soil feedback

KW - sustainable agriculture

UR - http://www.scopus.com/inward/record.url?scp=85109292132&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/e910e884-25d4-3493-9e98-0575f86edb07/

U2 - 10.1002/eap.2378

DO - 10.1002/eap.2378

M3 - Journal articles

C2 - 33988274

VL - 31

JO - Ecological Applications

JF - Ecological Applications

SN - 1051-0761

IS - 6

M1 - e02378

ER -