TY - JOUR

T1 - Long-Term Fertilization Strategy Impacts Rhizoctonia solani–Microbe Interactions in Soil and Rhizosphere and Defense Responses in Lettuce

AU - Sommermann, Loreen

AU - Babin, Doreen

AU - Behr, Jan Helge

AU - Chowdhury, Soumitra Paul

AU - Sandmann, Martin

AU - Windisch, Saskia

AU - Neumann, Günter

AU - Nesme, Joseph

AU - Sørensen, Søren J.

AU - Schellenberg, Ingo

AU - Rothballer, Michael

AU - Geistlinger, Joerg

AU - Smalla, Kornelia

AU - Grosch, Rita

N1 - Publisher Copyright: © 2022 by the authors.

PY - 2022

Y1 - 2022

N2 - The long-term effects of agricultural management such as different fertilization strategies on soil microbiota and soil suppressiveness against plant pathogens are crucial. Therefore, the suppressiveness of soils differing in fertilization history was assessed using two Rhizoctonia solani isolates and their respective host plants (lettuce, sugar beet) in pot experiments. Further, the effects of fertilization history and the pathogen R. solani AG1-IB on the bulk soil, root-associated soil and rhizosphere microbiota of lettuce were analyzed based on amplicon sequencing of the 16S rRNA gene and ITS2 region. Organic fertilization history supported the spread of the soil-borne pathogens compared to long-term mineral fertilization. The fertilization strategy affected bacterial and fungal community composition in the root-associated soil and rhizosphere, respectively, but only the fungal community shifted in response to the inoculated pathogen. The potential plant-beneficial genus Talaromyces was enriched in the rhizosphere by organic fertilization and presence of the pathogen. Moreover, increased expression levels of defense-related genes in shoots of lettuce were observed in the soil with organic fertilization history, both in the absence and presence of the pathogen. This may reflect the enrichment of potential plant-beneficial microorganisms in the rhizosphere, but also pathogen infestation. However, enhanced defense responses resulted in retarded plant growth in the presence of R. solani (plant growth/defense tradeoff).

AB - The long-term effects of agricultural management such as different fertilization strategies on soil microbiota and soil suppressiveness against plant pathogens are crucial. Therefore, the suppressiveness of soils differing in fertilization history was assessed using two Rhizoctonia solani isolates and their respective host plants (lettuce, sugar beet) in pot experiments. Further, the effects of fertilization history and the pathogen R. solani AG1-IB on the bulk soil, root-associated soil and rhizosphere microbiota of lettuce were analyzed based on amplicon sequencing of the 16S rRNA gene and ITS2 region. Organic fertilization history supported the spread of the soil-borne pathogens compared to long-term mineral fertilization. The fertilization strategy affected bacterial and fungal community composition in the root-associated soil and rhizosphere, respectively, but only the fungal community shifted in response to the inoculated pathogen. The potential plant-beneficial genus Talaromyces was enriched in the rhizosphere by organic fertilization and presence of the pathogen. Moreover, increased expression levels of defense-related genes in shoots of lettuce were observed in the soil with organic fertilization history, both in the absence and presence of the pathogen. This may reflect the enrichment of potential plant-beneficial microorganisms in the rhizosphere, but also pathogen infestation. However, enhanced defense responses resulted in retarded plant growth in the presence of R. solani (plant growth/defense tradeoff).

KW - 16S rRNA gene

KW - fungal ITS sequences

KW - high-throughput amplicon sequencing

KW - organic and mineral fertilization

KW - plant gene expression

KW - Rhizoctonia solani

KW - Talaromyces

U2 - 10.3390/microorganisms10091717

DO - 10.3390/microorganisms10091717

M3 - Journal article

C2 - 36144319

AN - SCOPUS:85138715930

VL - 10

JO - Microorganisms

JF - Microorganisms

SN - 2076-2607

IS - 9

M1 - 1717

ER -