TY - JOUR

T1 - Exploring microbial determinants of apple replant disease (ARD)

T2 - a microhabitat approach under split-root design

AU - Balbín-Suárez, Alicia

AU - Lucas, Maik

AU - Vetterlein, Doris

AU - Sørensen, Søren J.

AU - Winkelmann, Traud

AU - Smalla, Kornelia

AU - Jacquiod, Samuel

PY - 2020

Y1 - 2020

N2 - Apple replant disease (ARD) occurs worldwide in apple orchards and nurseries and leads to a severe growth and productivity decline. Despite research on the topic, its causality remains unclear. In a split-root experiment, we grew ARD-susceptible 'M26' apple rootstocks in different substrate combinations (+ARD: ARD soil; -ARD: gamma-irradiated ARD soil; and Control: soil with no apple history). We investigated the microbial community composition by 16S rRNA gene amplicon sequencing (bacteria and archaea) along the soil-root continuum (bulk soil, rhizosphere and rhizoplane). Significant differences in microbial community composition and structure were found between +ARD and -ARD or +ARD and Control along the soil-root continuum, even for plants exposed simultaneously to two different substrates (-ARD/+ARD and Control/+ARD). The substrates in the respective split-root compartment defined the assembly of root-associated microbial communities, being hardly influenced by the type of substrate in the respective neighbor compartment. Root-associated representatives from Actinobacteria were the most dynamic taxa in response to the treatments, suggesting a pivotal role in ARD. Altogether, we evidenced an altered state of the microbial community in the +ARD soil, displaying altered alpha- and beta-diversity, which in turn will also impact the normal development of apple rhizosphere and rhizoplane microbiota (dysbiosis), concurring with symptom appearance.

AB - Apple replant disease (ARD) occurs worldwide in apple orchards and nurseries and leads to a severe growth and productivity decline. Despite research on the topic, its causality remains unclear. In a split-root experiment, we grew ARD-susceptible 'M26' apple rootstocks in different substrate combinations (+ARD: ARD soil; -ARD: gamma-irradiated ARD soil; and Control: soil with no apple history). We investigated the microbial community composition by 16S rRNA gene amplicon sequencing (bacteria and archaea) along the soil-root continuum (bulk soil, rhizosphere and rhizoplane). Significant differences in microbial community composition and structure were found between +ARD and -ARD or +ARD and Control along the soil-root continuum, even for plants exposed simultaneously to two different substrates (-ARD/+ARD and Control/+ARD). The substrates in the respective split-root compartment defined the assembly of root-associated microbial communities, being hardly influenced by the type of substrate in the respective neighbor compartment. Root-associated representatives from Actinobacteria were the most dynamic taxa in response to the treatments, suggesting a pivotal role in ARD. Altogether, we evidenced an altered state of the microbial community in the +ARD soil, displaying altered alpha- and beta-diversity, which in turn will also impact the normal development of apple rhizosphere and rhizoplane microbiota (dysbiosis), concurring with symptom appearance.

KW - Malus domestica

KW - apple replant disease

KW - microbiome

KW - rhizoplane

KW - rhizosphere

U2 - 10.1093/femsec/fiaa211

DO - 10.1093/femsec/fiaa211

M3 - Journal article

C2 - 33045057

AN - SCOPUS:85097968033

VL - 96

JO - F E M S Microbiology Ecology

JF - F E M S Microbiology Ecology

SN - 0168-6496

IS - 12

M1 - fiaa211

ER -