EFS12- Book of abstracts - Contact

SESSION 1: FUSARIUM – GENETICS, GENOMICS AND SYSTEMS BIOLOGY
P11 - Identifying indicators of soil suppressiveness to
fungal diseases
K. Siegel 1 , S. Aimé 1 , E. Chapelle 2 , V. Edel-Hermann 1 , J. Raaijmaakers 2 , P.
Lemanceau 1* , C. Steinberg 1
1 INRA, UMR1347 Agroécologie, 17 rue Sully, BP 86510, 21065 Dijon, France; 2 Wageningen
University; Bld 107, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands; * Coordinator of
the EU project Ecofinders FP7-ENV-2010-264465
E-mail: christian.steinberg@dijon.inra.fr
Soils suppressive to soil-borne diseases are defined by a low disease incidence in
spite of the presence of a virulent pathogen and a susceptible plant. In many
cases, the inhibition of the disease development relies on the activity of the
resident soil microbiome.
To identify taxonomic microbial indicators linked to the suppressiveness
phenotype of soils, culture independent-based methods have been employed to
analyse and compare microbial dynamics in two different soils suppressive to
either Rhizoctonia solani damping-off disease of sugar beet or Fusarium wilt
disease on flax. Fungal and bacterial taxonomic biodiversity were estimated from
ITS and 16S genes by amplicon pyrosequencing. To that end, metagenomic DNA
was extracted from the rhizosphere of plants grown in soils with different level of
suppressiveness.
We obtained 218650 reads in total (125602 for fungi and 93048 for bacteria). At
this moment, the analyses of fungal communities are in progress. 114641 reads
was kept after filtering by bioinformatic pipeline, distributed into 2303 clusters and
3379 singletons. Although, the bioinformatic and statistical analysis are not
finished yet, we have already noticed a difference in the taxonomic diversity
composition between suppressive and conducive soils which could explain the
suppressive/conducive character of given soil.
The next step is to achieve the bacterial communities in Fusarium wilt
suppressive/conducive soils and to assess the microbial diversity of other soilborne
diseases suppressive soils. Once the analyses of sequencing data are
finished and the taxonomic assignments done, the comparison of microbial
diversity of all studied soils will be performed in order to find out the similarities
or/and differences in these soils which will provide the suppressiveness
indicators.
Keywords: Châteaurenard, Ecofinders, Fusarium oxysporum, Soil-borne disease
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