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Managing the soil microbiome –key for plant health and growth
Kornelia Smalla
Julius Kühn-Institute, [email protected]
The rhizosphere is the zone of soil influenced/altered by roots.
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How agricultural management influences the soilmicrobiome?
How to manage the soil microbiome throughOrganic amendmentsCover cropsTillageCrop rotationInoculants
Exploration of plant-microbe-interactions forimproving agricultural productivity andsustainability
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INIA-JKI workshop 14-16 November 2019, Montevideo-Las Brujas, Uruguay„Towards a more sustainable agriculture through managing the soil microbiome“
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Impact of long-term agricultural management practices on the soil and rhizosphere
microbiome and on plant health
Doreen Babin, Soumitra Paul Chowdhury, Michael Rothballer, Loreen Sommermann, Jörg Geistlinger, Saskia Windisch, Narges Moradtalab, Günther Neumann, Martin Sandmann, Rita Grosch and Kornelia Smalla
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Objective
… soil suppressivenessagainst plant pathogens?
How do long-term farming practicesaffect…
How can socio-economic constellation and understanding be improved?
… establishment andcomposition of the bulk soiland rhizosphere microbiota?
… root exudationpatterns?
… plant performanceand health?
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Do long-term farming strategies shapethe soil microbiota?
6
WW1 Winter wheat after maize
WW2 Winter wheat after rapeseed
P Plough
CT Cultivator
Int Standard N-fertilization + fungicide use
Ext 50% N-fertilization
Long-term field trial in Bernburg(est. 1992, AUAS)
Field soil samples of WW1 & WW2 (0-20 cm)
Total communityDNA extraction
ITS1 and ITS2 fragments
used as fungal marker
16S rRNAgenes used as
bacterial marker
Illumina Amplicon Sequencing
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7
Bacteria Fungi
.
Babin et al. 2019, SBB Sommermann et al. 2018, PlosOne
Plough
Cultivator
WW2
WW1
WW2
WW1
Pre-crop and tillage practices influencedsignificantly bacterial and fungal
communities in field soils
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Soil microbial communities are shaped bylong-term agricultural management practices
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Babin et al. 2019, SBB
Is the effect transmitted to rhizospheremicrobiome of the preceeding crop?Does the effect influence plant performanceand health?
8
Sommermann et al. 2018, PlosOne
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9
Mendes et al.2013, FEMS MR
Hypothesis: soil memory effectThe effect of long-term agricultural management on the soil microbiome is conveyed via rhizosphere microorganisms to the next plant generation affecting plant performance and health
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Growth conditions
10 weeks growth period
20/15 °C day-/night-temperature
60/80 % relative humidity
420 µmol m-2 s-1 PAR
100 hPa water potential
0.32 g available N per pot
Material Soil from LTE-1 Bernburg (AUAS, 1992):
• Soil management:
Plough [P] vs. Cultivator Tillage [CT]
• N-Fertilization intensity:
Intensive [Int] vs. Extensive [Ext]
• Last standing field crop:
Wheat [W] vs. Rapeseed [R]
Lettuce Lactuca sativa L. cv. ‘Tizian’
Growth chamber experiment: Effect of soil management, fertilization intensity and last standing crop
10
Sampling
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Explained Variance Bacteria (Rh) Fungi (RS)
Soil management 13% * 10% *
Fertilization intensity 9%* 16% *
Field crop 15%* 37% *
11
PERMANOVA analysis based on Bray-Curtis dissimilarities, 10,000 permutations (p<0.05)Rh = RhizosphereRS = Root-associated Soil
Soil management, fertilization intensity and field cropaffected the lettuce rhizosphere microbiota
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Management-dependent prokaryoticcommunity composition and enrichment of
genera in the lettuce rhizosphere
CT (except Ext-W):PseudomonasMethylophilus
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Tillage practice and N-fertilization intensity affected significantly lettuce growth
13
• Effect independent of the last standing field crop (wheat [W] and rapeseed [R]) and vegetation period (2015, 2016, 2017)
Shoot fresh mass [g/plant]
Different letters indicate significant difference (Tukey-Test, p<0.05)
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Expression of plant defense-associated genes was by N-fertilization intensity and soil management
Significantly higher expression of plant defense-associated genes in CT-Ext compared to P-Ext suggests an induced physiological status
Reproducible effects in two independent experiments (2015, 2016)
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Fold Change CT-Ext vs. P-Ext (Wheat)
Expression analysis of selected plant genes clustered depending on fertilization intensity
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Summary & Outlook
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Soil/rhizomicrobiota
Root exudation
Lettuce growth Lettuce health
Soil suppressiveness
Long-term field experiment Growth chamber experiment
Better understanding of belowgroundplant-microbe-soil interactions needed
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Use of bacterial endophytes with in vitro antagonistic activity towards Ralstonia solanacearum for biocontrolof bacterial wilt
Tarek Elsayed1, Samuel Jacquiod2, Søren J. Sørensen2, and Kornelia Smalla1
1 Institute for Epidemiology and Pathogen Diagnostics, Julius Kühn-Institut - Federal ResearchCentre for Cultivated Plants (JKI), Braunschweig, Germany2Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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Ralstonia solanacearum is a soil-borne pathogen that naturally infectsroots and invades and multiplies in the xylem vessels and has a verywide host range (more than 200 different plants)
Cell density-dependent expression of virulence genes
The pathogen: Ralstonia solanacearum
Pathogenicity mechanisms: secretion of virulence factors (Type III effectors), enzymatic degradation of host-produced substrates, EPS production
Host colonization and disease requires motility, chemotaxis and aerotaxis
Salicylic acid (SA) inhibits growth of R. solanacearum and induces generalstress response that includes repression of multiple bacterial wilt virulencefactors. The ability to degrade SA reduces the pathogen’s sensitivity toSA toxicity and increases its virulence on tobacco.
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Bacillus velezensis B63Genome size = 4,001,023 bp
Proteins with functional assignments (3,333) Hypothetical proteins (789)
Biological control related secondary metabolites Bacilysin_biosynthetic_gene_cluster Macrolactin_biosynthetic_gene_cluster Bacillaene_biosynthetic_gene_cluster Bacillibactin_biosynthetic_gene_cluster Surfactin_biosynthetic_gene_cluster Fengycin_biosynthetic_gene_cluster
Genome size = 6,538,533 bpProteins with functional assignments (4,630)Hypothetical proteins (1,729)
Biological control related secondary metabolites 2,4-Diacetylphloroglucinol_biosynthetic_gene_clusterSiderophore biosynthesis genePhenazine biosynthesis genePhloroglucinol biosynthesis geneHydrogen cyanide synthase gene
Pseudomonas fluorescens P142
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Transfer to soil infested with 106 B3B CFUs/g
Drenching with antagonists
Seed treatment
Tomato roots
Greenhouse testing of in vitro antagonists towards R. solanacearum in tomato rhizosphere
Greenhouse testing of in vitro antagonists towards R. solanacearum in tomato rhizosphere
Two antagonists were selected
30 dps 14 days after infection
DNA extraction
qPCR targetingRs and gfp‐tagged
antagonists
CFU counts KB, PCA, SMSA
Transfer to non-infested soil
Illumina amplicon sequencing
fliC gene: PCR‐Southern blot hybridization
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Wilting symptoms on tomato plants 14 dpi compared to the control
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CFU counts Real-time PCR
PCR-Southern blot hybridization of fliC gene specific for R. solanacearum in tomato rhizosphere total community DNA samples, two week after transplanting into B3B infested soil
Monitoring inoculant strain and R. solanacearum
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Proteobacteria was the most dominant phylum in control samples (TC) followed by Actinobacteria, Bacteroidetes and Firmicutes.
Relative abundance of Actinobacteria increased in response to antagonist inoculation
Amplicon sequencing of 16S rRNA gene amplified fromTC‐DNA of tomato rhizosphere
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Samples Ralstonia solanacearum OTU_1 Total number of seq. Rs relative % Rs qPCR/g
TC1 ‐ 24395 ‐ ‐TC2 ‐ 19236 ‐ ‐TC3 ‐ 15303 ‐ ‐TC4 ‐ 37015 ‐ ‐TCR1 7386 37458 19.72 8.52TCR2 7547 30359 24.86 8.210TCR3 11258 23683 47.54 8.61TCR4 16426 32675 50.27 8.43
TC‐B63/1 ‐ 29036 ‐ ‐TC‐B63/2 ‐ 38854 ‐ ‐TC‐B63/3 ‐ 35139 ‐ ‐TC‐B63/4 ‐ 25421 ‐ ‐TCR‐B63/1 8 36714 0.02 5.04TCR‐B63/2 57 26975 0.21 5.01TCR‐B63/3 11 23238 0.05 5.16TCR‐B63/4 5 24536 0.02 5.16TC‐142 /1 ‐ 30737 ‐ ‐TC‐142 /2 ‐ 29462 ‐ ‐TC‐142 /3 ‐ 4461 ‐ ‐TC‐142 /4 ‐ 20023 ‐ ‐TCR‐142/1 79 22953 0.34 6.69TCR‐142/2 20 27600 0.07 6.05TCR‐142/3 1 12465 0.01 5.19TCR‐142/4 16 22281 0.07 5.99
Detection of OTU affiliated to R. solanacearum
Lower Rs OTUs in the rhizosphere of tomato plants treated with antagonists
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Shifts of the prokaryotic community compositions inthe tomato rhizosphere in response to the treatments
Dynamic taxaTC-B63: 85 OTUs increased while 31 OTUs decreasedTC-AL2YTEN-142:52 OTUs were increased while 16 OTUs decreased
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Relative abundance of dominant responding genera (Relative abundance ≥ 0.5%)Class Genus OTUs TC TCR TC-B63 TCR-B63 TC-142 TCR-142Actinobacteria Aciditerrimonas OTU_574 0.1 + 0b 0.1 + 0a 0.6 + 0.1d 0.3 + 0c 0.3 + 0.1c 0.2 + 0bc
Curtobacterium OTU_45 0.7 + 0.2b 0.2 + 0.1a 0.5 + 0.2b 0.6 + 0.2b 0.6 + 0.2b 0.7 + 0.1b
Salinibacterium OTU_1281 0.7 + 0.3b 0.2 + 0.1a 0.6 + 0.2b 0.8 + 0.1b 0.7 + 0.2b 0.8 + 0.2b
Arthrobacter OTU_37 4.2 + 1.3b 1 + 0.7a 6.5 + 1.3bc 9 + 1.1c 6.2 + 2.9bc 11 + 1.3c
Nocardioides OTU_371 0 + 0a 0 + 0a 0.6 + 0.2b 0.7 + 0.1b 0.1 + 0a 0.1 + 0a
Gaiella OTU_466 1.1 + 0.2b 0.8 + 0.2a 2.9 + 0.3d 2.2 + 0.3cd 1.8 + 0.4c 1.6 + 0.2c
Rubrobacter OTU_0 3.1 + 1.8bc 0.5 + 0.6a 5.2 + 1.5c 1.3 + 0.8ab 7.7 + 3.3c 2.8 + 0.7bc
Sphingobacteriia Chitinophaga OTU_201 1.4 + 0.8c 0.4 + 0.2ac 0.4 + 0.3ab 1 + 0.5bc 0.5 + 0.5ac 0.2 + 0.2a
Ferruginibacter OTU_827 2.9 + 1.2c 1.8 + 0.7c 0.9 + 0.3ab 0.7 + 0a 1.9 + 0.5c 1.6 + 0.3bc
Niastella OTU_624 0.2 + 0a 0.5 + 0.3b 1.1 + 0.3d 0.9 + 0.3cd 0.5 + 0.1bc 0.6 + 0.2bd
Terrimonas OTU_444 0 + 0a 0 + 0a 0.6 + 0.3c 0.1 + 0ab 0.4 + 0.1c 0.2 + 0.1b
Haliscomenobacter OTU_1954 1.8 + 0.8c 2.2 + 1.7c 0.3 + 0.1a 0.2 + 0a 1.3 + 0.6bc 0.6 + 0.1ab
Pedobacter OTU_183 1.1 + 0.6c 1.1 + 1.2bc 0.1 + 0.1a 0.2 + 0.1ab 0.3 + 0.2ab 0.3 + 0.1ac
Bacilli Bacillus OTU_32 0.9 + 0.5c 0 + 0a 0.2 + 0.1b 0.2 + 0b 0.3 + 0.1b 0.2 + 0.1b
Clostridia Unclass_Lachnospiraceae OTU_199 2.9 + 0.7c 1.3 + 0.4a 3.1 + 0.6c 1.6 + 0.3ab 3.5 + 0.8c 2.4 + 0.4bc
Unclass_Ruminococcaceae OTU_364 1.2 + 0.1b 0.6 + 0.2a 1.3 + 0.1b 1.5 + 0.3b 1.9 + 0.6b 1.3 + 0.4b
Gemmatimonadetes Gemmatimonas OTU_265 0.5 + 0.2ab 0.4 + 0.1a 1.3 + 0.2d 0.7 + 0.1bc 1 + 0.3cd 0.7 + 0.1bc
Alphaproteobacteria Asticcacaulis OTU_12 3.1 + 0.5b 5.5 + 5.2b 0.7 + 0.5a 0.8 + 0.2a 2 + 1.4ab 1.7 + 0.6ab
Brevundimonas OTU_590 0.2 + 0.1ab 0.2 + 0.1a 0.4 + 0.1bc 0.5 + 0.1c 0.8 + 0.4c 0.6 + 0.1c
Bradyrhizobium OTU_10 2.1 + 0.6bc 1 + 0.3a 2.3 + 0.4c 2.4 + 0.2c 1.7 + 0.6bc 1.4 + 0.2ab
Ochrobactrum OTU_669 0.3 + 0.1a 0.3 + 0.1a 0.7 + 0.1b 0.8 + 0bc 0.9 + 0.2bc 1 + 0.2c
Devosia OTU_93 1.5 + 0.2ab 1.2 + 0.4a 2.6 + 0.5c 2.4 + 0.3c 2.3 + 0.3bc 2.3 + 0.5bc
OTU_255 1.5 + 0.2c 0.9 + 0.1b 0.7 + 0.1b 0.4 + 0a 1.5 + 0.2c 1.2 + 0.3c
OTU_244 0.3 + 0.1a 0.4 + 0.2a 0.7 + 0.3bc 0.4 + 0.1a 1.1 + 0.1c 0.5 + 0ab
Rhizobium OTU_173 2 + 0.7c 1.1 + 0.5bc 0.3 + 0.1a 1.1 + 0.4bc 0.6 + 0.2ab 0.8 + 0.2b
Pseudolabrys OTU_118 0.3 + 0ab 0.2 + 0.1a 0.8 + 0.1c 0.8 + 0.1c 0.4 + 0.2b 0.4 + 0.1b
OTU_1424 0.3 + 0.2b 0.2 + 0a 0.9 + 0.1d 0.6 + 0.1cd 0.4 + 0.1bc 0.4 + 0.1b
Unclass_Rhodospirillaceae OTU_108 0.4 + 0.1b 0.1 + 0.1a 1.6 + 0.3c 2.1 + 0.2c 0.3 + 0.1b 0.3 + 0b
Sphingobium OTU_1976 0.2 + 0.2a 0.9 + 0.9b 0.2 + 0ab 0.3 + 0.1ab 0.2 + 0.1a 0.4 + 0.1ab
Sphingomonas OTU_107 1.2 + 0.2b 0.5 + 0.1a 2.5 + 0.6c 2.4 + 0.2c 1.6 + 0.5b 1.5 + 0.3b
OTU_33 1 + 0.1b 0.4 + 0.2a 2.3 + 0.2d 1.3 + 0.2bc 2.2 + 0.4cd 1.4 + 0.2bc
OTU_2099 1.1 + 0.3b 0.4 + 0.1a 1.4 + 0.3bc 2 + 0.2c 0.9 + 0.1b 1.3 + 0bc
Betaproteobacteria Ralstonia OTU_1 0 + 0a 35.8 + 15.7b 0 + 0a 0.1 + 0.1a 0 + 0a 0.1 + 0.2a
Acidovorax OTU_296 0.2 + 0.1a 0.2 + 0.2a 0.8 + 0.1b 0.8 + 0.1b 1 + 1b 0.5 + 0.2ab
Massilia OTU_100 4 + 2.1b 3.5 + 4.3ab 1 + 0.1a 2.4 + 1ab 1.2 + 0.5ab 2.9 + 1.6ab
Shinella OTU_16 5.1 + 1.7b 4.1 + 0.5b 2.5 + 0.5a 8.6 + 1.6c 2.4 + 0.4a 4.7 + 0.9b
GammaproteobacteriaUnclass_Enterobacteriaceae OTU_2015 3.2 + 1.2c 0.5 + 0.4a 3.2 + 0.6c 1.2 + 0.5b 4.1 + 1.2c 1.7 + 0.2bc
Dyella OTU_968 1.1 + 0.7b 0.2 + 0.1a 0.3 + 0.1a 0.2 + 0.1a 0.1 + 0a 0.1 + 0.1a
OTU_1223 0.5 + 0.1b 0.1 + 0a 0 + 0a 0.1 + 0a 0.1 + 0.1a 0.1 + 0.1a
Rhodanobacter OTU_282 9 + 2.7c 2.2 + 0.6b 0.7 + 0a 1.2 + 0.2ab 1.3 + 0.6ab 1.6 + 0.5b
Rudaea OTU_278 0.7 + 0.2bc 0.5 + 0.2b 0 + 0a 0 + 0a 1 + 0.5c 0.7 + 0.2bc
Verrucomicrobiae Luteolibacter OTU_168 0.1 + 0a 0 + 0a 0.5 + 0.2bc 0.3 + 0.1b 0.6 + 0.3c 0.3 + 0.1bc
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R. solanacearum and antagonists CFU counts 14 days post infection. Samples sharing the same letter had no significant differences in the B3B counts.
Monitoring B3B and antagonist´s CFU countsin the rhizosphere
The development of wilting symptoms recorded 14 dpi showed that 19 out of 32
TCR plants (59%) were collapsed
Only 6 out of 32 plants (18.8%) were collapsed in treated plants
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R. solanacearum gene copy numbers determined in total community DNA from tomato rhizosphere and shoot samples by qPCR
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Colonization patterns of P. fluorescens P142Micro-colonies could be observed along the root surface while the endophytic life style of P-142 isolate was observed as the ability to colonize and invade the epiphytic root cells as well as xylem vessels
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Summary
Different soil types and plant spheres harbor different proportions and diversity of antagonists
Plants select bacteria with potential biocontrol activity and the highest proportionof antagonists was observed in the endophytic compartments
Strong reduction of wilting symptoms and B3B abundance in the rhizosphere of tomato plants inoculated with the antagonists revealed byplating, qPCR, Southern blot hybridization and amplicon sequencing
Gfp-positive P-142 were detected in lateral roots, root hairs and epidermal cells and within xylem vessels
Amplicon sequencing of 16S rRNA gene fragments amplified from total community DNA revealed pronounced treatment dependent shifts in bacterial communities in the tomato rhizosphere and numerous dynamictaxa in response to B3B or the inoculants were identified
However, B3B was detected in low numbers in the stem of healthy lookingtomato plants inoculated with P142 indicating latent infections
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Enhanced plant growth in soil under reduced P supply through microbial inoculants and microbiome shifts
Namis Eltlbany1,2,3, Mohamed Baklawa2,3, Ding Guochun4, Nino Weber5, Günter Neumann5, Samuel Jacquiod6 and Kornelia Smalla2
1Abitep GmbH, Glienicker Weg 185, 12489 Berlin, Germany.2Julius Kühn-Institut, Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany3Suez Canal University, Faculty of Agriculture, Ismailia, Egypt.4College of Resources and Environmental Science, China Agricultural University, Beijing 100193, People's Republic of China.5Agroécologie, UMR1347, INRA Centre Dijon, Dijon, France
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Aims of the experiments
Monitoring biostimulants in rhizosphere and bulk soil
• Development and establishment of methods to detect BEs(qPCR, CLSM, selective plating)
• Determination of the ability to colonize the rhizosphere ofinoculated tomato and maize plants (rhizocompetence)
Effect of different biostimulants applications on:
• Plant performance• The accumulation of the nutrients in maize and tomato plants.• Plant-associated microbial communities in rhizosphere and
bulk soil.
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B1: Trianum PB2: ProradixB3: Bacillus amyloliquefaciens FZB42 (FB01 mut1)B4: Pseudomonas sp. RU47
1
2
3
4
5
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7
8
2 Weeks 3 Weeks 4 Weeks 6 Weeks
Log
CFU
/ g fr
esh
root
s
Sampling time
Best rhizosphere competence observed for BE3 (FZB42) and BE4 (RU47) was observed in the rhizosphere of tomato and maize plants
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2 weeks 3 weeks 4 weeks 6 weeks
Log
CFU
/g fr
esh
root
s
Sampling time
Tomato Maize
Rhizocompetence of inoculants followed by selective plating
Effect of microbial biostimulants on the plant growth andindigenous rhizosphere communities of maize andtomato plants grown in soil with reduced P-fertilization
www.julius-kuehn.deBacillus amyloliquefaciens FZB42 (FB01 mut1)
Confocal laser scanning microscopy
Pseudomonas sp. RU47
Root colonization patterns of inoculants followed by
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B0: controlB1: Trianum PB2: ProradixB3: B. amyloliquefaciens FZB42(FB01)B4: Pseudomonas sp. RU47
B0
B1
B2
B3
B4
B0
0
1
2
3
4
B0 B1 B2 B3 B4
Plan
t dry
wei
ght (
g)
BEs application
Tomato
0
2
4
6
8
10
12
B0 B1 B2 B3 B4Pl
ant d
ry w
eigh
t (g)
BEs application
Maize
a aa
b bcc
c cd
B4 (RU47) and B3 (FZB42) increased significantly the growth oftomato and maize.
B1
B2
B3
B4
All bacterial inoculants promoted the growth of tomato and maize.
What is the effect of different inoculants onplant growth six weeks after sowing?
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Analysis of macro-nutrients (P, Mg, Ca and K)in maize plant shoots
0
5
10
15
20
25
30
35
40
45
50
B0 B1 B2 B3 B4
Mac
ro-n
utrie
nts
conc
entr
atio
ns in
mg
/ pla
nt
shoo
t dry
mat
ter
Treatments
PMgCa
0
50
100
150
200
250
300
350
400
450
B0 B1 B2 B3 B4
Mac
ro-n
utrie
nts
conc
entr
atio
ns in
mg
/ pla
nt
shoo
t dry
mat
ter
Treatments
K
B0: controlB1: Trianum PB2: ProradixB3: Bacillus amyloliquefaciensB4: Pseudomonas sp. RU47
aabbc
c
ab
cd
e
a
bbc
cd
a
abbcc
d
The accumulation of the macro-nutrients in the shoot dry matterincreased significantly in all biostimulants applicationP increased significantly only in the treatments with bacterialbiostimulant application.
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B0: controlB1: Trianum PB2: ProradixB3: Bacillus amyloliquefaciensB4: Pseudomonas sp. RU47
0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
B0 B1 B2 B3 B4
Mic
ro-n
utrie
nts
conc
entr
atio
ns in
mg
/ pla
nt s
hoot
dr
y m
atte
r
Treatments
MnFeZn
Analysis of micro-nutrients in maize plant shoot
a ab bcc
a
a
a
aa
aab
bc cd
The accumulation of the Zn in the shoot dry matter increased significantly
by inoculation of biostimulants
The application of all bacterial biostimulans tended to increase Fe accumulation
The application of B3, B4 and B1 increased significantly the accumulation of Mn.
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Significantly higher relative abundance of Gammaproteobacteria, Alphaproteobacteria and Bacteroidetes (Cytophagia and Sphingobacteria) in maize rhizosphere microbiomes was observed
The relative abundance of Actinobacteria, Firmicutes (Clostridia and Bacilli), Gemmatimonadetes, Planctomycetes and Nitrospira was higher in the bulk soil.
Principal component analysis (PCA) of the prokaryotic communities in maize rhizosphere and bulk soil
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Taxonomic distribution of the sequences belonging to OTUs significantly promoted by each BEs at each week.
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Summary
High rhizosphere competence correlated with plant growth promotion
Biostimulants increased plant growth and nutrient accumulation
Time dependent changes of the rhizosphere microbiome composition farmore pronounced than the microbiome shifts caused by the inoculatedbiostimulants
Complex and dynamic rhizosphere microbiome shifts were biostimulantstrain and growth stage dependent
High application potential for a bio-based agriculture in particular in soilwith reduced P-fertilization
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Soil type, plant species, plant growth stage; the cultivar might influence the plant microbiome but also the ecology of the inoculants and pathogens
The plant and its microbiome in the rhizosphere
PGPR/antagonist Pathogen
The mode of action of microbial inoculants
Inoculants act through several modes of action
Inoculants interact with the plant, its microbiome and the pathopogens through: phytohormons, nutrients; induced resistance but they cause also shifts of the indigenous microbiome through antibiotics, QS, VOCs or enzymes
www.julius-kuehn.deAG Smalla & guests 21 June 2017
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Control ARD
The soil and itsmicrobiome matter!!!
Thanks to the teams involvedin the projects!
Thanks you for your attention!