Data and code from: Environment and plant genetics shape barley rhizosphere microbiome structure across contrasting locations
Data files
Aug 04, 2026 version files 14.32 MB
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Assembly_Processes.R
76.65 KB
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Combined_Phyloseq.Rmd
27.28 KB
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ps16S.RDS
11.68 MB
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psITS.RDS
2.16 MB
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README.md
3.92 KB
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sample_data.csv
359.03 KB
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varplot.R
2.55 KB
Abstract
Soil microorganisms are crucial for plant survival and productivity, but factors governing rhizosphere recruitment across diverse regions remain unclear. This study investigated the rhizosphere microbiome of barley, using elite cultivars across seven location-year trials to determine the effects of environmental factors and crop genotype on bacterial and fungal community composition. Three locations were in the US northern Great Plains, and Hawai’i was used as a contrasting environment. A greenhouse reciprocal transplant study determined the relative contributions of soil physicochemical factors and soil inoculum to rhizosphere community structure. Using 16S and ITS2 amplicon sequencing, the study characterized bacterial and fungal microbiomes and assessed the contribution of environment, soil chemistry, and barley genetics to microbial community assembly. In locations within the adapted range of barley, Actinobacteriota was the dominant phylum, while Proteobacteria was dominant in Hawai’i. Variance partitioning showed that 73% of bacterial and 80% of fungal genera were associated with location-year effects, while 53% of bacterial and 36% of fungal genera were responsive to soil factors. Enrichment analysis found 21.6% of bacterial and 51.4% of fungal ASVs were unique to specific barley genotypes. Results from the reciprocal transplant study validated field observations by demonstrating that 20.7% of the variation in community structure was explained by base soil while 18.2% was explained by inoculum source. These findings demonstrate that environmental variation is the dominant constraint on rhizosphere community composition but within these constraints, barley genotypes recruit distinct bacterial and fungal taxa.
Dataset DOI: 10.5061/dryad.jh9w0vtsf
Description of the data and file structure
This dataset contains the data and code required to replicate analyses in Killian et al (in review) evaluating the role of environmental factors and plant genetics in shaping the barley rhizosphere microbiome. Data are from a common garden experiment with 232 elite barley lines from the S2MET population grown over seven location years. A greenhouse reciprocal transplant study determined the relative contributions of soil physicochemical factors and soil inoculum to rhizosphere community structure. Genetic data consist of bacterial 16S rRNA V6-V8 and fungal ITS2 amplicon sequence reads. Barley agronomic data (Yield ,test weight, plum, protein, and biomass) are also included. The results demonstrated that environmental variation is the dominant constraint on rhizosphere community composition but within these constraints, barley genotypes recruit distinct bacterial and fungal taxa.
Note that "NA" in any data cell indicates missing data.
Files and variables
File: sample_data.csv
Description: Sample Data
Variables
- SampleID: Unique sample identifier
- Line: Barley genotype from the S2MET population
- Plot: numerical identifier for each plot
- Year: study year
- Location: BZ: Bozeman, MT, MO: Moccasin, MT, SD: South Dakota, HI: Hawai'i
- Block: Replicate number
- RhizoShootDryWt:
- HeadingDate: Day of year
- MaturityDate: Day of year
- PlantHeight: Average height of plants (units: cm)
- TillerNumber: Count of the average number of tillers per plant
- Biomass: Total crop above ground biomass (units: g)
- HarvestIndex: Ratio of grain yield to total biomass
- Yield: grain yield (units: kg/ha)
- TestWeight: grain test weight (units: g)
- Plump: Average barley grain plumps (%) for each sample
- Protein: grain protein content (%)
- GrainMoisture: grain moisture (%)
- locyr: Location-year
- pH: soil pH
- Nitrate: Soil nitrate (units ppm)
- OM: Soil Organic Matter (%)
- K: Soil potassium (units: ppm)
- Precip: Annual precipitation (units: mm)
- texture: Soil texture class (USDA soil classification)
- PrevCrop: Crop grown the previous growing season
- PrevCrop2yr: Crop grown 2 years prior
- PC1: First principal coordinate axis from hierarchical clustering of barley genotypes
- PC2: Second principal coordinate axis from hierarchical clustering of barley genotypes
- clust: Barley genotype cluster number
- Type: Rhizosphere or bulk soil sample type
File: ps16S.RDS
Description: Bacterial 16S sequencing data with ASV table, taxonomy table, and sample data in phyloseq format
File: psITS.RDS
Description: Fungal ITS sequencing data with ASV table, taxonomy table, and sample data in phyloseq format
Code/software
R Environment for Statistical Computing
Version: R 4.1.2
- phyloseq
- microeco
- file2meco
- ggplot
- ggpubr
- microViz
- dplyr
- tidyr
- magritter
- spaa
- phylosmith
- RColorBrewer
- patchwork
- variancePartition
- gt
- VennDiagram
- UpSetR
- multicomp
- multicomVier
- vegan
Combined_Phyloseq.Rmd
This file processes the phyloseq objects to generate figures 1 and 6 and supplemental tables. Requires the package "phyloseq" to be installed.
varplot.R
This file is a custom function to generate figure 2.
Assembly_Processes.R
This file contains the code to perform analysis for ecotype identification and assembly processes and generate figures 3 - 6.
Access information
Other publicly accessible locations of the data:
- The raw sequence data are deposited in the NCBI Sequence Read Archive (https://www.ncbi.nlm.nih.gov/bioproject/PRJNA909304)
