fall data reveals significant variation for permanganate...
TRANSCRIPT
ANOVA, p < 0.0370
• Variation likely due to grower management practices as there is not trend by crop type
• Several sites are below 500 ppm active carbon which may indicate a constraint on the production system
Grower Driven Rotations and On-Farm Test
Fall data reveals significant variation for permanganate oxidizable carbon (POXC)
Nematode Collection Methods
Top 0-6 inches
Bottom 6-12 inches
Mix
Mix
Extract nematodes from soil
Count by size• Small- bacterial feeders• Large- pathogenic
Baermann funnel
Bottom
Significant variation for total nematode counts
• Significant variation in nematode numbers by crop type.• Barley increases nematode numbers—in both depths
Spring Fall
Top
Spring Fall
• Small and large nematodes increase on barley• Large nematodes increase across all the crops but more so in Barley
Small and large nematodes are increased in barely
Top Bottom Top Bottom
Top 0-6 inches
Bottom 6-12 inches
Mix
Mix
Extract Microbe DNA
Barcoded ampliconsequencing
• ITS2 - Fungi•V4 - Bacteria•18s - Nematodes
Characterizing changes in microbial communities
Sequencing depth and core microbial communities – Spring 2017
• Average depth 10,000x• 517 OTUs• 217 - core community
distributed across most fields
Bacterial communities
• Average depth 15,000x• 278 OTUs• 149 - core community
distributed across most fields
Fungal Communities
OTU – operational taxonomic unit
Significant difference between top and bottom soils for both bacterial and fungal communities
Non-metric multidimensional scaling (NMDS)
Circles represent the 95% confidence
intervals within a group. Objects that are
more similar to one another are ordinated
closer together.
Fungal Communities
Bacterial Communities
Stress = 0.012
Stress = 0.005
Similarity among
bacterial communities
in top soils
Bacterial Communities – Top Soils
Stress = 0.015
Clustering by cover crop
among fungal communities
in top soils
Fungal Communities – Top Soils
Stress = 0.014
Some clustering by
cover crop among
bacterial communities in
bottom soils
Bacterial Communities – Bottom Soils
Stress = 0.009
Clustering among fungalcommunities
in bottom soils
Fungal Communities – Bottom Soils
Stress = 0.018
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B B B B T T T T
Fusarium
Alternaria
Colletotrichum
Leptosphaeria
Verticillium
Alternaria (Early Blight)
Fusarium (Dry Rot)
Collectotrichum(Black Dot)
Verticillium (Wilt)
Leptosphaeria(Blackleg)
Top Soils
Pathogenic Fungi
Bottom Soils Top Soils
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Beneficial Fungi
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B B B B T T T T
Mortierella
Tetracladium
Arthrobotrys
Penicillium
Mortierella
Tetracladium
Arthrobotrys Top SoilsBottom Soils Top Soils
Nu
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Significant differences in communities
Cover crop comparison - FungiDf Variance F Pr(>F)
crop 3 0.0563 8.7217 0.001 depth 1 0.0328 15.1266 0.001 crop:depth 3 0.0173 2.6650 0.001Residual 181 0.39262
Cover crop/grower - FungiDf Variance F Pr(>F)
plot 9 0.1421 9.2373 0.001depth 1 0.0328 19.1964 0.001plot:depth 9 0.0356 2.3175 0.001Residual 169 0.288928
Cover crop/grower - BacteriaDf Variance F Pr(>F)
field 9 0.06893 6.8853 0.001depth 1 0.04506 40.5329 0.001field:depth 9 0.02357 2.3561 0.001Residual 170 0.18902
Cover crop comparison - BacteriaDf Variance F Pr(>F)
crop 3 0.02359 5.8050 0.001depth 1 0.04506 33.2600 0.001depth:field 3 0.01128 2.7768 0.001Residual 182 0.24662
Permutation based multivariate analysis of Anova (MANOVA)
Differences in microbial communities driven by both grower field and cover crop
Next steps:
• Make comparisons between years (within a field)– Waiting for data for Fall (2017), will collect (Fall 2018)
• Analyze nematode genetic soil data, along with nematode count data– Waiting for data Spring and Fall (2017), will collect
• Examine pathogen pressure over time/change in cover crop
Summary and Take Homes
1. Interesting trends on yield and rotational crops
2. Rich fertility data with lots of leads to begin to follow
up
3. Nematodes increased on barley and likely pathogenic
to barley as well
4. Cover crops change the microbial community
composition and will change through time
Grower Input and Questions
Special thanks to:Jim Ehrlich
Potato Research Board
Kristen OttoJorge Ibarra