disease suppressive soil has both diverse and uniform ecology : modeling and characterization
TRANSCRIPT
Disease suppressive soil has both diverse and uniform ecology : Modeling and characterizationY-h. Taguchi, Chuo University,
Kazunari Yokoyama, NARO
sector 1disease rate19.2%
sector 3disease rate100%
sector 2disease rate69.2%
0. Introduction (so far, long hostory over more than 20 years ...)
replant failure
No cultivations without disinfect
Soil Sample
dilute suspension agar plate
culture
random sampled colony to biolog plate
Step A
step C
Step B
Cluster Analysis
digitized carbon resource consumption abilityplate reader
Experimental procedure of biodiversity index method for soil bacteria
GN MicroPlateBasically, carbon resources
Appearance of biolog plate coloring
This bacteria consumethis carbon resources
Bacteria 1 Bacteria 2
Bacteria 3 Bacteria 4
bacteria A
B
C
D
Adistance - B
distance AB -C
distance ABC -D
Colony method
biodiversity independent of taxon =
Squared total cluster distance / number of bacteria
Estimation of biodiversity by biolog plate
(Yokoyama 1992)
Soil bacteria is isolated by diluted plate method and 95 carbon resources consumption ability is used for the estimation of biodiversity
bacteria
bacteria
bacteria
Many kinds of species are in suppressive soil
多様性指数
replant failure(%)
An example of spinach repeat failure (Hida, Gifu)
bio
dive
rsity inde
x
soil sample
dilute suspension dilute suspension to
biolog plate
ステップC有機物分解能を数
値化プレートリーダー
Experimental Procedure of soil bacteria biodiversity/activity measurement
Skip
low biologically activity soil High biologically activity soil
Carbon resource consumption rates in soil are measured over 48 hours
OmniLog Robot eye automatically measure carbon resources consumption rate and put into data base
Cottony Leak of Scarlet Runner Bean (Phaseolus coccineus:ベニバナインゲン)
and soil bacteria biodiversity/activity
Sector 1 Sector 2 Sector 3
disease rate(%) 19.2 69.2 100
soil bacteria biodiversity/activity(*)
1,114,100 412,000 306,097
sector 1disease rate19.2%
sector 3disease rate100%
sector 2disease rate69.2%
Katakura Chikkarin CO. LTD, Tsukuba Research Institute Co.,Ltd. 、 Agricultural Research I nstitute, I baraki Agricultural Center, DGC Technology Inc.
Cottony Leak, which causes repeat failure, can be suppressive by the soil with high biodiversity/activity
10
(*) Integration of time development
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1.Model
Assumptions
Carbonresource A
Carbonresource B
TimeSoil
bacteriaconsume
Rapidly consumedcarbon resources
are consumed by more kinds of soil bacteria ⇔
Slowly consumedcarbon resources
are consumed by less kinds of soil bacteria ⇔
Co
nsum
ptio
n
Creator:LibreOffice 3.3 LanguageLevel:2
Carbon resources vs Soil Bacteria : Interaction Matrix
Carbon Resources
Interactive region
The i1 th species soil
bacteria consumes carbon resource j
1
The i 2th species soil
bacteria does not consume carbon resource j
2
# of carbon resources consumed by at least a bacteria
Soil Ba
cteria
Model :Lotka-Volterra type
d x i
d t =(Σ j=1
M0
Niy j )x i
d y j
d t=−(Σ
i= NM0
j
N x i)y j , j⩽M0
0, j> M0
xi : Population of the i th species bacteria
yj: The amount of unconsumed j th carbon resources
Initial condition:xi=0,yj=1 -ε 、(ε:random number、0 < ε < 0.1)M(# of kinds of carbon resources)90N(# of species of soil bacrteria)90M
0=20
M0=40
M0=80
Title:(fig1a.eps) Creator:(ImageMagick) CreationDate:(2011-11-25T15:50:48+09:00) LanguageLevel:1
Title:(fig1b.eps) Creator:(ImageMagick) CreationDate:(2011-11-25T15:50:53+09:00) LanguageLevel:1
Title:(fig1c.eps) Creator:(ImageMagick) CreationDate:(2011-11-13T14:00:59+09:00) LanguageLevel:1
M0=20 M
0=40 M
0=80
diseaserate:100%
disease rate:69.2%
diseaserate:19.2%
Sick Healthy
Actual measurement (?) of disease supressive soil (carbon resources consumption rate of each soil bacteria: colonized and isolated well )
Carbon Resource ID
Soil b
acte
ria ID
Conclusion・We have developed a model reproducing carbon resource consumption rate time development of soil bacteria. ・Disease suppression is suggested to be enabled bu diverse carbon resources consumption rates. ・It does not disagree with the actual measurements of interaction matrix.
Furthermore.. (omitted, see the next slide) ・ nMDS embedding exhibits that homogeneity
and uniformity of time development are important for disease suppressive soil.
△disease rate:100%+disease rate:69.2%◯disease rate :19.2%☓compost
specialists(specialized to a few carbon resources)
generalist (not specialized)
specialist > generalist
specialist = generalist
specialist <generalist
points=carbon resources
Collaborator wanted!