Soybean seed treatment fungicide to protect stand and optimize profit
Advancing Agricultural Performance® and Environmental Stewardship
February 19, 2015 Ames, Iowa
Soybean seed treatment fungicide to protect stand and optimize profit ALISON ROBERTSON Iowa State University [email protected]
Funded in part by the soybean checkoff
Soybean production costs in Iowa
Iowa Farm Business Association
Pathogens that decrease stand
Pioneer.com
Pythium species
Phytophthora sojae
Rhizoctonia solani
Fusarium species
Soybean seedling disease survey 2011-2013
n = 2400
•
82 oomycetes species
•
13 species reported as known pathogens
•
Species frequency fluctuated between years
M. Chilvers, Michigan State U.
n = 1100
1 Aphanomyces spp.
4 Phytopythium spp.
2 Phytopythium spp.
7 Phytophthora spp.
3 Phytophthora spp.
57 Pythium spp.
52 Pythium spp.
Pythium species in Iowa Soybean
Corn
Pythium oopapillum Pythium aff. dissotocum Pythium lutarium Pythium aff. torulosum Pythium nodosum Pythium sylvaticum Pythium perplexum Pythium coloratum Pythium pachycaule Pythium irregulare Pythium ultimum var. ultimum Pythium sp. Pythium attrantheridium Pythium heterothallicum Phytophthora sojae Pythium ultimum Pythium pleroticum Pythium inflatum Pythium hypogynum Pythium aff. dictyosporum
0.00
20.00
40.00
60.00
Soybean seedling disease survey 2011-2013 Rhizoctonia Trichoderma 9% 1% Mortierella
Other 4%
2%
Alternaria 2% Bionectria 4%
Hypocrea 6%
F. verticillioides 9%
3000 isolates
Fusarium 72%
F. sporotrichioides 6%
F. acuminatum 12%
F. commune 4%
F. solani 11% F. proliferatum 4%
Ahmad Fakoury, Southern Illinois
Other 2% F. avenaceum 2%
F. oxysporum 37%
F. graminearum 13%
Fusarium species in Iowa
Diaz-Arias, et al., 2013. Plant Dis.97:1157
Crikey! What does that all mean?
Pathogenicity: seed rot
55, 64 & 73F
Pathogen + Seed
Pathogenicity: damping off
check
inoculated
55, 64 & 73F
Disease severity index
Pythium: some like it hot; some like it cool 55F 72F
Not all species cause disease Temperature affects disease severity
Martin Chilvers, Michigan State U.
Pythium species in Iowa * * * *
Soybean
Corn
Pythium oopapillum Pythium aff. dissotocum Pythium lutarium Pythium aff. torulosum Pythium nodosum Pythium sylvaticum Pythium perplexum Pythium coloratum Pythium pachycaule Pythium irregulare Pythium ultimum var. ultimum Pythium sp. Pythium attrantheridium Pythium heterothallicum Phytophthora sojae Pythium ultimum Pythium pleroticum Pythium inflatum Pythium hypogynum Pythium aff. dictyosporum
0.00
* * *
20.00
40.00
60.00
P. lutarium P. oopapillium P. sylvaticum P. torulosum
Temperature and pathogenicity 55 F
64 F
73 F
Root rot severity (%)
P. lutarium
P. oopapillum
P. sylvaticum
P. torulosum Matthiesen and Robertson (submitted)
Pythium: some like it hot; some like it cool 55 F
64 F
73 F
Root rot severity (%)
P. lutarium
P. oopapillum
P. sylvaticum
P. torulosum Matthiesen and Robertson (submitted)
Soybean seed treatment estimates
% of acres
90 80
3-way
70
Fungicide-Insecticide
60
Fungicide only
50 40 30 20 10 0 1996 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Data from Syngenta Seed Care
Seed treatments for Pythium & Phytophthora sojae Active ingredient
Example of Product
mefenoxam/m Apron®XL/Alle etalaxyl gience® FL ethaboxam azoxystrobin
Dynasty®
pyraclostrobin
Stamina®
trifloxystrobin
Trilex® Flowable
Chemical group
FRAC group
Phenyl amides
4
G-E
G-E
Thiazole carboximide
U5
E
G-E
-
P
-
P
-
P
QoI (Strobilurins)
11
Phytophthora Pythium sojae species
E = excellent; G = good; F = fair; P = poor; N = none
Seed treatments for fungi Active ingredient
Example of Product
Chemical group
FRAC group
Fusarium species
Rhizoctonia solani
fludioxonil
Maxim® 4FS
PhenylPyrrols
12
G-E
G
sedaxane
Vibrance®
-
penflufen
EverGolTM (PPST)
-
SDHI
fluxapyroxad
Xenium® (Acceleron)
fluopyram
ILeVO
azoxystrobin pyraclostrobin trifloxystrobin
Dynasty® Stamina® Trilex®
QoI (Strobilurins)
ipconazole
Rancona®
DMI (Triazole)
7
E
E (SDS)
-
11
F
F
3
G-E
G
Sensitivity to fungicides varies amongst species
Broders et al., 2007
Determining fungicide sensitivity a
b
c
d
0 ppm
Media + fungicide at different concentrations
1 ppm
Pythium placed at edge of Petri dishes
10 ppm
Growth measured 24, 48 and 72h
100 ppm
Evaluated at 3 temperatures: 55F, 64F, 73F
Determining fungicide sensitivity a
b
c
d
0 ppm
1 ppm
10 ppm
100 ppm
Calculate EC50 = Concentration at which growth of Pythium is reduced by 50%
Compare EC50 at each temperature for each species
Sensitivity to fungicides varies amongst species Maxim®
Munkvold, unpub.
Sensitivity to fungicides varies amongst species Rancona® Maxim®
Munkvold, unpub.
Sensitivity to fungicides varies amongst species
Temperature also affects fungicide sensitivity
Sensitivity to fungicides varies amongst species 10 9 8
A
55F
64F
73F
metalaxyl
EC50 (µg a.i./ml)
7 6
B
5
a
4 3 2 1
NS
0 P. lutarium
NS
C
b b
P. oopapillum P. sylvaticum P. torulosum
Sensitivity to fungicides varies amongst species azoxystrobin (Dynasty®)
25
A EC50 (µg a.i./ml)
20 15 10 5
a ab
b
AB
A AB
B
55F
a
64F
ab B
c
0 P. lutarium P. oopapillum P. sylvaticum P. torulosum
73F
Seed treatment trials, Iowa: 2011-2013
Seed treatment trials, Iowa: 2011-2013
Yield response (bu/A)
10 5 0 -5 -10 -15
Mean yield response = 0.32 bu/A; Frequency of positive yield response = 50%; Frequency yield response >2 bu/A = 35%
Small plot seed treatment trials 2014
Soil temperatures: >60F at NERF and SERF
February 19, 2015 Ames, Iowa
Soybean seed treatment fungicide to protect stand and optimize profit ALISON ROBERTSON Iowa State University [email protected]
Funded in part by the soybean checkoff
Soybean production costs in Iowa
Iowa Farm Business Association
Pathogens that decrease stand
Pioneer.com
Pythium species
Phytophthora sojae
Rhizoctonia solani
Fusarium species
Soybean seedling disease survey 2011-2013
n = 2400
•
82 oomycetes species
•
13 species reported as known pathogens
•
Species frequency fluctuated between years
M. Chilvers, Michigan State U.
n = 1100
1 Aphanomyces spp.
4 Phytopythium spp.
2 Phytopythium spp.
7 Phytophthora spp.
3 Phytophthora spp.
57 Pythium spp.
52 Pythium spp.
Pythium species in Iowa Soybean
Corn
Pythium oopapillum Pythium aff. dissotocum Pythium lutarium Pythium aff. torulosum Pythium nodosum Pythium sylvaticum Pythium perplexum Pythium coloratum Pythium pachycaule Pythium irregulare Pythium ultimum var. ultimum Pythium sp. Pythium attrantheridium Pythium heterothallicum Phytophthora sojae Pythium ultimum Pythium pleroticum Pythium inflatum Pythium hypogynum Pythium aff. dictyosporum
0.00
20.00
40.00
60.00
Soybean seedling disease survey 2011-2013 Rhizoctonia Trichoderma 9% 1% Mortierella
Other 4%
2%
Alternaria 2% Bionectria 4%
Hypocrea 6%
F. verticillioides 9%
3000 isolates
Fusarium 72%
F. sporotrichioides 6%
F. acuminatum 12%
F. commune 4%
F. solani 11% F. proliferatum 4%
Ahmad Fakoury, Southern Illinois
Other 2% F. avenaceum 2%
F. oxysporum 37%
F. graminearum 13%
Fusarium species in Iowa
Diaz-Arias, et al., 2013. Plant Dis.97:1157
Crikey! What does that all mean?
Pathogenicity: seed rot
55, 64 & 73F
Pathogen + Seed
Pathogenicity: damping off
check
inoculated
55, 64 & 73F
Disease severity index
Pythium: some like it hot; some like it cool 55F 72F
Not all species cause disease Temperature affects disease severity
Martin Chilvers, Michigan State U.
Pythium species in Iowa * * * *
Soybean
Corn
Pythium oopapillum Pythium aff. dissotocum Pythium lutarium Pythium aff. torulosum Pythium nodosum Pythium sylvaticum Pythium perplexum Pythium coloratum Pythium pachycaule Pythium irregulare Pythium ultimum var. ultimum Pythium sp. Pythium attrantheridium Pythium heterothallicum Phytophthora sojae Pythium ultimum Pythium pleroticum Pythium inflatum Pythium hypogynum Pythium aff. dictyosporum
0.00
* * *
20.00
40.00
60.00
P. lutarium P. oopapillium P. sylvaticum P. torulosum
Temperature and pathogenicity 55 F
64 F
73 F
Root rot severity (%)
P. lutarium
P. oopapillum
P. sylvaticum
P. torulosum Matthiesen and Robertson (submitted)
Pythium: some like it hot; some like it cool 55 F
64 F
73 F
Root rot severity (%)
P. lutarium
P. oopapillum
P. sylvaticum
P. torulosum Matthiesen and Robertson (submitted)
Soybean seed treatment estimates
% of acres
90 80
3-way
70
Fungicide-Insecticide
60
Fungicide only
50 40 30 20 10 0 1996 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Data from Syngenta Seed Care
Seed treatments for Pythium & Phytophthora sojae Active ingredient
Example of Product
mefenoxam/m Apron®XL/Alle etalaxyl gience® FL ethaboxam azoxystrobin
Dynasty®
pyraclostrobin
Stamina®
trifloxystrobin
Trilex® Flowable
Chemical group
FRAC group
Phenyl amides
4
G-E
G-E
Thiazole carboximide
U5
E
G-E
-
P
-
P
-
P
QoI (Strobilurins)
11
Phytophthora Pythium sojae species
E = excellent; G = good; F = fair; P = poor; N = none
Seed treatments for fungi Active ingredient
Example of Product
Chemical group
FRAC group
Fusarium species
Rhizoctonia solani
fludioxonil
Maxim® 4FS
PhenylPyrrols
12
G-E
G
sedaxane
Vibrance®
-
penflufen
EverGolTM (PPST)
-
SDHI
fluxapyroxad
Xenium® (Acceleron)
fluopyram
ILeVO
azoxystrobin pyraclostrobin trifloxystrobin
Dynasty® Stamina® Trilex®
QoI (Strobilurins)
ipconazole
Rancona®
DMI (Triazole)
7
E
E (SDS)
-
11
F
F
3
G-E
G
Sensitivity to fungicides varies amongst species
Broders et al., 2007
Determining fungicide sensitivity a
b
c
d
0 ppm
Media + fungicide at different concentrations
1 ppm
Pythium placed at edge of Petri dishes
10 ppm
Growth measured 24, 48 and 72h
100 ppm
Evaluated at 3 temperatures: 55F, 64F, 73F
Determining fungicide sensitivity a
b
c
d
0 ppm
1 ppm
10 ppm
100 ppm
Calculate EC50 = Concentration at which growth of Pythium is reduced by 50%
Compare EC50 at each temperature for each species
Sensitivity to fungicides varies amongst species Maxim®
Munkvold, unpub.
Sensitivity to fungicides varies amongst species Rancona® Maxim®
Munkvold, unpub.
Sensitivity to fungicides varies amongst species
Temperature also affects fungicide sensitivity
Sensitivity to fungicides varies amongst species 10 9 8
A
55F
64F
73F
metalaxyl
EC50 (µg a.i./ml)
7 6
B
5
a
4 3 2 1
NS
0 P. lutarium
NS
C
b b
P. oopapillum P. sylvaticum P. torulosum
Sensitivity to fungicides varies amongst species azoxystrobin (Dynasty®)
25
A EC50 (µg a.i./ml)
20 15 10 5
a ab
b
AB
A AB
B
55F
a
64F
ab B
c
0 P. lutarium P. oopapillum P. sylvaticum P. torulosum
73F
Seed treatment trials, Iowa: 2011-2013
Seed treatment trials, Iowa: 2011-2013
Yield response (bu/A)
10 5 0 -5 -10 -15
Mean yield response = 0.32 bu/A; Frequency of positive yield response = 50%; Frequency yield response >2 bu/A = 35%
Small plot seed treatment trials 2014
Soil temperatures: >60F at NERF and SERF
