Research Updates on Sclerotinia Stem Rot Sudden Death Syndrome andRot, Sudden Death Syndrome, and 

Soybean Pathogen Detection

Glen Hartman, USDA-ARS, Department of Crop SciencesDepartment of Crop SciencesUniversity of Illinois

Funding provided by the Illinois Soybean AssociationFunding provided by the Illinois Soybean Associationfor the Soybean Disease & Insect Pests (SDIP)

Weather Conditions Drive DiseasesWeather Conditions Drive DiseasesPalmer Drought Severity Index (PDSI):

Ch l R t S l ti i St R tCharcoal Rot Sclerotinia Stem Rot

National Oceanic and Atmospheric

1929 to 2009

Administration (NOAA) National Climatic Data Center

Sclerotinia Stem RotPrevious Results (15 refereed publications since 1998)

Epidemiology/Field Management (7)Cl t d Fi ld

p gy g ( )Hartman, G.L., L. Kull, and Y.H. Huang. 1998. Occurrence of Sclerotiniasclerotiorum in soybean fields in East-Central Illinois and enumeration of inocula in soybean seed lots. Plant Disease 82:560-564.

Resistance (8)

Clustered Field Distribution of SSR

Resistance (8)Diers, B.W., F.J. Kopisch-Obuch, D.D. Hoffman, G.L. Hartman, W.L. Pedersen, C.R. Grau, and D. Wang. 2006. Registration of AxN-1-55 soybean germplasm with partial resistance to Sclerotinia stem rot. Crop Science 46:1403-1404.

Vuong, T., B.W. Diers, and G.L. Hartman. 2008. Identification of QTL for resistance to Slerotinia stem rot (Sclerotinia sclerotiorum) in plant introduction 194639. Crop Science 48:2209-2214.

Current Projects

The Use of Foliar Fungicides to Control Sclerotinia Stem Rot (Bradley)

Identification of Novel Loci for Partial Resistance to SclerotiniaStem Rot In Perennial Soybean Accessions (Domier)Stem Rot In Perennial Soybean Accessions (Domier)

2009 2009 –– DeKalbDeKalb SclerotiniaSclerotinia Fungicide Fungicide TrialTrialI id I id

Treatment

Incidence (%)

8-11-09

Incidence (%)

9-14-09Yield (bu/A)

Untreated 75 95 24Untreated 75 95 24Topsin M 4.5 FL @ 20 fl oz 43 96 24Proline @ 3 fl oz 38 95 24Headline 6 fl oz 73 100 22Domark 5 fl oz 68 98 23Quadris 6 fl oz 63 99 24Stratego 10 fl oz 35 98 23Cobra @ 12.5 fl oz + 1 pt COC 15 51 42Endura @ 8 oz (2x) 38 86 39

All sprayed at R1 (July 20) and Endura was sprayed again 9 days

Endura @ 8 oz (2x) 38 86 39LSD 0.05 33 15 8

All sprayed at R1 (July 20), and Endura was sprayed again 9 days later. Inoculated with the fungus on July 21.

Sudden Death SyndromePrevious Results (23 refereed publications since 1995)

Epidemiology/ManagementHartman, G.L., G.R. Noel, and L.E. Gray. 1995. Occurrence of soybean sudden death syndrome in East-Central Illinois and associated yield losses. Plant Disease 79:314-318.

Pathogen StudiesPathogen StudiesLi, S., G.L. Hartman, and Y. Chen. 2009. Evaluation of aggressiveness of Fusarium virguliforme isolates that cause sudden death syndrome. Journal of Plant Pathology 91:77-86.

Resistancees sta ceHartman, G.L., Y.H. Huang, R.L. Nelson, and G.R. Noel. 1997. Germplasmevaluation of Glycine max for resistance to Fusarium solani, the causal organism of sudden death syndrome. Plant Disease 81:515-518.

Farias Neto, A.F., R. Hashmi, M. Schmidt, S.R. Carlson, G.L. Hartman, S. Li, R.L. N l d B W Di 2007 M i d fi ti f dd d thNelson, and B.W. Diers. 2007. Mapping and confirmation of a new sudden death syndrome resistance QTL on linkage group D2 from the soybean genotypes PI 567374 and 'Ripley'. Molecular Plant Breeding 20:53-62.

Current ProjectsSeed Treatment Evaluations (Bradley)

Evaluation of Field Inoculation Methods (Bowen & Hartman)

Seed Treatment EvaluationJafe Weems M S Student (UIUC) Glen Hartman (USDA-ARS & UI)Jafe Weems, M.S. Student (UIUC)Carl Bradley, Adviser (UIUC)

Glen Hartman (USDA ARS & UI)Jim Haudenshield (USDA-ARS)Jason Bond (SIU)

Objective: Determine if fungicide seed treatments reduce SDS

Field Study (2008 and 2009)• 2 locations each year central and southern IL

j g

• 2 locations each year – central and southern IL • 2 soybean cultivars - susceptible and partially resistant• 12 fungicide seed treatments - 9 active ingredients, gmultiple combinations• Data collected - stand, root analysis (Win-Rhizo root scanning), fungal DNA in roots (qPCR), disease ratings, and yield

Greenhouse Study • Same treatments as field study• Same treatments as field study

Fungicide Seed Treatment ListAllegiance – metalaxyl

Apron XL – mefenoxam

1 - untreated control

2 - mefenoxam p

Maxim – fludioxonil

SoyGard – metalaxyl &

3 - fludioxonil, mefenoxam

4 - azoxystrobin, mefenoxam

5 - fludioxonil, azoxystrobin, mefenoxamazoxystrobin

YieldShield – Bacillus pumilus

5 fludioxonil, azoxystrobin, mefenoxam

6 - trifloxystrobin + metalaxyl

7 - prothioconazole, trifloxystrobin

8 thi l t ifl t bi t l l8 - prothioconazole, trifloxystrobin, metalaxyl9 - prothioconazole, trifloxystrobin +

metalaxyl, Bacillus pumilus GB3410 - thiophanate-methyl, mefenoxamp y ,11 - pyraclostrobin + thiophanate- methyl,

metalaxyl12 - thiophanate-methyl, azoxystrobin, Bacillus

pulmilus GB34 prothioconazolepulmilus GB34, prothioconazole, fludioxonil, mefenoxam

Field ResultsSeed treatments had very little effect on final SDS severity

2008 –southern IL locationL t di t i th t t d t l f l t l t (• Larger average root diameter in the untreated control - fewer lateral roots (more lateral roots would decrease average root diameter)

• Decreased number of root tips in untreated control - lower root tips counts means less branching and root development.

Average Root Diameter

0.940.96

Unt. Control

0.88

0.90.92

met

er (m

m)

Not significantlydifferent thancontrol

0.820.84

0.86

Dia

m controlSignifacantlydifferent thancontrol

1 2 3 4 5 6 7 8 9 10 11 12Seed Treatments

Greenhouse ResultsSeed treatment significant effects:

• Amount of F. virguliforme DNA present in root tissue - differences are statistically significant but cannot say it is of biological importancestatistically significant, but cannot say it is of biological importance

• Amount of root lesions/discoloration

Evaluation of Field Inoculation MethodsEvaluation of Field Inoculation Methods

Goal: Identify effective andefficient field inoculation methods to provide uniformity in characterizing soybeanin characterizing soybean lines for resistance

Roger Bowen (USDA-ARS)Glen Hartman (USDA-ARS & UI)Tara Slaminko (UI)Ji H d hi ld (USDA ARS)Jim Haudenshield (USDA-ARS)

Field Set Up for Two Experiments

Irrigation Study (2009) - Urbana, IL4 susceptible and 4 partially resistant cultivars• 4 susceptible and 4 partially resistant cultivars

• 4 Early MG3 - 4 Late MG 3

• 7 irrigation treatments

TimingIrrig. Treatments

Date Stage Irrigation1 2 3 4 5 6 0

1 X X X 6/21-7/13 V-R1 3.63”2 X X X X 7/14-7/27 R1-2 3.24”3 X X X 7/28-8/16 R4-5 4.02”

Inoculation Study (2009) - Urbana, IL-None - With Seed (35ml/5.5m) -With Seed High (70 ml/5.5 m)None With Seed (35ml/5.5m) With Seed High (70 ml/5.5 m)

-Trench Low (17.5 ml/5.5 m) -Trench (35 ml/5.5 m) -Trench High (70 ml/5.5 m)

Irrigation Results

Most SDS Symptoms in plots irrigated all timings or last 2 timingsSDS related to lower seed weight and yield (loss of 0.3 bu/ DX)g y ( )

30

35

40

ore

Irr. Trt x Cultivar Early CV's

050

60

Yield vs. Final Dx ScoreIrrigation Treatment Means – Early CVs

15

20

25

S D

X Sc

o 1 234

56

30

40

Yield (bu/A)

0

5

10SDS

y = ‐0.32x + 48.9R² = 0.89

0

10

20

LSD (0.05) =5.6

00 1 2 3 4 5 6

Irrigation Treatment0.0 10.0 20.0 30.0 40.0

SDS Dx Score 9/1

Inoculation Results- Highest SDS DX Score in ‘High Trench’ treatment- Inoculum with seed treatments resulted in lower stand counts- SDS related to lower yield

LSD (0.05) DX=4.5

Yield =2.4 Bu/A

Molecular Assays To Explore Pathogen Population Dynamics & Interactions: Jim Haudenshield and Glen Hartman

Multiplexed Analysis Increases Efficiency and Throughput

Benefits of Molecular Assaysy

• Faster & more efficient results

• In use for resistance evaluation, forensic detection, fungicide evaluation basic researchevaluation, basic research questions; potential for crop biosafety, sanitation

• Produce validated suites of assays (SOPs) for distribution to research & diagnostic labs

• Increase understanding of pathogen interactions for improved disease management

Thank YouThank You