Biological Control of Scab: How Close Are We to Reality?How Close Are We to Reality?

Gary Y. YuenGary Y. YuenDepartment of Plant Pathology

U i it f N b kUniversity of Nebraska

Biocontrol Researchers & AgentsBiocontrol Researchers & Agents

Researcher Organism Mechanism

G. Bergstrom Bacillus TrigoCor1448 iturin, surfactinsCornell Univ.

. Bleakley, Bacillus 1BA iturin, surfactinsS Dakota St US. Dakota St.U.

. Schisler, Cryptococcus OH182.9 niche competitionNCAURNCAUR

G. Yuen, Lysobacter C3 induced resistanceyU. Nebraska dihydromaltophilin

Lab to Field ResearchLab to Field ResearchIsolationropagation

EfficacyDosage

FHB SeverityDON

p gormulation

DosageTiming

DONYield

Performance of Lysobacter C3 in 13 G h E i t

100

Greenhouse Experiments

ets

80Water controlC3 treated

ed s

pikl

e

60

% in

fect

e

40

%

20

1 2 3 4 5 6 7 8 9 10 11 12 130

ntrol of Fusarium head blight in spring wheat ith L b t C3with Lysobacter enzymogenes C3

C3 + tebuconazole @ anthesis

Tebuconazole @ anthesis C

D

C3 @ head emergence

B

BC

C3 @ anthesis

Control A

B

0 10 20 30 40 50 60 70Percent infected spikelets

Uniform Biological Control Trials 2004-2008

ND (2008)HRSW

AR E MilusSD

HRSW, barley

NE

AR - E. Milus

MO - L. Sweets

MOSRWW

HRWW NE - G. Yuen, C. Jochum

ND – S HalleyAR

(2004)SRWW

ND – S. Halley

SD – B. BleakleyM. DraperK. Ruden

Uniform Biological Control TrialsUniform Biological Control Trials• Objectives:

Identify most effective biocontrol agent/product– Identify most effective biocontrol agent/product – Integrate biological and chemical strategies

• Standardized treatments

• Standardized methodologygy– Dosage, application method– Plot size, inoculation and misting

Disease yield DON data– Disease, yield, DON data– Microbe propagation, handling, population

measurement

• Results reported in Natl’ FHB Forum Proc

FHB Averaged Across 5 Trials 2005

40

45

50¤ significantly different

from control¤ ¤¤

%

30

35

40Control

Folicur¤

¤

20

25

30Bacillus1BA

1BA+Folicur

10

151BA+Folicur

LysobacterC3

C3 F li

¤ ¤ ¤¤

0

5

Incidence Severity Index

C3+Folicur

Incidence Severity Index

FHB Averaged Across 6 Trials 200760%

50

60

¤ significantly differentfrom control¤

%

40Control

Prosaro

1BA

¤¤

¤¤

20

301BA

1BA+Prosaro

TrigoCor1448¤¤

¤ ¤¤

10

20TrigoCor+Prosaro

C3¤ ¤¤

¤¤

¤

0Incidence Severity Index

C3+Prosaro

Incidence Severity Index

DON Averaged Across 3 Trials 2007

3 5

4 ppm

3

3.5Control

Prosaro

¤

2

2.5 1BA1BA+Prosaro

TrigoCor1448

¤ ¤ ¤ ¤

1

1.5g

TrigoCor+Prosaro

C3

C3 P

0

0.5C3+Prosaro

¤ significantly different from control

DON in MO & Averaged Across 7 Trials 2008

10

12ppm

¤ ¤ significantly differentnificantly different

8

10Control

Prosaro

¤

¤ ¤

from Prosarom control

61BA

1BA+Prosaro

TrigoCor1448

¤ ¤

2

4TrigoCor1448

TrigoCor+Prosaro

Taegro

0

2 Taegro+Prosaro¤ ¤0.5

O 'Roane' MO 'Elkhart' 7 exptsTreatment effects were

Summary of Findings From Uniform Biological Control Trials 2004-2008Biological Control Trials 2004 2008

Biocontrol agents can be as effective in controlling FHB as a fungicide in individual trialsas a fungicide in individual trials– No agent is consistently effective across trials.

Bi t l t f i id bi ti idBiocontrol agent-fungicide combinations can provide better reduction of DON than a fungicide in individual trials

Benefits of combinations do not appear across trials– Benefits of combinations do not appear across trials

Integration of biological agents or biocontrol agent-f i id bi ti ith h t i t dfungicide combinations with host resistance deserves more thorough investigation

Need for further development of biological strategies still exists

Ongoing Research to Improve Biocontrol

Use of biocontrol agents to control late infectionsS tt H ll NDSU- Scott Halley, NDSU

Ongoing Research to Improve Biocontrol

Propagation and formulation technology

Poster #18“Physiological Profiling and Carbon Source Utilization of

Four Bacillus Strains Used as Biological Control Agents of FHB”

Morgan and BleakleyMorgan and Bleakley

Ongoing Research to Improve BiocontrolPropagation and formulation technology– Enhance survival of yeast biocontrol agents using

cold adaptation (D Schisler USDA ARS NCUAR)cold adaptation (D. Schisler, USDA ARS NCUAR)

Slide providedSlide provided by D. Schisler

Ongoing Research to Improve BiocontrolOngoing Research to Improve BiocontrolCompatibility with commercial application technology

(Yuen et al 2007)(Yuen et al. 2007)

TankTank12 gal

Nozzle XR8002

Cast iron gear drive centrifugal pump (HYPRO

Pre-filter sampling

hose Post filter sampling

hosep p (Model 9006C-O)

hose

Filter

Compatibility with commercial application technology

50

60

70

CFU/ml

107

108

109

1010

quid volume oC

20

30

40

OH71.41BA C3

101

102

103

104

105

106

C3 OH71.4 1BAC

10 gallonsquid volumemixing tank:

Minutes

0 10 20 30 40 50 6010

Minutes

0 10 20 30 40 50 60

101

CFU/ml

oC 40

50

60

70

OH71.41BA C3

CFU/ml

106

107

108

109

1010

0 10 20 30 40 50 6010

20

30

40

0 10 20 30 40 50 60

101

102

103

104

105

C3 OH71.4 1BAC

100 gallons

Minutes

0 10 20 30 40 50 60

Minutes

0 10 20 30 40 50 60

Compatibility with commercial application technology

Foaming in suspension of Bacillus 1BA

Ongoing Research to Improve Biocontrol• Combinations of biocontrol agents

OH 182.9

OH 71.4

Two co-fermented yeast antagonists cultured a melezitose medium that differentiates strains based on growth rates

Research to Improve Biocontrol

Host and environmental constraints on biocontrol agent populations and expression of biocontrol mechanisms

82002 Ingot

Lysobacter enzymogenes C3 populations on wheat heads

U/g

6

7 2002 Russ 2003 Ingot 2003 Russ

Log 1

0 CFU

4

5

2

3

Days after treatment

0 1 2 3 4 5 6 7

Research to Improve BiocontrolHost and environmental constraints on biocontrol agent populationsHost and environmental constraints on biocontrol agent populations and expression of biocontrol mechanisms

1 0 0Susceptible to mod susceptible Mod resistant toS tibl t d t l tibl

Efficacy of Lysobacter enzymogenes C3 in controlling FHB is host genotype dependent

6 0

8 0

C 3C o n tro l

Susceptible to mod. susceptible Mod. resistant to resistant

* Sign. @ P≤0.05Susceptible to moderately susceptible Moderately resistant

to resistant

2 0

4 0

C o n tro l

**

* *0

0

obwh

ite

Norm

Oxen

Russ

Whe

aton

Alse

n

Ingo

tND

2710

* * *

Bo

N O

Wh A I ND

Hard red spring wheat cultivars

Research to Improve Biocontrol

Host and environmental constraints on biocontrol agent populations and expression of biocontrol mechanismsp p p

oster #11“E l f B ill btili Wh t Fl t i R l ti“Ecology of Bacillus subtilis on Wheat Florets in Relation to Biological Control of FHB/DON”Kawamoto et al.

oster #19“U f M t P b bl N b d PCR M th d t“Use of Most Probable Number and PCR Methods to Estimate Populations of Bacillus Strain 1BA Applied to Wheat and Barley for Biological Control of FHB”Morgan and Bleakley

Thinking outside the boxThinking outside the box

Microbes that can degrade DON or inhibit DONMicrobes that can degrade DON or inhibit DON formation

Engineer endophytic microbes to express antifungal compounds, DON inhibitors, DONantifungal compounds, DON inhibitors, DON degrading enzymes in plant tissues

Apply antagonists to crop debris or stimulate resident microbes to inhibit Fusarium sporulationp

ThanksThanksUSWBSI Gary BergstromBruce BleakleyDavid SchislerScott HalleyLaura SweetsAll support staff Colleagues in scab/DON

research