Managing Fusarium Head Blight in Irrigated Wheat

and Barley

Mary Burrows, William Grey, Alan Dyer and

Luther TalbertDept. Plant Sciences/Plant Pathology,

MSU

Fusarium head blight (scab)

• DON limit 1 ppm for human food; 2 ppm for feed

Symptoms at harvest• Diagnostic tan to

brown discoloration of stem below the head.

• Infected plant residue serves as in-field inoculum and contains DON.

Fusarium head blight in Montana

Sporadic disease

Map http://www.peninsulaflyfishers.org/Fishing_Tales/montanaSpring02/montana_map.gif

<2004

YR 2005, 2006

YR2007, 2009

YR2009

Dyer, 2008

Fusarium head scab: Should I be concerned?

• Do you have a history of scab? *Residue-borne*– Partially bleached heads– Pink kernels (moist chamber)– Tombstone kernels– Brown at base of head

• Fully or partially bleached heads?(root and crown diseases, drought, sawfly)

• Irrigation type• Tillage regime• Previous crop

Grey, 2006

Scab in barley vs. scab in wheat

• Barley flowers before head emergence; spray earlier

• 2-row barley less suceptible than 6-row barley (head architecture)

• No variety resistance is available

Grain “Tombstone Kernels”• Chalky appearance from the fungal mycelium.• Mycotoxins, including “Deoxynivalenol -2“• FDA advisory level, 1.0 ppm ‘DON’

(Courtesy A. Schilder and G. Bergstrom)

FHB tolerant and susceptible spring wheat varieties

Tolerant ‘Sumai3’ Varieties

• Alsen• Glenn• Freyr• MT0550• Knudson• Kelby• Granite• Volt

Susceptible Varieties

• Howard• MT0551• Vida• Explorer• Choteau• Expresso• Hank – Agronomic

preferred variety for Irrigated production

Grain Yield , Scab Nursery, Irrigated Spring Wheat

Tolerant‘Sumai3’ Bu/AC Susceptible Bu/Ac

ALSEN 71 HOWARD 66

GLENN 70 MT0551 67

FREYR 87 VIDA 70

MT0550 83 EXPLORER 54

KUNTZ 87 CHOTEAU 78

KNUDSON 83 EXPRESSO 77

KELBY 81 HANK 55

GRANITE 75

VOLT 87MEAN COMPARISON LSD = 5.8 p<0.05, 7 replicates, 2006 & 2007.

Grain Quality “Deoxynivalenol-2” detection limit 0.2 ppmNDSU Analytical Lab

Tolerant‘Sumai3’ ppm Susceptible ppm

ALSEN 0.11 HOWARD 1.08

GLENN 0.14 MT0551 1.33

FREYR 0.25 VIDA 1.41

MT0550 0.25 EXPLORER 2.11

KUNTZ 0.36 CHOTEAU 2.83

KNUDSON 0.36 EXPRESSO 3.30

KELBY 0.36 HANK 8.76

GRANITE 0.38

VOLT 0.43MEAN COMPARISON LSD = 1.01 p<0.05, 7 replicates, 2006 & 2007.

Scabby grain

Seed Quality, Germination Blotter Test %MSU Seed Analytical Lab

Tolerant‘Sumai3’ %Germ Susceptible %Germ

ALSEN 96 HOWARD 86

GLENN 94 MT0551 88

FREYR 88 VIDA 81

MT0550 95 EXPLORER 79

KUNTZ 91 CHOTEAU 76

KNUDSON 93 EXPRESSO 72

KELBY 89 HANK 55

GRANITE 91

VOLT 90MEAN COMPARISON LSD = 7.5 p<0.05, 7 replicates, 2006 & 2007.

Alsen, Resistant

Hank, Susceptible

Benefits of ‘Sumai3’ tolerance to FHB in spring wheat varieties

• Grain DON-2

• Disease Incidence

• Grain Yield

• Germination%

• 3.70 to 0.29 ppm• REDUCTION, 92%

• 28 to 8 % scab heads.• REDUCTION, 71%

• 66 TO 80 bu/ac• INCREASE, 22%

• 73% to 92%• INCREASE, 26%

Current efforts (Gray, Talbert, Dyer)• Improved semi-dwarf wheat varieties for straw

strength and yield potential with FHB tolerance and grain mycotoxins.

• Marker assisted selection (MAS) to backcross the Sumai3 gene into varieties for irrigated production in Montana.

Backcrossing Scab Resistance

RR X rr

5 generations of breeding

R r

Scab resistance in Choteau

Scab resistant

e.g. MT0550 ‘Sumai3’

Scab susceptible parent e.g. Choteau

Resistant

Susceptible

Heterozygote

Isolate DNA

PCR Copy

Separate on gel

Marker Assisted Selection (MAS)

‘Best management practices’ for FHB in continuous small grains & high production systems

• Resistant variety, certified seed, fungicide seed treatment, half rate fungicide at tillering stage under irrigation

• Center pivot, fill soil profile prior to heading, cut water 10 days before expected flowering date and through flowering period

• Triazole fungicide at or before flowering to prevent infection• Folicur, Prosaro, Proline, Caramba have Sec3 labels

• Manage irrigation thru grain maturation to avoid DON accumulation.

• Post harvest tillage, control volunteer grain, soil incorporation for straw degradation.

Preventing Fusarium head blight

• Use good-quality, high germ seed• Can blow seed out of combine with higher fan speed

at harvest, but this WILL serve as a nice source of inoculum the following year

• Avoid planting a susceptible variety after corn! • Crop rotation to non-host

US Wheat and Barley Scab Initiative