1. Fusarium head blight (scab) Pink mold, whiteheads, tombstone scab Same Fusarium that causes crown rot DON limit 1 ppm

2. Symptoms Tan to brown discoloration at the base of the head Diseased spikelets (partial bleaching of the head) or entire head turns white Under moist conditions, pink/orange color is seen (produced by fungal spores and hyphae) on the surface of the glumes Infected kernels are shriveled, white, and chalky in appearance (‘tombstones’)

3. 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)

4. Fusarium head blight history Fusarium graminearum ‘of the grasses’ First described in early 1900s Occurrence of Fusarium head blight in the USA 1991-1996

5. Future: Fusarium head blight control Rotation Fungicide application at flowering –Folicure, what others? Quilt? –May not be economical Use a ‘more resistant’ variety –Many resistant varieties from other regions of the country are not adapted to MT conditions X

6. Fusarium head blight pathogen Residue-borne –Corn & wheat residue ‘massively colonized’ –Scabby seed blown out of the combine in the previous year Conidiospores (asexual) splash dispersed, Ascospores (sexual) forcibly ejected from asci Infection occurs when spores land on susceptible heads Most susceptible at flowering Limited by moisture

7. 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)

8. Future: Fusarium head blight control Rotation Stop irrigation before first flowering: 10-14 days Fungicide application at flowering –Folicur (Sec. 18 next year?, Proline or Prosaro label 2008?) –May not be economical Folicur $6/A; Proline $17.50/A –Need to combine tolerant varieties with fungicide application –Orient nozzles towards heads, not downwards (forward/backward, not just forward) Use a ‘more tolerant’ variety –Many varieties from other regions of the country are not adapted to MT conditions –No/poor resistance currently available in malt barley X

9. VarietyLodgingErgotScabYield (Bu/a) ACS526107%++2% 87 Glenn31%+2% 67 MT055048%+3% 79 Alsen10%+4% 68 Granite1%++++5% 75 Freyr77%+6% 85 Knudson63%+6% 81 9820127-06 16%-8% 91 MT055136%+++10% 67 Howard63%-12% 69 Kelby23%+18% 79 Espresso0%-21% 76 Vida50%-23% 68 Hank (CK)0%-47% 53 2006, Grey and Dyer Variety reactions to Fusarium head blight

11. Fusarium head scab in Montana Map http://www.peninsulaflyfishers.org/Fishing_Tales/montanaSpring02/montana_map.gif <2004 YR 2005, 2006 YR2007 Dyer, 2008