1 / 11

Fusarium head blight (scab)

Fusarium head blight (scab). Pink mold, whiteheads, tombstone scab Same Fusarium that causes crown rot DON limit 1 ppm. Symptoms. Tan to brown discoloration at the base of the head Diseased spikelets (partial bleaching of the head) or entire head turns white

csilla
Download Presentation

Fusarium head blight (scab)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

  5. Future: Fusarium head blight control X • 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

  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 X • 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

  9. Variety reactions to Fusarium head blight 2006, Grey and Dyer

  10. <2004 YR2007 YR 2005, 2006 Dyer, 2008 Fusarium head scab in Montana Map http://www.peninsulaflyfishers.org/Fishing_Tales/montanaSpring02/montana_map.gif

More Related