Bayer Crop Science Australia logo Crop Science Australia logo
Search
Search
Search

Fusarium head blight

Fusarium graminearum

Fusarium head blight (FHB), also known as head scab, is a serious fungal disease affecting wheat and barley in Australia. FHB can cause significant economic losses, with reports of yield losses ranging from 20 – 100 per cent and major reductions in grain quality. Additionally, the presence of FHB can occasionally produce mycotoxins, which are metabolites produced by the fungi which are toxic to vertebrates in low concentrations. Other hosts include oats, triticale, maize, millet, corn, rye, sorghum and several grasses. 

Fusarium

 

Description

Symptoms are first noticed in the heads of wheat and barley, distinguished by florets that are bleached white or yellow instead of green. Infection that occurs around flowering results in white grains with a chalky appearance which are usually shrivelled and of low weight. Infection closer to maturity causes pink discoloration of the grain. Symptoms are very similar to another disease known as white head disorder. To distinguish between the two requires laboratory testing and if FHB is detected, additional testing for mycotoxins is recommended. 

FHB survives on infected crop residues from one season to the next. Spores (macroconidia) are released from infected residues and either splashed by rain or spread by the wind, infecting susceptible wheat or barley heads. During warm, humid and wet conditions the sexual stage of the fungus (Gibberella zeae) forms as black fruiting bodies on infected plant material. The sexual spores (ascospores) are released into the wind often travelling long distances, infecting plants. FHB is favoured by warm and moist weather during and after flowering. 

Control

FHB outbreaks are highly dependent on weather conditions around flowering time. Preventative practices should be used to help reduce the effects should an outbreak occur. FHB can be seed-borne, therefore any seed suspected to be contaminated should not be used; instead, new seed should be sourced. Durum wheat varieties appear to be more susceptible than bread varieties, so where possible plant varieties with resistance to FHB. Manage stubbles by burying or removal to reduce inoculum levels. Avoid planting into paddocks previously sown with maize, wheat, barley, corn, oats, triticale, millet and sorghum, particularly in years where an outbreak of FHB might be likely. Instead rotate with non-hosting crops such as pulses.
 
If infected grains are retained and used as seed for sowing, blighted seedlings may emerge if left untreated. EverGol® Energy is a broad-spectrum seed dressing which is registered for suppression of seed-borne only FHB (Fusarium spp.) in wheat and barley. Treating seed infected with Fusarium spp. will reduced fungal colonisation of germinating seeds and consequently help reduce seedling blight and levels of crown rot inoculum in paddocks.  EverGol Energy will not protect established plants from new infections (at 130 mL/100 kg). Ensure even coverage of seed for best results. Prosaro® is registered for control of fusarium head blight in wheat and should be applied as a preventative spray at the first sign of flowering.

Related Products

EverGol® Energy Seed Treatment by Bayer Crop Science
Prosaro


References

Grain Growers (Viewed Nov 2019), ‘Head blight’, Fact Sheet, http://www.graingrowers.com.au/wp-content/uploads/2018/04/graingrowers_101805_head-blight_04.pdf

GRDC (2000), ‘Fusarium head blight’, Groundcover Issue 32, https://grdc.com.au/resources-and-publications/groundcover/ground-cover-issue-32/fusarium-head-blight-in-cereals

Department of Primary Industries and Regional Development (2015), ‘Diagnosing fusarium head blight in cereals’, https://www.agric.wa.gov.au/mycrop/diagnosing-fusarium-head-blight-cereals

Schmale, D and Bergstrom, G (2010), ‘Fusarium head blight (FHB) or scab’, https://www.apsnet.org/edcenter/disandpath/fungalasco/pdlessons/Pages/Fusarium.aspx