Botrysphaeria Head Blight (BHB) - white grain disorder

Botrysphaeria Head Blight - White grain disorder

Description

• Fast growing white fungus on grain
• Kills host tissue and gains nutrient from the dead material
• Stubble borne, favoured by wet periods
• Individual florets or whole heads can be killed
• Shrivelled grains and grains of low weight are also consequences of infection

Damage 

• The direct loss in yield can be severe (>50%).
• Prime hard wheat is downgraded to feed if more than 40 white grains per half litre sample are detected 

Control

There is little knowledge concerning strategies for effective control of BHB. The efficacy of fungicides on the disease is unknown and the little information on varietal response is compromised by differences in maturity, timing of wet periods etc. The value of seed treatments is currently under investigation. As BHB appears to survive on crop trash, stubble management and crop rotation could provide useful levels of control.  Where stubble may be a source of BHB non cereal crops should be sown.

Links and Resources

GRDC - Wheat and barley disease management in 2011. Introduction, possible causes, symptoms, yield loss, recieval standards, and control. Published 2011.