Cereal disease management will requires a greater focus due to recent seasonal conditions and increased stubble loads that will increase the prevalence of diseases.

The following diseases and pests are of concern:

Yellow Leaf Spot

• Situation: Wheat on Wheat
• The disease survives on wheat stubble over summer
• Spores are released during the following growing season when humid conditions prevail
• Infection occurs on wheat plants when spores are present and the leaves are wet for more than six hours.  Infection can occur at any stage of crop development, and can spread over the whole plant
• The disease is identified by tan-brown spots, surrounded by a yellow margin.  When the spots join the leaf dries out and withers
• Significant yield loss can occur from severe infection

Strategies  to minimise Yellow Leaf Spot:

–      avoiding sowing wheat back into wheat stubbles
–      selecting a variety with some resistance such as Strzelecki, Sunvex, Ellison or Lincoln
–      infected stubble removal through burning
–      foliar fungicides such as Propiconazole (Tilt) can assist to manage disease in the crop, however application timing can be difficult

Take-all

• Situation: Wheat on Wheat
• The disease infects the root systems of winter cereals
• Take-all survives over summer on cereal stubbles and alternate grass hosts such as barley grass, brome grass and silver grass
• Disease levels are often higher following warm, wet springs that favour inoculum buildup
• Symptoms include blackened root systems, premature haying-off and distinct patches of whiteheads

Strategies to minimise Take-all:

–      rotating to non host crops such as canola
–      ensuring that alternative hosts such as volunteer cereals and grass weeds are controlled
–      seed dressings such as Jockey ($15/ha) or Impact fertilizer treatment ($5/ha) can be used to suppress the disease in situations where it is anticipated to be a problem. The benefit can be even more significant if Stripe Rust control is also required

Crown Rot

• Situation: Wheat on Wheat
• The disease affects wheat and barley crops by damaging the crown and lower stems, reducing the uptake of water and nutrients 
• Crown Rot survives over summer on cereal stubbles and will be present in paddocks as long as the residues remain
• Moist conditions early in the growing season favour infection
• Symptoms and yield loss are highest in dry springs

Strategies to minimise Crown Rot:

–      rotation to non-host crops such as canola
–      ensuring all cereal residues break down
–      sowing between previous rows will afford a level of physical separation from the disease
–      removal of infected stubble through burning

Other diseases of note:

Leaf Scald

• Situation: Barley on Barley
• The disease survives on barley stubbles over summer
• Spores are released during the following growing season and are dispersed by rain splash

Strategies  to minimise Scald:

–      avoiding sowing barley back into barley stubbles
–      choosing a variety with some resistance such as Hindmarsh
–      seed or fertilizer treatments can provide early control and manage inoculum buildup

Net Blotch

• Situation: Barley on Barley
• The disease has two forms, Spot Form and Net Form
• Both forms survive over summer on barley stubble and produce dark brown lesions
• Net Form Net Blotch can infect seed
• Spore production is favoured by moist conditions and temperatures above 15°C

Strategies  to minimise Net Blotch:

–      avoiding sowing barley back into barley stubbles
–      choosing a variety with some resistance such as Hindmarsh
–      foliar fungicides such as Propiconazole (Tilt) offer some protection, however application timing can be difficult

Pests of note:

Slugs

• Situation: emerging crops and pastures adjacent to creeks, roadways, rocky outcrops and pasture paddocks
• Bare areas affected by slugs can increase significantly in size within days

Strategies to minimise crop damage:

–      removing stubble residues through burning
–      removal of habitat where possible
–      baiting with pellets containing Metaldehyde

Mice

• Populations supported by high stubble loads and spilt grain

Strategies to minimise crop damage:

–      early burning to remove habitat and food source
–      cultivation to destroy habitat