Seed & Soil-Borne Diseases

Seed & soil-borne diseases

There’s a whole range of seed and soil-borne fungal diseases that can attack and hold back cereal establishment and severely impact yield and quality.

For years, these diseases have been kept at bay because fungicide seed treatments have been routinely used. Neonicotinoid seed treatments (no longer available) were also routinely applied with a fungicide seed treatment. 

Know your risk

Even if planting ‘clean’ tested seed, remember that several of these diseases can also attack from the soil. Did you know that 52% of British soils are estimated to have an incidence of Microdochium nivale?

Below we give information on the key diseases in wheat and barley. 

Seedling blight (Fusarium SP. & microdochium)

Affected crops: Wheat, barley and most cereals.Source of infection: Infected seed, soil and crop debris.Symptoms: Loss of plants, poor establishment, stem based browning, foot rots and ear blights.Impact: Reduced yield and potential mycotoxin issues.

Seed-borne common bunt

Affected crops: Wheat.Sources of infection: Infected seed and soil, wind. Symptoms: In infected ears the grain is replaced by seed-like 'bunt balls' each containing millions of greasy, black, foul smelling (like rotten fish) spores. Impact: Reduced grain quality potentially leading to complete crop rejection.


Affected crops: All cereals.Sources of infection: Predominantly spread by contaminated grain. Secondary spread can occur by wind. Symptoms: The fungus only attacks the ear at flowering, replacing the grain in a few spikelets by a hard, purple-black sclerotium, known as an ergot. Ergots can be up to 2 cm in length. Impact: The disease has little direct effect on yield but the ergots contain large amounts of toxic alkaloids. If used for livestock feed or for human consumption, it can bring health risks and contaminated grain may be rejected. 

Loose smut

Affected crops: Wheat, barley and oats.Sources of infection: Infected seed and wind. Symptoms: In infected ears the grain is replaced by black fungal spores.Impact: Reduced yield and grain quality. 

Leaf Stripe

Affected crops: Barley.Source of infection: Infected seed. The spores produced “in the stripes” are released and infect developing grain on healthy plants.Symptoms: Fungus causes long brown stripes on leaves and can cause ear blindness.Impact: Seed repeatedly sown without treatment multiplies quickly and can result in total crop loss.