Sooty Moulds

Capnodium spp

Sooty Moulds is one of the four main ear diseases to look for. Part of the ear die and turn white or there is a general black discolouration of the ear.

Sooty moulds usually become apparent in late summer, prior to harvest when the entire ear starts to turn a dark colour.

Look out for:

Parts of the ear turning black
General discolouration of the ear

Risk factors:

Warm, humid weather

Infection is via wind borne spores with spores of these diseases being a common component of the air.

This disease is often associated with white heads resulting from stem based diseases.

Sooty moulds tend to be worse when the weather in late summer is warm and humid.

Yield losses from sooty mould infection are rarely great but discolouration of grain can reduce the commercial value of the grain and make it harder to sell.

Related Pests

Glume Blotch

Parastgonospora nodorum

Previously referred to as Septoria nodorum and typically referred to as glume blotch (Parastgonospora nodorum) because it is normally seen on wheat ears, the disease can infect wheat foliage when it is called leaf blotch Leaf blotch can be identified from Zymoseptoria tritici by the lack of black pycnidia and the more oval appearance of the lesions. Glume blotch can be a problem in wet seasons and tends to give the ears a purple-brown appearance.

Leaf Rust - Wheat

Puccinia triticina

Leaf rust (also known as brown rust) is a common disease of wheat which can result in significant yield loss if not controlled. Leaf rust is favoured by warmer, drier conditions with the initial source of inoculum being infected volunteer cereals. Under favourable conditions leaf rust can develop very quickly. Spores are scattered at random on the leaf and are often surrounded by a pale chlorotic halo.

Powdery Mildew - Wheat

Blumeria graminis

Powdery mildew is a common parasitic fungus of wheat. Powdery mildew produces white, fluffy mycelial growth, usually on the leaves but also on the stems and ears and as the disease only infects the outer plant layers it can be scraped off quite easily. Powdery mildew needs to infect living plant material to survive and so wind borne spores from volunteer plants are the likely source of inoculum. Serious disease infections can lead to significant yield losses.

Speckled leaf blotch

Stripe Rust - Wheat

Puccinia striiformis

Stripe rust (Puccinia striiformis) also known as yellow rust, is a common disease of wheat which can result in significant yield loss if not controlled. Stripe rust is favoured by cooler, moist conditions with the initial source of inoculum being infected volunteer cereals. Under favourable conditions stripe rust can develop very quickly forming disease foci surrounding the initial infection source. At first spores tend to be scattered on the leaf but on more mature leaves they show the typical stripe arrangement which gives the fungus its common name. Occasionally stripe rust can infect the ear.