Halo Spot
Halo spot on winter barley & Halo spot on spring barley
Halo spot on winter barley & Halo spot on spring barley
Fungus
Barley, grasses particularly timothy and cock's foot
Lesions are small, often square or rectangular with refined dark brown margins. Small black spore cases occur in lines in the centre of the lesion. Lesions are much smaller than Rhynchosporium and differentiation can easily be made. They occur on the leaf, stem and ear.
Inoculum for the disease come from the stubble, volunteers or infected seed. Spread is mainly from watersplash.
Wet weather. Most common in South West England.
Can cause economic loss in severe cases but in most parts of the UK halo spot is not considered to cause significant yield loss.
Some fungicides have been shown to give some degree of reduction or control of this disease.
Find out more information on the key disease threats to your cereal crop. For each disease you will find out the importance of the disease in terms of potential yield penalty, how to identify the disease in its early stages and our advice on the best control strategies.