Biology Sharp eyespot occurs on the lower stems of cereals and some grasses. Wheat is more susceptible than barley, oats and rye.
Winter cereals are more susceptible than spring cereals.
The fungus overwinters on crop residues as a non-spore producing mycelium. The sharp eyespot fungus has a wide host range and infects plants directly through the soil. The eyespot fungus Pseudocercosporella herpotrichioides causes similar damage on winter wheat in Ontario and was reported for the first time on spring wheat in Alberta in 1990. Infections can be severe, particularly on light, dry, acid soils during cool springs. Damage Description Distinct grey to brown spots with dark margins appear at the base of stems at heading.