Physiological leaf spotting occurs in many forms that may be easily mistaken for spotting symptoms caused by pathogens or herbicides. It is not thought to affect yield. Barley varieties vary in susceptibility to spot formation and the type of spot formed. Initially spots are orange to brown with no rim, but yellowing of tissue between the spots may develop with time. Abiotic factors such as nutrient deficiencies or adverse weather conditions can also cause abnormalities in barley leaves and it is important to distinguish if spots are caused by disease or not before jumping to apply fungicides.
