For a disease to develop in cereal crops, three basic conditions must be met to create what is known as the disease triangle. Firstly, the crop itself must be susceptible to the disease. Secondly, the crop must encounter the pathogen causing the disease, and thirdly the environmental conditions that promote infection and disease development must be right.
If we start with this last condition, the climate in Ireland is mild and damp and is ideal for wet weather diseases that cause most of the issues in Irish crops. Unfortunately, there is very little that farmers can do about our weather, and it should also be noted these are the same conditions that give Irish crops an advantage in terms of yield potential.