However plant nutrients can also help the plant protect itself from disease. A well balanced nutrition programme will ensure that the plants cellular structure is robust and resilient, whilst avoiding excessive nutrient build up that can also be detrimental to plant health. There are numerous examples of nutrients being cited for their role in plant health, with nitrogen, potassium, manganese, zinc, copper and molybdenum being examples.
Nitrogen applications can have the effect of encouraging foliar diseases, particularly applications later in the season which delay maturity and increase the risk of blight infection.
Calcium is an important nutrient for preventing tuber diseases since by strengthening cell walls it also strengthens tuber skins so providing better resistance to many diseases. Boron enhances the effect of Calcium by improving uptake and so and can reduce levels of common scab and other tuber diseases, Zinc can minimise powdery scab Sulfur may reduce both powdery and common scab infection.