Good sulphur nutrition leads to an increase in compounds known to improve human health. These include phenolic compounds and glucosinolates. Phenolic compounds - namely caffeic acid derivates and flavonols - have been linked to the reduction of chronic diseases and reduced risks of cancer. Glucosinolates, as well as adding to taste and improving a plant’s ability to resist stress, are also anticarcinogens.
Manganese is required for chlorophyll formation and oxide-reduction reactions in cells, and increases vitamin C contents. It is also involved in the metabolism and synthesis of proteins. Crops that are well supplied with manganese have higher vitamin C contents.
Several studies have also shown that potassium supply increases vitamin C levels in the crop.
Brassica vegetables contain useful levels of calcium which has proven health benefits in the human diet. This nutrient ensures vigorous leaf, root and canopy growth and has important roles for crop quality too. Although the total calcium uptake of brassica crops is high, the quantity of it which is finally removed from the field at harvest is usually relatively low. To maintain levels a good supply of calcium from the soil is needed.