Sulphur deficiency symptoms in oilseed rape (Brassica napus L.) : The aesthetics of starvation

Deficiency symptoms are the visual response of plants to starvation from essential mineral elements. General characteristics of mineral nutrient deficiencies are the loss of chlorophyll (chlorosis), often followed by the dying off of the plant tissue (necrosis). Only a few nutrient deficiencies produce symptoms in plants, which are unique so that the visual diagnosis can be used for, instance as a tool for fertilizer management. Among all types of mineral nutrient disorders an insufficient sulphur supply of oilseed rape is presumably the only one, which produces characteristic and unmistakable deficiency symptoms at all development stages of the crop. Despite the tragic occurrence of sulphur starvation itself, the symptoms are remarkably outstanding and their detailed description is the objective of this contribution.