One of the important aims in a control of plant disease is to reduce the use of pesticides by supplying compounds able to stimulate the defence mechanism of host plant against pathogens.
Plants recognize certain compounds as elicitors of their active defence mechanism.
The elicitors-treated tissues may become protected against subsequent inoculation by pathogen. On the other hand, fungi synthetize many low molecular compounds, toxins, able to influence considerably the metabolism of plant cells and kill them. The molecular mechanism of the interaction of elicitins and toxins is a subject of many studies. Molecular mechanism of the activity of extracellular proteins from pathogenic fungi Phytophthora . These elicitors cause hypersensitive-like reaction in tobacco plants.