Bacterial rhamnolipids are novel MAMPs conferring resistance to Botrytis cinerea in grapevine.

Rhamnolipids produced by the bacteria Pseudomonas aeruginosa are known as very efficient biosurfactant mol- ecules.They are used for a wide range of industrial applica- tions, especially in food, cosmetics and pharmaceutical formulations as well as in bioremediation of pollutants. In this paper, the role of rhamnolipids as novel molecules trig- gering defence responses and protection against the fungus Botrytis cinerea in grapevine is presented. The effect of rhamnolipids was assessed in grapevine using cell suspen- sion cultures and vitro-plantlets. Ca 2+ influx, mitogen-