[en] rhizobacteria ; induced systemic resistance ; biological control
[en] Abstract: A better understanding of biotic and environmental factors that regulate the production of active metabolites by beneficial rhizobacteria is crucial for optimising biocontrol under pratical conditions. In this study, we wanted to evaluate the effect of some parameters on the production of the plant defence elicitor synthesized by Pseudomonas putida BTP1. This molecule is clearly dependant of the secondary metabolism and chemostat experiments showed that the elicitor is more efficiently produced at a very low cell growth rate. On another hand, the presence of free amino acids in the medium is necessary to obtain an optimal NABD production. A specific positive effect of phenylalanine was evidenced in pulsed continuous cultures suggesting that this residue could play a role as a precursor and/or act as a regulator in the biosynthetic pathway.