Project description:To investigate and compare the influence of root exudates of tomato and maize on Pseudomonas donghuensis P482, we have grown the strain up to a stationary phase in M9 0.4% glucose medium supplemented with maize exudates (Maize), tomato exudates (Tomato) or without supplementation (Control). We then performed differential gene expression analysis, identifying changes in transcriptome profiles between each treatment (Tomato, Maize) and the Control as reference conditions, and between the two treatments.
Project description:Soil and rhizosphere bacteria produce an array of secondary metabolites including a wide range of volatile organic compounds (VOCs). These compounds play an important role in the long-distance interactions and communication between (micro)organisms. Furthermore, bacterial VOCs are involved in plant pathogens inhibition and induction of soil fungistasis and suppressivenes. In the present study, we analysed the volatile blend emitted by the rhizospheric isolate Pseudomonas donghuensis P482 and evaluated the volatile effect on the plant pathogenic fungi and bacteria as well as one oomycete. Moreover, we investigated the role of the GacS/GacA system on VOCs production in P. donghuensis P482. The results obtained demonstrated that VOCs emitted by P. donghuensis P482 have strong antifungal and antioomycete, but not antibacterial activity. The production of certain volatiles such as dimethyl sulfide, S-methyl thioacetate, methyl thiocyanate, dimethyl trisulfide, 1-undecan and HCN is depended on the GacS/GacA two-component regulatory system. Apparently, these compounds play an important role in the pathogens suppression as the gacA mutant entirely lost the ability to inhibit via volatiles the growth of tested plant pathogens.
