DescriptionSoil microbiome is essential to maintain plant growth, health and protection against biotic and abiotic stresses. The phenomenon called soil suppressiveness, where plants show significantly reduced disease symptoms even if the pathogen and favourable conditions are present is strongly related to the microbial activity and secondary metabolites production. Among various modes of action of soil bacteria, one of the remarkable but less studied is the production of Volatile Organic Compounds (VOCs). Due to their physicochemical properties, VOCs diffuse easily through gas- and water-filled pores in soil and rhizosphere environments, allowing long-distance interactions. Many bacterial VOCs were found to possess strong antimicrobial activity. We have studied the volatile-mediated antimicrobial activity of tomato rhizosphere isolate Pseudomonas donghuensis P482 against fungal and oomycete plant pathogens (R. solani, V. dhaliae and F. culmorum and P. ultimum). In the VOCs blend produced by Pseudomonas P482, we identified several compounds with sulfur-containing compounds as dominant. We observed clear fungistatic effect caused by the VOCs produced by P482 as well as by the pure compounds S-methyl thioacetate and dimethyl disulfide that were identified in the blend.
However, can we correlate fungistasis with soil suppressiveness? Our recent findings based on screening 28 soils from the Netherlands and Germany indicate that soil suppressiveness and strong soil fungistasis does not always correlate with each other. At present we are exploring the mechanisms involved in both soil fungistasis and suppressiveness.
|Period||05 Jul 2018|
|Degree of Recognition||International|