The use of herbicides to control weeds is very common. However, some herbicides are both environmentally detrimental and human unhealthy. The use of microorganisms acting as natural herbicide could be an alternative control method. Symptomatic weeds will be collected in field. Microorganisms will be isolated from symptomatic weeds, purified, identified and inoculated on weeds to confirm Koch’s postulates. The identified pathogenic microorganisms will be tested against a selection of weeds and crops to characterize the host range and the specificity of these microorganisms. In parallel, the diversity of endophytic microorganisms of symptomatic weeds will be characterized by high-throughput sequencing of microbial barcodes. This approach will allow to identify microorganisms unable to grow rapidly on media. Eventually, the modes of action leading to death of weeds will be sought to identify those responsible and value as metabolites bioherbicides.