Communication among different species across kingdoms occurs through a chain of regulatory molecules that are transferred around cellular boundaries. These molecules are also crucial for defense, virulence, and pathogenesis. In the past, the transport of proteins in long distance communication was observed, but in the present era, the discovery of extracellular vesicles (EVs) has changed our understanding of molecular communication. EVs are not only involved in cell signaling and immunity but also can transfer information by sRNAs, forming a basis for interactions among a wide variety of organisms. Despite extensive research on EVs in other areas, their role in communication between plants and the plant microbiome has been lacking. EVs are potentially involved in protein trafficking along with the transport of lipids and nucleic acids. Interactions between hosts and their microbiomes may also be mediated by EVs, which can be involved in stress responses, immune surveillance and defense, virulence, and signaling, along with many metabolic activities within plant microbiomes. In this review, we have focused on recent information about the role of EVs and the molecules they transport between hosts and microbes. The connection between biofilms and the generation of EVs is also considered. These findings enhance our knowledge about plant-microbiome interactions in terms of immunity and virulence and challenge the conventional viewpoint of inter-kingdom signaling.
