About this Research Topic
Scientists have attempted to develop microbial formulations that specifically boost plant growth based on direct and indirect capabilities of microorganisms. Direct mechanisms include processes such as nitrogen fixation, production of phytohormones, and the solubilization of nutrients such as phosphate. Indirect mechanisms include the inhibition of phytopathogens by production of secondary metabolites (siderophores, bacteriocins, antibiotics, antimicrobial peptides, and others) or inducing plant systemic responses to protect against pathogens.
The isolation and study of beneficial microorganisms will enable the design of microbial formulations with specific applications in cultivation of field crops. Although certain bacteria are capable of promoting plant growth in the laboratory setting, use of these microorganisms in the field often does not strongly impact crop yields, and the reason for this disconnect may come down to the details of the model organisms being used. For example, the bacterial strain may not be adapted to its new environment (physicochemical characteristics of the soil, plant host, environmental conditions, etc), which affect the microbial and plant genes that are expressed.
Our expanding knowledge of plant microbiomes has begun to reveal some of the microorganisms associated with the rhizosphere or internal tissues of plants. However, this burgeoning knowledge has not yet translated into agricultural applications in the same way as the study of the gut microbiome, where fecal transplantation from healthy to diseased individuals has been shown to restore a functional microbiome. Agriculture poses unique challenges, and the sheer scale of crop production limits the feasibility of using soil transplantation as a means to regenerate unhealthy soil microbiomes. Thus, in order to develop useful microbial formulations, a comprehensive knowledge of microbiomes is needed, including the isolation and characterization of heretofore uncultivable plant-associated microorganisms. The design of new formulations containing such novel microorganisms also requires microbiome knowledge, especially if they are of the second generation, i.e., multispecies formulations containing several compatible microorganisms and tolerant to different stresses.
This special Research Topic has been proposed to receive all kind of submissions, including original research articles, reviews, mini-reviews, new methodologies, analysis of patents, and others, related to plant microbiomes and the design of microbial formulations to increase the growth of plants; the proposed scope includes but is not limited to:
• Isolation and characterization of new microorganisms detected in plant microbiomes.
• Study of microbial mechanisms involved in plant growth, especially when microorganisms implicated are interacting with other microorganisms and the plant.
• Design of mixed microbial formulations based on microbiomes reported to promote the growth of plants under laboratory, greenhouse or field conditions.
• Effects of the application of beneficial microorganisms on the plant microbiome.
• Analysis of patents related to the capacity to promote the growth of plants and its relationship with plant microbiomes.
Keywords: plant microbiomes, PGPR (plant growth promoting rhizobacteria), mixed inoculants, microbial formulations, beneficial microorganisms, microbial consortia, synthetic microbial consortia
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.