Role of the microbiome on the maturation of plant innate immunity
B. PAASCH (1), J. Kremer (1), B. Kvitko (2), J. Jerome (1), J. Tiedje (3), S. He (4) (1) Michigan State University DOE Plant Research Laboratory, U.S.A.; (2) University of Georgia Department of Plant Pathology, U.S.A.; (3) Michigan State University Center for Microbial Ecology, U.S.A.; (4) Howard Hughes Medical Institute, Michigan State University DOE Plant Research Laboratory, U.S.A.

To protect against the infection of pathogenic microbes, plants possess an immune system capable of recognizing conserved microbe-associated molecular patterns (MAMPs) and pathogen virulence effectors and, subsequently, eliciting defense responses. Whether the plant innate immune system needs a maturation process post-germination in order to function properly is not known. Nonetheless, plants are inherently associated with a multitude of microbes, collectively known as the plant microbiome.  While both the plant microbiome and plant immunity have been studied individually, how endogenous microbiota may influence the plant innate immune system is not well understood. The presented work aims to investigate this knowledge gap. Comparing the transcriptomes of Arabidopsis grown in the presence or absence of soil microbiota revealed impaired expression of transcripts associated with plant-defense in plants lacking a microbiome. Microbe-free plants are also more susceptible to the foliar pathogen Pseudomonas syringae pv. tomato DC3000. Furthermore, in plants lacking a microbiome, specific components involved in MAMP-triggered immune signaling exhibit a diminished ability to be activated as well as significantly altered intracellular concentrations of defense-related phytohormones. Taken together, our data suggest that the plant immune system requires a microbiome-mediated maturation process post-germination to function properly.

Abstract Number: P4-112
Session Type: Poster