Abstract Detail

Botany 2021 and ASPB Special Symposium

Pieterse, Corné [1], Stringlis, Giannis [1], Yu, Ke [1], Vismans, Gilles M. [1], Song, Yang [1], de Jonge, Ronnie M. [1], Bakker, Peter M. [1], Berendsen, Roeland [1].

Bidirectional communication along the microbiome-root-shoot axis.

Plants nurture a large community of root-associated microbiota, which provide them with essential services, such as enhanced nutrient uptake, growth promotion, and protection against pathogens. Our research is focused on understanding plant-beneficial functions encoded by the root microbiome and the role of plant genes facilitating these functions. Recently, we demonstrated that upon foliar pathogen infection, plant roots recruit a consortium of synergistic microbes to their rhizosphere that in turn trigger an immune response in the whole plant body. Using the Arabidopsis-Pseudomonas simiae WCS417 model, we identified the root-specific transcription factor MYB72 as a central regulator in the onset of this induced systemic resistance (ISR), which is typically effective against a broad spectrum of plant pathogens. Metabolomics revealed that MYB72 controls the biosynthesis of the iron-mobilizing coumarin scopoletin, which is excreted in the rhizosphere where it aids in iron uptake. Scopoletin also has antimicrobial activity to which beneficial WCS417 is insensitive. Microbiome analysis of coumarin-deficient Arabidopsis mutants revealed that scopoletin functions in rhizosphere community assembly, possibly to promote recruitment of immunity-stimulating rhizobacteria to the roots. A major question in plant-microbiome interactions research is: how do plant roots distinguish beneficial from harmful microbes? Recently, we showed that over 40% of the root-associated microbiota are capable of suppressing local root immune responses, therewith facilitating root colonization⁸. The rhizosphere is a MAMP-rich environment. Hence, we believe that suppression of root immunity is an important function of the root microbiome as it prevents growth-defense tradeoffs that are typically associated with the activation of MAMP-triggered immunity. Understanding the mechanistic basis of mutually beneficial plant-microbiome interactions provides a firm knowledge basis for the development of future crops that maximize profitable functions from the root microbiome.

1 - Utrecht University, Institute of Environmental Biology, Utrecht, The Netherlands

Keywords:
none specified

Presentation Type: Special Sessions
Session: SY4, Botany 2021 and ASPB Special Symposium
Location: Virtual/Virtual
Date: Wednesday, July 21st, 2021
Time: 11:00 AM(EDT)
Number: SY4001
Abstract ID:1165
Candidate for Awards:None