Abstract
BackgroundThe Arabidopsis thaliana-Pseudomonas syringae model pathosystem is one of the most widely used systems to understand the mechanisms of microbial pathogenesis and plant innate immunity. Several inoculation methods have been used to study plant-pathogen interactions in this model system. However, none of the methods reported to date are similar to those occurring in nature and amicable to large-scale mutant screens.ResultsIn this study, we developed a rapid and reliable seedling flood-inoculation method based on young Arabidopsis seedlings grown on MS medium. This method has several advantages over conventional soil-grown plant inoculation assays, including a shorter growth and incubation period, ease of inoculation and handling, uniform infection and disease development, requires less growth chamber space and is suitable for high-throughput screens. In this study we demonstrated the efficacy of the Arabidopsis seedling assay to study 1) the virulence factors of P. syringae pv. tomato DC3000, including type III protein secretion system (TTSS) and phytotoxin coronatine (COR); 2) the effector-triggered immunity; and 3) Arabidopsis mutants affected in salicylic acid (SA)- and pathogen-associated molecular pattern (PAMPs)-mediated pathways. Furthermore, we applied this technique to study nonhost resistance (NHR) responses in Arabidopsis using nonhost pathogens, such as P. syringae pv. tabaci, pv. glycinea and pv. tomato T1, and confirmed the functional role of FLAGELLIN-SENSING 2 (FLS2) in NHR.ConclusionsThe Arabidopsis seedling flood-inoculation assay provides a rapid, efficient and economical method for studying Arabidopsis-Pseudomonas interactions with minimal growth chamber space and time. This assay could also provide an excellent system for investigating the virulence mechanisms of P. syringae. Using this method, we demonstrated that FLS2 plays a critical role in conferring NHR against nonhost pathovars of P. syringae, but not to Xanthomonas campestris pv. vesicatoria. This method is potentially ideal for high-throughput screening of both Arabidopsis and pathogen mutants.
Highlights
The Arabidopsis thaliana-Pseudomonas syringae model pathosystem is one of the most widely used systems to understand the mechanisms of microbial pathogenesis and plant innate immunity
To establish an improved highthroughput assay to study the plant-bacterial interactions, in this study, we developed an improved, rapid and reliable seedling flood-inoculation method using Arabidopsis, a model plant that produces six to eight rosette leaves within two-weeks, in standard Petri plates containing Phytagel supplemented with Murashige and Skoog (MS) salts
We further demonstrated that this method is suitable for the investigation of bacterial virulence mechanisms, plant nonhost resistance (NHR) and plant signaling pathways related to PTI and effector-triggered immunity (ETI)
Summary
The Arabidopsis thaliana-Pseudomonas syringae model pathosystem is one of the most widely used systems to understand the mechanisms of microbial pathogenesis and plant innate immunity. One of the model pathosystems for the study of plantpathogen interactions is Arabidopsis thaliana-Pseudomonas syringae interaction [1]. This model system has been widely used to understand a number of dynamic and complex molecular events in both resistance and susceptible interactions. Tomato strain DC3000 (Pst DC3000), which causes bacterial speck disease of tomato, has been used as a model pathogen for investigating the molecular basis of plant-pathogen interactions because of its pathogenicity on Arabidopsis [1,2]. The virulence function of a large number of potential virulence effectors encoded by the Pst DC3000 genome and their mode of action is still unknown
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
