In-Plate Quantitative Characterization of Arabidopsis thaliana Susceptibility to the Fungal Vascular Pathogen Fusarium oxysporum.

Root vascular pathogens are some of the world's most devastating plant pathogens. However, the methods used to determine plant susceptibility to this class of pathogen are laborious, variable, and in most cases qualitative. Here we present a rapid, simple, and robust infection assay for the characterization of Arabidopsis thaliana resistance to the fungal root pathogen Fusarium oxysporum. The method utilizes fungal root vascular penetrations and fungal-induced root growth inhibition to deliver a quantitative assessment of plant susceptibility with spatial and temporal resolution. These plant susceptibility indicators are paired with a semiautomated data analysis pipeline to deliver a reproducible assessment of plant susceptibility to root vascular pathogens such as F. oxysporum. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Arabidopsis thaliana plate infection assay using fluorescently labeled Fusarium oxysporum Support Protocol 1: Preparation of A. thaliana germination plates Support Protocol 2: Preparation of the F. oxysporum culture Basic Protocol 2: Data acquisition of F. oxysporum plant infection assay Support Protocol 3: Acquiring root growth inhibition data using Fiji.