Redi earth soil

For most experiments, Arabidopsis thaliana plants were grown in “Arabidopsis Mix” greenhouse potting soil (equal parts of SUREMIX [Michigan Grower Products Inc.], medium vermiculate and perlite; autoclaved once) or Redi-Earth soil (Sun Gro Horticulture) in air-circulating growth chambers for colonization of phyllosphere microbiota. Plants were grown under relative humidity set at 60%, temperature at 22°C, light intensity at 100 μE⋅m²⋅s and photoperiod at a 12 h light-12 h dark cycle. Five-week-old plants were used for bacterial inoculation and microbiota assays.
The wild-type accession Col-0, min7 fls2 erf cerk1 (mfec), ben3 (i.e., cad1–5 used in this study) and dde2–2/ein2–1/pad4–1/sid2–2 (deps) mutant derivatives were described previously^{1 (link),21 (link),32 (link)} or in this study. The big2–1 (SALK_033446) and big2–2 (SALK_016558) T-DNA insertion mutants were obtained from the Arabidopsis Biological Resource Centre (ABRC) at The Ohio State University.

Arabidopsis thaliana plants were grown in the “Arabidopsis Mix” soil (equal parts of SUREMIX [Michigan Grower Products Inc., Galesburg, MI], medium vermiculate and perlite; autoclaved once) or Redi-Earth soil (Sun Gro^® Horticulture) in environmentally-controlled growth chambers, with relative humidity at 60%, temperature at 22 °C and 12h light/12h dark cycle. Five-week-old plants were used for bacterial inoculation and disease assays.
The bak1-5/bkk1-1/cerk1mutant plant was generated by crossing the bak1-5/bkk1-1 mutant^{14 (link)} with the cerk1 mutant^{29 (link)}. PCR-based genotyping was performed in F₂ progeny to obtain a homozygous triple mutant. The npr1-6 (Fig. 4a) mutant was the SAIL_708_F09 line ordered from the Arabidopsis Biological Resource Center, and confirmed to be a knock-out mutant and defective in SA signaling (Extended Data Fig. 6).