Fig. 1.

Strategy for enriching and bioassaying MtCEP1 peptides using root cultures. (A–D) Axenic root cultures containing either the vector (A, C) or MtCEP1ox (B, D). Root cultures were maintained on solidified Fåhraeus medium (A, B) prior to sub-culturing in liquid Fåhraeus medium (C, D) for peptide isolation. (A) and (B) show one week’s growth after adding an equally-sized root segment to the agar plates and (C) and (D) show two week’s growth in the liquid medium after equally sized root segments were initially sub-cultured. (E) The concentrated exudates from vector control and MtCEP1ox root cultures were incorporated into Fåhraeus medium to a final concentration of 1% of that present in the harvested flasks and bioassayed for inhibition of emerged lateral root number on wild type A17 seedlings (measured as LR number/cm) n=12.