Fig. 5: Lacking ZmESBL function leads to a defective endodermal CS barrier.

a, b PI penetration-based assay of the function of endodermal CS barrier in the primary roots of the plants grown under control (a) and salt (b) conditions (genotypes as indicated). PI penetration assay was performed at 1.5 cm, 2.0 cm, 2.5 cm, 3.0 cm, and 3.5 cm from the root apex (see methods). The wild-type roots under control condition were analyzed via both longitudinal and cross sections. en, endodermis; x, xylem. c A graphical demonstration of the function of the endodermal CS barrier between ZmESBL^crispr and wild-type plants. The red dash lines indicated Casparian strip, and the solid red lines indicated the fully functional CS barrier. d Demonstration of the separation of root stele from the outer part tissues. e The Na⁺ contents in stele and outer part tissues of the indicated root segments. The roots of 3 days old seedling were treated with 200 mM Na⁺ for 15 mins, and then the indicated root segments were collected and sampled as demonstrated in (d). The Na⁺ contents were expressed as mg/g fresh mass (FM). DRA, distance to root apex. f–h Na⁺ concentrations in the root (f), xylem sap (g) and shoot (h) of plants grown under indicated conditions. The images in (a) and (b) were representative of three independent repeats with similar results. The results in (e–h) were means ± s.d. of three independent experiments. Bars in (a) and (b), 40 μm. Statistical significance was determined by a two-sided t-test. Source data are provided as a Source Data file.