Fig. 6.

²⁴Na⁺ efflux from roots of intact, 21-day-old seedlings of IR29 (A) and Pokkali (B), grown and measured at 35 mM and 50 mM [Na⁺]_ext, respectively (cultivar Na⁺ EC₅₀ values), with or without Si (1.67 mM). Respiratory inhibitors KCN and SHAM (when used) were applied at t=22.5 min (from the beginning of the elution protocol; see arrows) onwards. Data are represented as the mean (SEM<15% of the mean; n=3–7). Efflux and influx values calculated from these data are shown in Supplementary Fig. S4. Measurements taken at 30 °C in seedlings grown under a 30/20 °C (day/night) temperature cycle.