Fig. 7

Phenotypic analysis of OsHKT1;4 RNAi plants in the reproductive growth stage. Nipponbare wild-type and two independent OsHKT1;4 RNAi plants were planted in the same pot filled with paddy-filed soil and grown for approximately 3 months. When the plants started heading, NaCl treatment was initiated by gradually increasing the concentration of Na⁺ in tap water from 25 mM to 100 mM for more than a month. Tissues of the upper parts were excised and washed briefly by the ultrapure water. Ion contents were determined using an inductively coupled plasma optical emission spectrometer (n = 23-28, ±SD). a, Na⁺ content in each tissue. b, K⁺ content in each tissue. FLB: flag leaf blade; FLC: flag leaf sheath; P: peduncle; N I: node I; IN II: internode II; N II: node II. The Welch’s-t test was used for the statistical analysis: * P < 0.01, ** P < 0.001 vs. Nipponbare wild-type