Fig. 4.

pH-dependent rescue of rhd2-1 root hair phenotype. (A–D) Seeds of WT Arabidopsis (A and B) and rhd2-1 (C and D) were germinated for 4 d in continuous light on agar plates containing 1/4-strength Murashige and Skoog (M&S) basal salts, 1% (wt/vol) sucrose and 5 mM Mes, titrated to pH 5 (A and C) or pH 6 (B and D). Roots were imaged by using a Leica Wild M420 stereo microscope. Representative of n > 15 WT and rhd2-1 roots, respectively. (E and F) WT and rescued rhd2-1 root hair at higher magnification. (Scale bar in A, 1 mm for A–D; scale bar in E, 10 μm for E and F. (G) Higher magnification of the bursting phenotype seen in rhd2-1 grown in 1/4-strength M&S medium, pH 5. * indicates burst root hairs. (Scale bar, 100 μm.)