Extended Data Fig. 5: Loss of Hvmads1 leads to reduced meristem determinacy and delayed inflorescence development under high temperature.
From: MADS1 maintains barley spike morphology at high ambient temperatures
a,b, Scanning electron microscopy of spike morphology at W2.5, W3.5 and W7 in WT (GP) (a) and hvm1 (b) plants at 15 °C, showing the short awn in hvm1. c, Morphology of the developing WT spike at 28 °C. d, Reduced meristem determinacy of hvm1 inflorescences at 28 °C. Green asterisks indicate the indeterminate inflorescence meristem likely converted from the central spikelet meristems, yellow asterisks indicate the ectopic initiated meristems or inflorescence/spikelet meristems possibly reverted from rachilla. e, Effects of ambient high temperatures 20 °C, 23 °C and 25 °C on morphology of hvm1 spike. Yellow shading indicates EI, blue shading indicates ES. All bars (a–e) = 100 µm. fm, floral meristem; ls, lateral spikelet; cs, central spikelet; gl, glume; st, stamen; pi, pistil; le, lemma; esm, ectopic spikelet meristem; eim, ectopic inflorescence meristem. f, Rate of spike development at different temperatures, showing delay in hvm1 (GP) at 28 °C, compared with WT, spike development. Bars = 0.5 mm. g, Days to reach different Waddington stages of spike development at 15 °C and 28 °C in three barley varieties and related hvm1 mutants. Data shown as mean ± s.d. P < 0.001, two-way ANOVA tests of WT and hvm1 (three background comparisons) at 28 °C. All experiments with treatment were repeated independently at least three times with similar results.
