Branching phenotypes and GR24 (SL analog) rescue of the zmccd8::Ds mutant. A, Axial bud length of zmccd8 seedlings at 14 d after germination. Mutant buds are significantly longer (P < 0.05, ANOVA). Values are means ± se (n = 7 for zmccd8; n = 4 for the wild type). B, Outgrowth of the two, lowermost axial buds (arrows) in zmccd8 seedlings at 21 d after germination. C, Suppression of bud outgrowth in zmccd8 seedlings by GR24. Seedlings were grown hydroponically and supplied with 1 μm GR24 or DMSO (control). Bud length was measured at 21 d after planting (corresponding to emergence of the 5th leaf). Mutant buds treated by GR24 are significantly shorter (P < 0.05, ANOVA). Values are means ± se (n = 4). D, Outgrowth of the axial buds in third and fourth position from the base (red arrows) of 6-week-old zmccd8 plants grown in the field. E, Time course of visible outgrowth by axial branches appearing above subtending leaf sheaths of zmccd8 mutant (diamonds) or wild-type plants (squares). The zmccd8 mutants had statistically more axillary branches (P < 0.001, ANOVA) at 42 d after planting. Values are means ± se (n = 25 for zmccd8; n = 14 for the wild type). F, Morphology of a mature zmccd8 mutant (left) compared to a wild-type plant (right) at 3 weeks after pollination. Ruler = 30 cm. WT, wild type.