CsHAN1 is required for shoot apical meristem development. (A–D) Embryo phenotypes in the normal torpedo stage of the wild type (A), the heart stage in the CsHAN1-RNAi line 49 (B), the retarded torpedo embryo in the CsHAN1-RNAi line 49 (C), and in the CsHAN1-RNAi line 90 (D) at 16 d after fertilization. Bar=50 μm. (E) Phenotypes of wild-type (left), CsHAN1-RNAi line 49 (middle), and CsHAN1-RNAi line 90 (right) seeds at 36h after germination. Bar=1cm. (F) Seed morphology in the WT and CsHAN1-RNAi line 49. Bar=1cm. (G) qRT–PCR analyses of CsWUS, CsSTM, and CsBP in the shoot apexes of the wild type and the CsHAN1-RNAi line. The UBI-ep gene was used as an internal reference to normalize the expression data. (H–M) The expression of CsWUS (H, I), CsSTM (J, K), and CsBP (L, M) in the wild type (H, J, L) and CsHAN1-RNAi line 49 (I, K, M) in the apex of 6-day-old seedlings as detected by in situ hybridization. Bar=50μm. (This figure is available in colour at JXB online.)