Fig. 4. In situ hybridization analysis of wild type, ts4 and ids1;sid1 mutants. Probes are listed at lower left of each panel, genotypes at lower right. (A-E) sid1 in situs. (A) Wild-type maize tassel primordium. (B) sid1-mum2 tassel primordium. (C) Wild-type ear florets with initiating floral organs. (D) ids-mum1 ear florets. (E) ts4-A ear inflorescence. (F-H) kn1 in situs. (F) Cross-section of ear of ids1-Burr. Arrowheads indicate rows. (G) Cross-section of ear of ids1-Burr;sid1-mum3. (H) Close-up of spikelet of double mutant showing prolonged kn1 expression. (I,J) bd1 in situs. Expression marked with arrowheads. (I) Longitudinal section of ids1-Burr;sid1-mum3 ear showing normal expression. (J) Older spikelets of double mutant showing prolonged expression. (K,L) zmm2 in situs. (K) Wild-type ear florets with initiating floral organs. (L) ids1-Burr;sid1-mum3 ear spikelets with ectopic expression in bracts and meristem. (M,N) zag1 in situs. (M) Wild-type ear florets with initiating floral organs. (N) ids1-Burr;sid1-mum3 ear spikelets with ectopic expression in bracts and meristem. Inset shows a younger stage. (O,P) silky1 in situs. (O) Wild-type ear florets with initiating floral organs. (P) ids1-Burr;sid1-mum3 ear spikelets showing no expression. Lo, lodicules.