Expression Analysis of B-class MADS-box Genes from Catalpa speciosa Cloning and Expression Analysis of B Class MADS-box Gene AcDEF Associated with Floral Development in Onion Cloning DNA Fragment of APETALA1 Homologue of the Citrus MADS-box Cloning DNA Fragment of APETALA1 Homologue of the Citrus MADS-box Duplication and Divergence of Floral MADS-Box Genes in Grasses: Evidence for the Generation and Modification of Novel Regulators Evolution and function of MADS-box genes involved in orchid floral development Identification and expression of floral organ homeotic genes from Alpinia oblongifolia (Zingiberaceae) Cloning and Expression Analysis of B Class MADS-box Gene AcDEF Associated with Floral Development in Onion Interactions among proteins of floral MADS-box genes in Nuphar pumila (Nymphaeaceae) and the most recent common ancestor of extant angiosperms help understand the underlying mechanisms of the origin of the flower