Floral morphogenesis in Sinofranchetia (Lardizabalaceae) and its systematic significance

The floral organs of Sinofranchetia chinensis Hemsl. (Lardizabalaceae) are all spiral in initiation. Stamen and petal (nectar-leaf) primordia initiate independently and are different in shape. The petals and three stamens in the first whorl are retarded in the early developmental stages. The carpel primordia are conduplicate; the stigma is formed around the upper part of the ventral slit and the style is not differentiated. The functionally unisexual flowers are bisexual in organization in the early developmental stages. The development of the flowers on the inflorescence is spiral and centripetal. Some floral characteristics of Sinofranchetia appear to be plesiomorphic in Lardizabalaceae. (C) 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160, 82-92.