THE GENETICS OF FLOWER DEVELOPMENT - FROM FLORAL INDUCTION TO OVULE MORPHOGENESIS

Flower development consists of several phases. The first step is the t ransition from vegetative to reproductive development, regulated by fl oral induction. Later steps include the initiation of individual flowe rs, the determination of organ identity, and organ-specific differenti ation. One of the major discoveries of plant biology is that the genet ic network controlling flower development is highly conserved in two d istantly related dicots, Arabidopsis thaliana and Antirrhinum majus, a nd probably in other species as well. Classical genetics has identifie d a sizable number of genes regulating flower development, and many of these regulatory genes have been cloned. This review summarizes recen t advances in the understanding of the genetic control of floral induc tion and determination of flower-meristem identity, with the focus on Arabidopsis thaliana. In addition, recent work on ovule morphogenesis, a late process in flower development, is discussed.