Life cycle and reproductive botany of Scilla hyacinthoides, a Mediterranean geophyte.

The Mediterranean region is abundant with geophyte species, many of which have been developed as ornamentals. In recent years attempts were made to grow Scilla hyacinthoides L. (Asparagaceae, subfamily Scilloideae) commercially, both as a cut flower and as a water-saving ornamental geophyte. Optimizing commercial production of S. hyacinthoides requires the study of growth and development of the vegetative plant, as well as the control of flower bud initiation and development. Like most Mediterranean plants, S. hyacinthoides life cycle is attuned to the annual rhythm which alternates between hot and dry summer, and cool and rainy winter. Plants are dormant during summer. In autumn the apical meristem becomes active and either begins producing leaves for the next season, or initiates inflorescence development. After the onset of inflorescence development, a new apical meristem is formed at the axil of the youngest leaf. Frequently, two apices are formed; one of them becomes a daughter bulb. Intrabulb development of the inflorescence was studied by histology and electron microscopy. The flowering occurs in spring. Floral initiation is temperature-dependent and is inhibited by low temperatures, but inflorescence differentiation and elongation is inhibited by high temperatures. Flowers are self-incompatible and exhibit several polymorphic traits, probably important in pollinator attraction. In summary, current research provides a basis for future studies on the florogenesis and ecophysiology in Scilla , as well as enabling future fine tuning of cultivation protocols for the flower industry. [ABSTRACT FROM AUTHOR]