The primary objectives of these studies on flower form and function are (1) to establish how floral organs grow and how their growth is modified in the evolution of new forms; and (2) to determine how pollen tubes grow in the style. Specifically, Dr. Lord is continuing the surface growth analyses begun on lily floral organs, extending them to the leaf and to the tobacco flower. She will continue to screen for and select out established floral mutants of Arabidopsis that show modifications in floral form that appear heterochronic in nature, affecting the perianth and androecium form and mimicking the developmental patterns exhibited by both dimorphic flowers of cleistogamous species and those of inbreeding species. Dr. Lord will determine whether differences in protein composition between the dimorphic flowers of Collomia correlates with the histological divergence observed in the anthers and corollas of these two floral types. In the area of pollination, she will continue studies of the interaction between the pollen tube and the stylar medium establishing whether a matrix-driven translocation of pollen tubes occurs in compatible pollinations. %%% The flower is determinate in its growth, producing a serial progression of different parts from embryonic tissue, each showing discrete stages of differentiation, making it an ideal system for studying morphogenesis and growth of plant organs.
