Shoot and floral meristem activity in higher plants is controlled by complex signaling networks consisting of positive and negative regulators. The Arabidopsis ULTRAPETALA1 (ULT1) gene has been shown to act as a negative regulator of meristem cell accumulation in inflorescence and floral meristems, as loss-of-function ult1 mutations cause inflorescence meristem enlargement, the production of ex...

MADS box genes play important roles in specifying floral meristem and floral organ identity. We characterized the temporal and spatial expression patterns of two members of this gene family, AGL4 and AGL5 (for AGAMOUS [AG]-like). AGL4 RNA initially accumulates after the onset of expression of the floral meristem identity genes but before the onset of expression of the floral organ identity gene...

Traditionally, plant-pollinator interactions have been interpreted as pollination syndrome. However, the validity of pollination syndrome has been widely doubted in modern studies of pollination ecology. The pollination ecology of five Asian Buddleja species, B. asiatica, B. crispa, B. forrestii, B. macrostachya and B. myriantha, in the Sino-Himalayan region in Asia, flowering in different loca...

Gibberellins (GAs) are a class of plant hormones involved in the regulation of flower development in Arabidopsis. The GA-deficient ga1-3 mutant shows retarded growth of all floral organs, especially abortive stamen development that results in complete male sterility. Until now, it has not been clear how GA regulates the late-stage development of floral organs after the establishment of their id...

Title of Document: POLLINATOR SPECIALIZATION AND THE EVOLUTION OF POLLINATION SYNDROMES IN THE RELATED SILENE, S. CAROLINIANA, S. VIRGINICA, AND S. STELLATA Richard James Reynolds, Ph.D., 2008 Directed By: Associate Professor, Charles B. Fenster, Biology Associate Professor, Michele R. Dudash, Biology Pollination syndromes are the convergent expression of floral traits in unrelated species refl...

I. National Territories and Global Processes................... 571 II. National Borders and Subnational Scalings of the Global........................................................................ 580 III. National Borders and Subnational Borderings ........... 586 A. Positioning a Site in a Global Web of Borders .................. 589 B. Disembedding the Border from Its National Encasements...

BACKGROUND AND AIMS Pollinator landscapes, as determined by pollinator morphology/behaviour, can vary inter- or intraspecifically, imposing divergent selective pressures and leading to geographically divergent floral ecotypes. Assemblages of plants pollinated by the same pollinator (pollinator guilds) should exhibit convergence of floral traits because they are exposed to similar selective pres...

We addressed the potential effects of changes in ambient temperature on the profiles of volatile emissions from flowers and tested whether warming could induce significant quantitative and qualitative changes in floral emissions, which would potentially interfere with plant-pollinator chemical communication. We measured the temperature responses of floral emissions of various common species of ...