Pollen Ontogeny in the Giant Water Lily Victoria (Nymphaeaceae)
Patrick J. Hudson* and Jolene M. Miesner
Dr. Jeffrey M. Osborn, Faculty Mentor
An endemic of South America, the water lily genus Victoria contains two species, Victoria amazonica and Victoria cruziana, as well as several hybrids. Victoria is a member of the family Nymphaeaceae, which is considered to be one of the most primitive lineages of flowering plants. Although studies of pollen development generate important clues to evolutionary relationships, little is known about these characters in Victoria. This study has used light and electron microscopy to investigate pollen development in V. amazonica, V. cruziana, and the ‘Longwood’ hybrid. The objective of this research was to comparatively document ontogenetic changes in the pollen during the major stages of development, including the sporogenous, microspore mother cell, tetrad, free microspore, and mature stages. At each stage, several key features were analyzed, including size, tetrad configuration, and wall ultrastructure. While mature pollen grains of V. amazonica and V. cruziana are fused into permanent tetrads, variations in tetrad configuration and polyads have been observed in ‘Longwood’ hybrid.
Keywords: Victoria, water lilies, pollen development, Nymphaeaceae, Nymphaeales, giant water lily, aquatic plants, phylogeny
Presentation Type: Oral Paper
Location: VH 1010