DISSERATION RESEARCH: Evolution of development of the progamic phase in Nymphaeales

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Evolution of development of the progamic phase in Nymphaeales A defining feature of angiosperms is the flower, and flowers are tremendously diverse in the way they look and develop. Much of the diversity of flowers may arise from their role in attracting pollen and/or pollinators. At the same time, flowers must also allow pollen to germinate and form a compatible pollen tube that carries sperm to egg. Although pollination has to occur before a pollen tube can grow, little is known about how evolutionary changes in pollinator attraction correlate with events that happen afterward from pollen tube growth to fertilization. This research uses natural- and hand-pollination experiments to describe fertilization biology in the water lilies (Nymphaeales), a group with diverse flowers and pollination mechanisms. Such data will then be used to correlate evolutionary changes in floral form with post-pollination biology. The specific goal of this award is to gather data from Trithuria (Hydatellaceae), a tiny and poorly understood Australasian plant that is remarkably different from other water lilies. The water lilies represent an independent flowering plant lineage that diverged from the rest of angiosperms over 125 million years ago, and so evolutionary transitions in floral and fertilization biology within this lineage are of great interest to comparative biologists. This project has provided research opportunities for three undergraduates and one local educator, and will provide funding for two additional students to assist with fieldwork in Australia and lab work in the USA. It also facilitates collaboration between University of Tennessee and Western Australian researchers.