School of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG
phone: +44 (0)117 928 7470
fax: +44 (0)117 331 7985
Speciation in Parasitic Plants
Parasitic flowering plants have fascinated scientists for centuries, yet much of their evolutionary biology remains a mystery. Often, the evolutionary shift to parasitism has been associated with the degeneration of morphological features traditionally used in plant classification, which has made systematic studies of relationships between parasitic plants and their photosynthetic ancestors extremely challenging. Molecular phylogenetic techniques are now giving exciting insights into the evolutionary relationships between parasitic plants and their photosynthetic ancestors, however the speciation processes within most parasitic plant families still receive inadequate systematic attention.
My research focuses on the potential for host specificity to isolate populations of parasitic plants from gene flow, and drive their speciation. Although host-driven speciation processes have been well documented in leaf-eating insects and plant pathogens, the possibility that host-driven speciation also occurs in parasitic plants has remained relatively unexplored. My research uses the experimentally tractable model Orobanche minor (common broomrape) to address the hypothesis that speciation in parasitic plants can be driven by shifts in host preference, using molecular markers, combined with experiments in which host specificity is characterised and quantified. Ultimately my goal is to characterise host-specific, morphologically cryptic species of Orobanche using a molecular phylogenetic approach, which will offer a framework for setting conservation priorities for these taxonomically difficult plants. Studying patterns of genetic divergence among host-specific populations of species such as O. minor will provide a useful model for studying evolution in parasitic plants - one of the most curious and poorly understood groups in the plant kingdom.