Research Topics
Our research aims to understand the role of environmental factors on plant competition and productivity.
Parasitic plants are a major cause of food insecurity globally, particularly in developing countries. However, the mechanisms by which different types of parasites cause damage are poorly understood, hindering the development of effect mitigation strategies.
Parasitic plants can be split into different classes based upon their point of attachment (root / shoot), their nutritional mode (photosynthetic hemiparasites / non-photosynthetic holoparasites) and their ability to grow independantly (facultative / obligate).
In our lab we explore the role of biotic and abiotic factors on the host - parasite relationship, using the facultative hemiparasite Phtheirospermum japonicum and the holoparasite Orobanche minor.
We use a variety of ecophysiological techniques to elucidate the relationships between hosts and parasites, often using root boxes which allow us to precisly control resource supply to each plant separately. Isotopic tracers (13CO2 / 15N) are often used to quantify fluxes between plants. Standard methods to measure plant performance (growth rates, photosynthetic rates, elemental analysis, etc) allow a greater understanding of the physiological effects of parasitism. The photograph to the left shows an alfalfa plant being 13CO2 and 15N double labeled to investigate the flux of resources from the host to the P. japonicum parasite.
A second research theme involves understanding plants response to heterogeneous nutrient supplies, and how this influences plant - plant competition. It is well-known that many species of plants exhibit nutrient-foraging behaviours under low-resource conditions. For example, some species grow more roots in nutrient-rich patches. Our work seeks to explore the physiological basis for differential root growth, and understand the importance of these behaviours in plant ecological interactions. The photo shows an experiment designed to explore the influence of aboveground competition for light on belowground competition for nutrients.
