University of Tasmania, Australia

Drying out is the most universal threat to the survival of land plants, and since the first invasion of the land over 450million years ago plants have produced an array of adaptations to conserve water and preserve their tissues during water shortage. This project examines the backbone of land plant evolution and reconstructs how the most fundamental adaptive drought-avoidance functions have evolved. We focus on evolution in two main areas; the function of stomata and the vascular system of water transport in plants. The control of the stomatal valves in leaves determine how effectively plants can guard against excessive water loss, and the competence of the water transport system defines the point during water stress at which plants begin to catastrophically desiccate. Our discoveries to date have changed the understanding of how plants interact with their environment and we are building a new picture of not only the functional evolution of land plants, but also details about specific mechanisms involved in plant death or survival during water shortage.

This project is motivated by the need to understand how plants have adapted to water stress throughout history, made more urgent by climate-change predictions of increasingly unreliable rainfall patterns into the future. We have a key team of participants on campus including doctoral candidates Scott McAdam and Madeline Murphy working on evolutionary processes in stomatal and leaf vein systems and Heidi Zimmer working on drought tolerance of conifers. Additionally we are linked with group of Australian collaborators who have become involved with different aspects of the project, including Prof. Taylor Field (James Cook University, leaf vascular evolution), Assoc. Prof. Brendan Choat (University of Sydney, global patterns of xylem cavitation), Dr. Chris Blackman (Macquarie University, drought limits to Australian woody plants) and Dr. Meisha Holloway Phillips (ANU, water use in grasses). As is crucial for a project addressing questions of global significance we have a network of international collaborators (see below), and field sites that span Australia and the globe.

We are moving progressively towards our goals of building a global picture of the mechanisms behind plant death or adaptation in response to water stress. In the last 2 years we have produced major discoveries that are published in the best scientific journals including Science, PNAS, Ecology Letters, The Plant Cell, Proceedings of the Royal Society London and New Phytologist.

During 2010-present we have published 20 papers and have another 5 in press. These include papers in Science, PNAS, Plant Cell, Proceedings of the Royal Society London, Ecology Letters, New Phytologist, Oecologia, Plant Physiology, Plant Cell and Environment and others (see WARP for details).

Members (External)

Assoc. Prof Tim Brodribb (Future Fellow UTAS; Project Leader)

Prof. David Bowman (UTAS, Callitris drought sensitivity)

Assoc. Prof John Ross (UTAS, Hormone responses to water stress)

Assoc. Prof Greg Jordan (UTAS, Drought evolution in the Proteaceae)

Dr. Chris Blackman (Macquarie University, linking anatomy and drought tolerance)

Dr. Meisha Holloway-Phillips (ANU, improving grain crop drought performance)

Assoc. Prof. Brendan Choat (University of Sydney, global patterns of xylem vulnerability)

Assoc. Prof Taylor Field (JCU, Leaf vein evolution)

Prof. Kunfang Cao (China, Xishuangbanna Tropical Gardens, drought repair in bamboo)

Prof. Herve Cochard (France, INRA- Xylem cavitation and drought)

Prof. Jody Banks (USA, Purdue University, ABA function during water stress in ferns)

STUDENTS

Scott Mc Adam (UTAS, PhD) Madeline Murphy (UTAS, PhD) Adam McKiernan (UTAS, PhD), Heidi Zimmer (Monash, PhD).