Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air insi ....Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air inside leaves based on stable isotope analysis of carbon dioxide and water vapour exchanged between leaves and air. The project is expected to provide fundamental knowledge about how stomata regulate photosynthesis and water use, with significant implications for modelling vegetation function and for improving the performance of crop plants.Read moreRead less
On the physiology of plant transpiration. This project aims to better understand plant transpiration. It is significant from both a basic and a practical perspective. It intends to solve a conundrum of the biophysics of the evaporative sites within leaves. That is, in dry air, the relative humidity of intercellular air spaces suggests much lower liquid water potentials than those typically measured. At a practical level, the failure to sustain transpiration in dry conditions leads to desiccation ....On the physiology of plant transpiration. This project aims to better understand plant transpiration. It is significant from both a basic and a practical perspective. It intends to solve a conundrum of the biophysics of the evaporative sites within leaves. That is, in dry air, the relative humidity of intercellular air spaces suggests much lower liquid water potentials than those typically measured. At a practical level, the failure to sustain transpiration in dry conditions leads to desiccation and tissue death, and plants differ in this vulnerability. The aim is to apply a novel nanoparticle technique to measure the water potential distribution within the leaf, identify hydraulic resilience attributes, and develop a modern theory of optimal transpiration under varying conditions.Read moreRead less
Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots ....Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots to absorb atmospheric water could profoundly affect the diversity, survival and productivity of mangroves where high soil salinity limits water uptake by roots, particularly during hot, dry conditions.Read moreRead less
Interactive effects of salinity and nutrients: linking physiological processes with patterns in mangrove forest productivity. The proposed research will provide insight into physiological mechanisms that underpin mangrove productivity along salinity and aridity gradients, and determine how these factors affect plant responses to nutrient enrichment. Plant traits that increase salt and drought tolerance will be identified, thereby assisting development of plant varieties suited to Australian cond ....Interactive effects of salinity and nutrients: linking physiological processes with patterns in mangrove forest productivity. The proposed research will provide insight into physiological mechanisms that underpin mangrove productivity along salinity and aridity gradients, and determine how these factors affect plant responses to nutrient enrichment. Plant traits that increase salt and drought tolerance will be identified, thereby assisting development of plant varieties suited to Australian conditions. The results will also contribute to development of process-based models to better manage mangrove resources with climate change and increasing nutrient influx from urban or agricultural activities. Such models are essential for managing mangrove productivity for sustainable fisheries, and protecting the ecological well being of the coastal zone.Read moreRead less
The role of drought-stress and insect attack on rainforest plant health. This project aims to examine the vulnerability of tropical plants to drought and insect attack in a large-scale field experiment. We will pioneer a new research approach that focuses on the causes and stages of decline in plant health prior to death, in order to identify the characteristics of plant species that make them more susceptible to drought and insect attack. Expected outcomes of this project include an improved ca ....The role of drought-stress and insect attack on rainforest plant health. This project aims to examine the vulnerability of tropical plants to drought and insect attack in a large-scale field experiment. We will pioneer a new research approach that focuses on the causes and stages of decline in plant health prior to death, in order to identify the characteristics of plant species that make them more susceptible to drought and insect attack. Expected outcomes of this project include an improved capacity to predict the function and composition of future forests. This project will provide significant benefits to communities concerned with the direct and indirect effects of droughts in protected areas, forestry reserves and agriculture. Read moreRead less
How do sunflowers make protein drugs in their seeds? We recently discovered in sunflower the origin of a small protein ring that chemists have used for a decade to base designed drugs upon. This project aims to know how sunflowers make it so we may manipulate other plants to manufacture ring-based drugs.
The new plant hormone controlling shoot branching. This project will create genetic tools and knowledge on the control of a new plant growth hormone that affects a diverse number of plant properties. These important traits include shoot number, water and nutrient uptake, wood production, the ability to generate roots and the ability to stimulate particular potentially devastating parasitic weeds.
Circular Plant Proteins with Pharmaceutical Applications. The proposed research will develop methods for using plants as protein production factories. Initially I will use plants to create engineered cyclotides that incorporate peptides with proven therapeutic activity against cancer and multiple sclerosis. Successful production of therapeutic proteins in plants will benefit Australians by making treatments for these and other diseases more accessible. It also has the potential for a major econo ....Circular Plant Proteins with Pharmaceutical Applications. The proposed research will develop methods for using plants as protein production factories. Initially I will use plants to create engineered cyclotides that incorporate peptides with proven therapeutic activity against cancer and multiple sclerosis. Successful production of therapeutic proteins in plants will benefit Australians by making treatments for these and other diseases more accessible. It also has the potential for a major economic benefit from the sales of Australian-based drugs. This proposal will also provide outstanding research training for graduate students in multidisciplinary methods that constitute state-of the-art structural and plant molecular biology.Read moreRead less
Will stomatal responses to humidity and carbon dioxide constrain tropical forest productivity as atmospheric carbon dioxide rises? This project will investigate two physiological processes that will partly determine growth responses of tropical forest trees to rising atmospheric carbon dioxide. The project will produce equations summarising physiological responses that can be incorporated into process-based models of tropical forest productivity.
Response and vulnerability of tropical rainforest plants to experimental drought. This project will assess the vulnerability of rainforest plants to a large-scale experimental drought in the Daintree rainforest of north Queensland, using a canopy crane to access all vertical forest layers. This will provide a unique opportunity to understand how rainforests could be affected by future climate change.