Genetic and Hormonal Regulation of Plant Growth. Leguminous plants make a substantial contribution to the Australian economy. To ensure future growth, we need to know more about how legume development is regulated. Genetic mutants, typically affecting the growth-promoting gibberellin plant hormones, played a key role in the green revolution, which transformed agriculture world-wide. Recent results show that gibberellin acts in concert with another hormone, auxin. We will generate new auxin-relat ....Genetic and Hormonal Regulation of Plant Growth. Leguminous plants make a substantial contribution to the Australian economy. To ensure future growth, we need to know more about how legume development is regulated. Genetic mutants, typically affecting the growth-promoting gibberellin plant hormones, played a key role in the green revolution, which transformed agriculture world-wide. Recent results show that gibberellin acts in concert with another hormone, auxin. We will generate new auxin-related mutants that will help us to understand how auxin and auxin-mediated interactions affect crop architecture and performance. Further benefit will accrue from training of students in state-of-the-art techniques, and the generation of new germplasm for use by other researchers and plant breeders. Read moreRead less
Genetic and Hormonal Interactions Controlling Shoot Growth. This project will determine how plant growth is regulated at the genetic, biochemical, and physiological levels, and how plant hormones provide key links between the genotype and overall phenotype (phenome). The work uses peas as a model because of the wealth of mutants available and the suitability of the species for physiological and biochemical studies. Our results will allow comparison of development in the caulescent pea plant wi ....Genetic and Hormonal Interactions Controlling Shoot Growth. This project will determine how plant growth is regulated at the genetic, biochemical, and physiological levels, and how plant hormones provide key links between the genotype and overall phenotype (phenome). The work uses peas as a model because of the wealth of mutants available and the suitability of the species for physiological and biochemical studies. Our results will allow comparison of development in the caulescent pea plant with other model species with different growth habits, such as Arabidopsis. The project is significant because it will enable shoot growth to be modified either genetically or chemically to meet particular agronomic objectives.Read moreRead less
Development and regulation of thermogenesis in thermoregulating flowers. Flowers of certain primitive plants produce enough heat to raise their temperatures up to 40 C above the air, and regulate it at a nearly constant level. Like warm-blooded mammals, the flowers increase heat production as environmental temperature falls. However, they thermoregulate on a cellular level, unlike mammals with their complex nervous system. We aim to elucidate the mechanisms involved in regulation of heat-prod ....Development and regulation of thermogenesis in thermoregulating flowers. Flowers of certain primitive plants produce enough heat to raise their temperatures up to 40 C above the air, and regulate it at a nearly constant level. Like warm-blooded mammals, the flowers increase heat production as environmental temperature falls. However, they thermoregulate on a cellular level, unlike mammals with their complex nervous system. We aim to elucidate the mechanisms involved in regulation of heat-production, with molecular, biochemical and stable isotope techniques. We will investigate spatial and temporal patterns of gene expression and activity of putative regulatory enzymes. The results will have implications for human physiology and agriculture.Read moreRead less
Brassinosteroids and Plant Development. Brassinosteroids are steroid hormones, which are essential for normal plant growth and development. This project will address fundamental questions regarding the biology of these substances. The work uses pea as a model species because of its suitability for physiological, biochemical and genetic studies. The results obtained will substantially increase our knowledge of the way in which these substances regulate plant growth. This is significant as it will ....Brassinosteroids and Plant Development. Brassinosteroids are steroid hormones, which are essential for normal plant growth and development. This project will address fundamental questions regarding the biology of these substances. The work uses pea as a model species because of its suitability for physiological, biochemical and genetic studies. The results obtained will substantially increase our knowledge of the way in which these substances regulate plant growth. This is significant as it will ultimately allow plant growth to be modified either genetically or chemically, to meet particular agronomic objectives.Read moreRead less
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
Calcium compartmentation in leaves: testing an integrated model of water and calcium transport with cell specific functional genomics. Calcium is a vital nutrient to animals and humans and its storage in vegetation is important for its accessibility. We believe this storage is linked to water flow in the leaf by a novel mechanism. This project will provide fundamental understanding of the cell type-specific processes involved in calcium storage and water flow in plants. High calibre PhD and Hono ....Calcium compartmentation in leaves: testing an integrated model of water and calcium transport with cell specific functional genomics. Calcium is a vital nutrient to animals and humans and its storage in vegetation is important for its accessibility. We believe this storage is linked to water flow in the leaf by a novel mechanism. This project will provide fundamental understanding of the cell type-specific processes involved in calcium storage and water flow in plants. High calibre PhD and Honours students will be educated to maintain the momentum of international excellence within Australia in the field of plant nutrient relations. The increase in understanding will allow future work to improve calcium availability and water use by plants to the benefit of agricultural productivity and quality of life.Read moreRead less
Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will cap ....Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will capitalize on our progress in describing the functional genetics of this process and aims to elucidate the mechanism of active CO2 uptake and the way that cells sense the ambient CO2 concentration. The information gained is likely to be useful for designing improved crops.Read moreRead less
Feasting on protein? Strategies of organic nitrogen acquisition by plant roots. Crops require large amounts of nitrogen for growth. Application of nitrogen fertiliser enhances yield, but causes off-site nitrogen pollution, a main threat to ecosystem integrity. Most nitrogen in soil occurs as organic complexes that are broken down by soil organism into small compounds, which are taken up roots or lost from the soil. This project will generate fundamental knowledge of how an Australian species and ....Feasting on protein? Strategies of organic nitrogen acquisition by plant roots. Crops require large amounts of nitrogen for growth. Application of nitrogen fertiliser enhances yield, but causes off-site nitrogen pollution, a main threat to ecosystem integrity. Most nitrogen in soil occurs as organic complexes that are broken down by soil organism into small compounds, which are taken up roots or lost from the soil. This project will generate fundamental knowledge of how an Australian species and a crop species with unusual root specialisations access soil organic nitrogen, thus increasing the efficiency of nitrogen use and reducing nitrogen loss. The research employs cutting-edge techniques for sustainable resource use, improved efficiency of crops and farming systems, and preservation of Australia's biodiversity.Read moreRead less
Tree-mediated methane fluxes: A new frontier in the global carbon cycle. Methane is an extremely potent greenhouse gas. Recent evidence suggests that tree-mediated fluxes may be a significant, but overlooked source of methane to the atmosphere. This project aims to quantify the magnitude and drivers of tree-mediated methane fluxes from Australia’s dominant forest types. Innovatively, we will be using a novel combination of empirical field based measurements, gas tracer experiments, microbial ana ....Tree-mediated methane fluxes: A new frontier in the global carbon cycle. Methane is an extremely potent greenhouse gas. Recent evidence suggests that tree-mediated fluxes may be a significant, but overlooked source of methane to the atmosphere. This project aims to quantify the magnitude and drivers of tree-mediated methane fluxes from Australia’s dominant forest types. Innovatively, we will be using a novel combination of empirical field based measurements, gas tracer experiments, microbial analysis and modelling methods. Expected outcomes are a mechanistic understanding of tree-mediated methane fluxes, helping to constrain regional, national and global methane budgets. The results of this study will help inform publicly funded greenhouse gas abatement strategies, ensuring a maximal return on investment.Read moreRead less
Integrated genetic regulation of photomorphogenesis in Pisum. This project will use a molecular genetic approach in garden pea to investigate the roles of photoreceptors that mediate developmental responses to light. It will define gene families encoding phytochrome, cryptochrome and phototropin photoreceptors, characterise photoreceptor gene expression, and identify mutants with impaired response to light. The mutants will be used in molecular, physiological and biochemical studies to examine h ....Integrated genetic regulation of photomorphogenesis in Pisum. This project will use a molecular genetic approach in garden pea to investigate the roles of photoreceptors that mediate developmental responses to light. It will define gene families encoding phytochrome, cryptochrome and phototropin photoreceptors, characterise photoreceptor gene expression, and identify mutants with impaired response to light. The mutants will be used in molecular, physiological and biochemical studies to examine how photoreceptors control and co-ordinate development throughout the plant via effects on plant hormone synthesis and response. Results from the project will be of practical importance in manipulating key aspects of plant growth to better suit particular environmental and agronomic objectives.Read moreRead less