Stomatal-based systems analysis of water use efficiency

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

We will incorporate transpiration and carbon fixation explicitly within the OnGuard software, and will test, by in silico modelling and experimental validation, the hypothesis that significant erosion in the efficiency of water use by plants arises because of the mismatch in environmental responses between stomata and photosynthesis. These studies will explore also the connection to oscillations known to occur in stomatal aperture and in the signalling events (e.g. cytosolic-free [Ca2+]) previously documented at the cellular level in single guard cells and reproduced in the first-generation OnGuard models. The modelling and experimental methods proposed are independent, but their combination gives added value to both. Model development will incorporate recent advances in Bayesian inference to enable fast, automated searching for computational solutions. These are proven methods and naturally compute the confidences in model predictions and their relation to observed data. Bayesian methods also address questions such as 'Which parameters are critical to defining a specific set of behaviours?', questions that are important in directing model development. The experimental work will build on methods at the research forefront in analysing water use efficiency in real time from single plants and in scaling for data capture in the field by eddy flux (covariance) and stable isotope discrimination analysis. Experiments will assess stomatal response to light, humidity and CO2 to extract stomatal kinetics and their association with oscillations in transpiration and carbon assimilation. We will use these data to parameterise models and to test the micro-macro link of the models in predicting transpiration and water use efficiency. Thus, we fully expect new and exciting insights into the behaviour of stomata in the leaf and crop canopy, much as our previous modelling efforts provided hitherto unexpected insights into the physiology of the isolated guard cell.

This proposal is for fundamental research developing new concepts at the core of ideas emerging within the international plant and systems biology communities. The research will stimulate thinking around strategies for systems modelling, especially in relation to membrane transport, plant growth, development and pathology, and it should facilitate in silico methodologies for approaching crop engineering. Thus, the research is expected to benefit fundamental researchers as well as agriculture and industry through conceptual developments as well as the introduction of new computational technologies for the analysis of plant water use efficiency and productivity. The research will feed into higher education training programmes through capacity building at the postgraduate and postdoctoral levels. Additional impact is proposed through public displays and the development of teaching resources building on the background work for this proposal. Finally the research will help guide future efforts in applications to agricultural/industrial systems. The applicants have established links with industrial/technology transfer partners and research institutes to take advantage of these developments. Further details of these, and additional impacts will be found in Part 1 of the Case for Support and in the attached Impact Pathways.