Past Awardee

Towards a Photosynthesis Workbench - "e-Photosynthesis"

John Whitmarsh

College: Liberal Arts and Sciences
Award year: 2001-2002

Photosynthesis provides the reduced carbon for plant growth. Crop production models typically use simple empirical algorithms to predict photosynthetic carbon gain and other physiological processes. This approach ignores the wealth of mechanistic information now available and it precludes investigating the impact of manipulating individual steps in the photosynthetic process on crop production. Knowledge of photosynthesis and its link to carbohydrate distribution are sufficient that mechanistically based dynamic models are now feasible. Our long-term aim is to develop a crop model that would provide a work-bench for numerical experimentation of impacts of manipulating photosynthesis, with a primary objective of predicting and adapting production to rising atmospheric carbon dioxide concentration. To achieve this we will develop a dynamic model that scales mechanistically based linked differential equations to describe leaf photosynthesis. The leaf model would be simulated in parallel for different leaves to represent the complex dynamic light and microenvironment of the crop canopy. Light and microenvironment would be simulated with our physical canopy microclimate model (WIMOVAC). Finally this dynamic canopy photosynthesis model would be integrated onto a phenologically driven crop growth model (SoyGro). This would be a first step in developing a photosynthesis workbench that would provide: 1) a framework for storing and summarizing the rich informatics of the photosynthetic process across taxa; 2) quantitative description and simulation of the photosynthetic process, with prediction of missing information; and 3) linkage of a carbon production model to real-time measurement of leaf and canopy photosynthesis.