Tues Mar 3 // Simulating an environmentally responsive plant by incorporating mechanisms responsible for allocation
University of Illinois
The allocation of resources to roots and shoots can greatly alter total plant mass. Allocation is thought to be a consequence of growth processes (i.e. uptake rates, transport rates, growth rates) and the communication between them via signaling mechanisms. Changes in the environment create imbalances in carbon and nitrogen concentrations in the plant. These imbalances induce internal feedbacks that alter key growth processes but how they function together to define allocation remains unclear. Here, the mechanisms responsible for allocation are investigated by creating a model of carbon sensitive and nitrogen sensitive feedbacks on growth processes. The extent to which the model responds to changes in carbon and nitrogen availability is evaluated by simulating a combination of two atmospheric CO2 and two soil nitrogen treatments along with an additional test of defoliation on leaf mass. Overall this shows that a combination of known signalling mechanisms are sufficient to reproduce experimentally observed responses to external resource availability.