Are hemicelluloses mobile carbon reserves in plants?

The project aims at clarifying the question, whether or not hemicelluloses in vegetative plant organs contribute to a plant's carbon reserve pool. Many studies described the structural diversity of hemicelluloses and their position within the cell-wall. But despite representing the second most abundant polysaccharide in nature, we do know little about the ecophysiological significance of hemicelluloses. Previous works suggested that hemicellulose concentrations of mature plant tissue do change with changing environmental conditions, indicating that at least some fractions of a plant's hemicellulose pool are mobile. An unequivocal proof, however, is still missing. The project thus will evaluate the possible role of hemicelluloses for mobile carbon storage of plants by measuring hemicellulose pools at the ecosystem level, and by experimentally changing the carbon source-sink relations of plants in order to assess the extent of mobility within the hemicellulose pools. Because of the abundant distribution of hemicelluloses in plants, the results of the proposed study will be of interest for all studies dealing with carbon relations in plants. If hemicelluloses should indeed proof as mobile carbon pools, the classical view of carbon storage in plants as a whole would have to be re-evaluated.

Funding: Swiss National Science Foundation (SNF), project Nr. Nr. 3100A0-17548

Duration: 2005-2009

Christina Schädel (University of Basel)
Andreas Richter (University of Vienna)
Andreas Blöchl (University of Vienna)