Cheatgrass, on the other hand, runs the protein biosynthetic pathway full out under all conditions. It seems to lack a switch or control system.
Soybeans, in other words, are optimized for the low carbon dioxide concentrations and abundant water that were common over the last half million years.
Cheatgrass, however, evolved in arid conditions where it made sense to strengthen water transport tissues.
Unfortunately, the climate of the future is likely to be more like the one to which cheatgrass is adapted.
"We believe," says Schaefer, "that as carbon dioxide rises and we try to farm more marginal land to feed a burgeoning population, plants like cheatgrass will have a large advantage over plants like soybeans."
In 2006, the University of Illinois at Urbana-Champaign, published the results of an experiment where soybeans were exposed for four months to carbon dioxide released under computer control on the upwind side of a field plot.
The experiment showed that soybeans benefited much less from elevated carbon dioxide levels than earlier experiments in greenhouses and laboratories had suggested they would.
Schaefer believes his work shows why.
|Contact: Diana Lutz|
Washington University in St. Louis