Plants give up some deep secrets of drought resistance
Figuring out how to trigger a dormant state, such as exists naturally in seeds, which are 10 percent water and can in some cases remain viable for hundreds of years, could be key to creating plants that survive drought in the field, Sussman explains.
The new study, published today (Aug. 23) in the Proceedings of the National Academy of Sciences, identifies the protein targets in cells of a key hormone that controls how plants respond to environmental stresses such as drought, excessive radiation and cold.
The work, which builds on decades of research with a key plant hormone known as abscisic acid, could help underpin the development of new crop plant strains capable of thriving in hotter, dryer climates. The work is considered important in light of the pressing need to expand and intensify agricultural production on marginal lands worldwide, and especially so in the context of global climate change.
"If we can figure out how this works with crops and make them able to resist drought, the benefits would be enormous," notes Michael Sussman, a UW-Madison professor of biochemistry and the senior author of the new study. "These are the first baby steps to understand the effects of dehydration in plants and it may give us the opportunity to develop crops that can withstand this kind of stress in the field."
Working in the model laboratory plant Arabidopsis, the Wisconsin team explored the influence of abscisic acid, a long-studied hormone that, in addition to influencing how plants respond to environmental stress, controls the naturally occurring processes of seed dormancy and germination.
The hormone has been known to science for 50 years, and was believed to influence certain proteins in cells in a complicated cascade of events that aided the ability of a plant to survive such stresses as dehydration, excessive radiation and cold temperatures. But any plant cell, Sussman explains, contains at least 30,000 different proteins, and the identity of the few proteins activated by the hormone was a deep mystery.