Some plants can survive almost total dehydration. Ronald Balsamo and Bradley Layton of Villanova University and Drexel University respectively, and their colleagues, have been studying a plant known as the ‘resurrection fern’ (Polypodium polypodioides) that can survive a 95% loss of water. For reference, corn (maize) will die from a 20 to 30% loss of water. Humans can develop symptoms of dehydration after losing only 2% of our water.
The scientists discovered that the ferns contain large amounts of a class of proteins aptly named ‘dehydrins’. These extremely hydrophilic molecules cluster near the plant’s cell walls, attracting what little water is left to those areas. In this way, the dehydrins appear to act as a lubricant, preventing the plant cells from becoming too brittle.
The researchers hope that by transferring the dehydrin gene to crops, they’ll be able to increase the drought resistance of those plants.