Plants can change the direction of the roots and grow away from saline areas. Researchers at the University of Copenhagen helped figure out what makes this possible. The discovery changes our understanding of how plants change their shape and direction of growth and could help alleviate the growing global problem of high soil salinity on farmland. Phys.org portal.
Unfortunately, salt on agricultural land is a growing global problem, due in part to climate change, which increases soil salinization whenever floods hit coastal areas. As a rule, this reduces crop yields.
Scientists have discovered what exactly happens inside plants at the cellular and molecular level when their roots grow away from salt. The results were published in the scientific journal Developmental Cell.
The research team found that when a plant senses a localized salt concentration, it activates the stress hormone ABA (abscisic acid). This hormone then activates the response mechanism.
This hormone causes the tiny protein tubes in the cell, called the cytoskeleton, to reorganize. The reorganization then causes the cellulose fibers surrounding the root cells to undergo a similar rearrangement, causing the root to twist in such a way that it grows away from the salt.
The leading role played by the stress hormone makes the discovery unexpected for researchers. Until now, it was believed that the hormone auxin controls the plant's ability to change direction in response to various environmental stimuli (known as tropisms).
That the stress hormone ABA is critical to the ability of plants to reorganize their cell walls and change the shape and direction of growth is completely new. This could open up new avenues in plant research, where more attention will be paid to the important role the hormone seems to play in the ability of plants to cope with different conditions by changing movement.
It will be some time before new knowledge is applied to agriculture - not least because GMOs remain banned in the EU. However, the results may pave the way for more salt-tolerant crop varieties.