Plants, as the most green thumbed gardeners know, are susceptible to damage in many ways. Many plants will succumb to weather that is too dry or too wet; others will die when temperatures drop below freezing, or when they are placed in soil that is too acidic or saturated with salt water. A key factor in determining whether many plants survive is the plant hormone abscisic acid, which helps plants adapt to a variety of stresses. Recent scientific studies have also indicated it may be beneficial to humans for some diseases.

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Abscisic acid hormone levels can mean the difference between life and death for many plants.

Getting Ready for Winter

Perhaps the best known property of ABA is when plants shed leaves, flowers and fruits at the onset of colder weather. If plants did not take that step -- known as abscission, which is where ABA gets its name -- their branches and leaves would become weighted down with snow and break, or they would require water that is not available once groundwater turns to ice. Abscisic acid tells plants to shut down under such conditions, and that they should stay that way until the arrival of spring.

Bud Protection

When cold weather or other threats strike at a plant, abscisic acid will often send the buds of a plant into dormancy as well. New growth sections of plants will fold in upon themselves to protect such areas from damage until danger has passed. ABA also helps inhibit plants from being fooled into sprouting prematurely when an out of season warm spell occurs.

Watching Out for the Seeds

ABA, in addition to protecting plants, is also essential for the future generations produced by their seeds. Abscisic acid helps plant seeds mature and also ensures that they, like their parent plants, stay dormant when threatened or when conditions are not sufficient for them to survive -- for instance, in weather that is too cold, or due to inadequate water supplies for germination.

Human Uses

In recent years, researchers have wondered if abscisic acid could be beneficial to humans as well. A study completed in 2010 at Virginia Tech suggests that ABA might help people fight various diseases causing inflammation, including diabetes, inflammatory bowel disease, atherosclerosis and inflammatory conditions related to obesity. Researchers also hope that that such information could lead to the development of drugs that may be safer than those currently used to treat such medical conditions.