The Effects of Gibberellic Acid on Germinating Barley

Features

• Gibberellins are a class of plant hormones that fulfill important roles in germination and fruit growth. One of the most important gibberellins is gibberellic acid. Applying gibberellic acid to dormant barley seeds can stimulate germination.

Function

• Inside the developing seed, the embryo releases gibberellins like gibberellic acid in response to environmental stimuli. The gibberellic acid acts on a layer of tissue called the aleurone to trigger secretion of digestive enzymes; these enzymes then hydrolyze or break down starch. This process and the release of gibberellins by the embryo helps trigger germination.

Considerations

• Gibberellins aren't the only plant hormones involved in barley seed germination; another plant hormone called abscisic acid is crucial as well. Abscisic acid acts in opposition to gibberellins by keeping the seed dormant and even down-regulates some of the genes involved in the production of gibberellic acid. Other factors like the amount of available oxygen are crucial to germination as well.