- The gibberellins are plant hormones that, among other things, are involved in stem elongation, seed germination, early development, and flower production.
- There are 126 known natural and synthetic gibberellins found in not only plants, but also in fungi and bacteria.
- Gibberellic acid (GA or GA3), the prototypical gibberellin, is the only hormone named after a fungus.
- Researchers in pre-World War II Japan discovered that the rice pathogen Gibberella fugikuroi produced a substance causing “foolish seedling disease” in young plants. This substance turned out to be gibberellic acid.
- If GA is applied to a plant it generally results in rapid stem elongation with increased inter-nodal distance.
- Dwarfism in a plant is often, but not always, caused by a genetic defect in the pathway for GA production.
- The dwarf-tall trait in pea plants that Gregor Mendel studied to unravel the basic laws of genetics results from either a defective or properly functioning gene coding for a protein required for the synthesis of GA.
- GA is an “anti-inhibitor.” It binds to other molecules inside the cell to prevent them from inhibiting the activation of specific genes. This allows the gene to be “turned on” to produce its product.
- GA is used commercially in some countries to control plant development. For example, to delay fruit ripening.
- Since the activity of GA is quite powerful, the amount found in plants is relatively low. However, some studies indicate that concentrated GA is a carcinogen.
10 Facts on Gibberellins
Takeaway: Not just a fun word to say, gibberellins are crucial in the natural process of breaking dormancy and other aspects of germination. Philip McIntosh provides some insight into the world of gibberellins.