Gibberellic acid
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Gibberellic acid (abbreviation: GA3), also called Gibberellin A3 is a hormone found in plants. Its chemical formula is C19H22O6. It has the appearance of a white to pale yellow crystalline powder with melting point 233-235 °C (decomposes). It is soluble in ethanol and slightly soluble in water.
Gibberellic acid is a simple gibberellin, promoting growth and elongation of cells. It affects decomposition of plants and helps plants grow if used in small amounts, but eventually plants grow a tolerance for it. Gibberellic acid stimulates the cells of germinating seeds to produce mRNA molecules that code for hydrolytic enzymes. Gibberellic acid is a very potent hormone whose natural occurrence in plants controls their development. Since GA regulates growth, applications of very low concentrations can have a profound effect while too much will have the opposite effect. It is usually used in concentrations between 0.01-10 mg/L.
It was first discovered in Japan in 1935 as a result of the study of a condition common in rice plants called "foolish seedling" disease, which caused the plants to grow much taller than normal. The effects of gibberellins weren't widely understood until years later.
Gibberellins have a number of effects on plant development. They can 1) stimulate rapid stem growth, 2) induce mitotic division in the leaves of some plants, 3) increase seed germination rate. Gibberellic acid is sometimes used in laboratory and greenhouse settings to trigger germination in seeds that would otherwise remain dormant.