Gibberellin

From WikiMD's Wellness Encyclopedia

Gibberellin A1 v2
Gibberellic acid
Ent-Gibberellane
Ent-Kauren
The effect of Gibberellins

Gibberellin refers to a group of plant hormones that regulate various aspects of plant growth and development, including germination, stem elongation, dormancy, flowering, and leaf and fruit aging. Gibberellins (GAs) play a crucial role in breaking the dormancy of seeds and buds, stimulating the growth of stems and leaves, enhancing the size of fruits, and influencing the production and development of flowers.

Discovery[edit | edit source]

The discovery of gibberellins dates back to the early 20th century in Japan, where scientists were investigating the causes of the "foolish seedling" disease in rice. This disease, which caused the rice plants to grow excessively tall and then collapse, was eventually traced to a fungal pathogen, Gibberella fujikuroi. The active substances responsible for the growth effects were isolated from the fungus and named gibberellins.

Chemical Structure[edit | edit source]

Gibberellins are diterpenoid acids. Over 130 different gibberellins have been identified in plants, fungi, and bacteria, but only a small number of these are biologically active in plants. The most common and biologically active gibberellin found in many plants is gibberellic acid (GA3).

Function in Plants[edit | edit source]

Gibberellins have a wide range of effects on plant growth and development, which include:

  • Seed Germination: Gibberellins promote seed germination by breaking seed dormancy, which is achieved by stimulating the production of enzymes that degrade the seed's storage materials, providing energy for the growing embryo.
  • Stem Growth: They are responsible for stimulating cell elongation and division, which results in taller plants.
  • Flowering: Gibberellins can influence the flowering process, including the induction of flowering in some long-day plants and biennials.
  • Fruit Development: They are involved in the growth and development of fruits, often leading to larger fruit size.
  • Leaf Growth: Gibberellins promote the expansion of leaves.

Applications in Agriculture[edit | edit source]

Due to their growth-promoting effects, gibberellins have various applications in agriculture. They are used to improve fruit size in crops like grapes and oranges, to induce uniform flowering and fruit set in certain plants, and to break the dormancy of seeds to synchronize germination.

Environmental and Genetic Regulation[edit | edit source]

The production and activity of gibberellins in plants are tightly regulated by environmental cues such as light and temperature, as well as genetic factors. Plants have developed mechanisms to ensure that gibberellin levels are optimal for their growth and development under varying environmental conditions.

Conclusion[edit | edit source]

Gibberellins are essential plant hormones that play a pivotal role in regulating plant growth and development. Their discovery and subsequent research have not only expanded our understanding of plant biology but also provided tools for improving agricultural productivity.

Gibberellin Resources

Contributors: Prab R. Tumpati, MD