Gibberellins

What are Gibberellins?

Gibberellin is a phytohormone that is involved in growth promotion. Gibberellins have been found in hundreds of species, including fungi and higher plants. Produced in the chloroplasts via the terpenoid pathway, they are transported to the endoplasmic reticulum and cytoplasm after production, until their biological activation. More then 70 types of giberllins are present. GA3 is a extensively researched plant growth regulator....

Historical Discovery of Gibberellins

Gibberellins were first discovered in the 1920s by Japanese scientist Eiichi Kurosawa while studying “bakanae” or foolish seedling disease in rice, caused by the fungus Gibberella fujikuroi. Subsequent research identified gibberellins as the growth-promoting compounds produced by the fungus, leading to the understanding of their role in plant development....

Structure of Gibberellins

Numerous areas of the plant produce distinct forms of gibberellin molecules. There are currently more than 100 distinct gibberellin molecules. These chemicals are produced by the plant in a variety of cell types, although they tend to accumulate in the roots. As opposed to auxin, which concentrates at the apex, this is different. Gibberellin is a diterpenoid, a well-known and frequently occurring chemical in biochemistry. It serves as the building block for compounds like vitamins A and E. Below is the structure of gibberellin A1, also regarded as the first found gibberellin:...

Gibberellins Functions

The plant hormone is responsible for a variety of functions, as mentioned below:...

Mechanism of Action

Gibberellins (GAs) act through a complex signaling pathway to regulate plant growth and development. When gibberellins bind to their receptor, GID1, this complex interacts with DELLA proteins, which are growth repressors. The binding triggers the degradation of DELLA proteins via the ubiquitin-proteasome pathway, relieving their inhibition on growth-promoting genes. This degradation allows for the transcription of GA-responsive genes, promoting processes such as stem elongation, seed germination, and flowering. The precise regulation of this pathway ensures that plants can adapt their growth in response to internal signals and environmental cues, optimizing their development and reproductive success....

Uses of Gibberellin

Considered to have a main role in driving the green revolution, gibberellin finds its use in a wide range of applications as listed below:...

Agricultural Applications of Gibberellins

Gibberellins promote stem elongation, leading to taller and more robust plants. They break seed dormancy, hastening germination and ensuring uniform crop establishment. Gibberellins enhance fruit size and quality in crops like grapes, apples, and citrus. They regulate flowering time, ensuring synchronized blooming and fruit set in crops such as rice and wheat. Gibberellins induce parthenocarpic fruit development, leading to seedless varieties. In horticulture, gibberellins are used to produce ornamental plants with desired traits like elongated stems or enhanced flowering....

Conclusion: Gibberellins

In conclusion, gibberellins are essential plant hormones with diverse roles in growth and development. From promoting stem elongation to enhancing fruit quality, their agricultural applications are profound. Understanding gibberellin mechanisms offers promising avenues for optimizing crop yield, quality, and overall agricultural productivity....

FAQs on Gibberellins

Who made the Initial Discovery of Gibberellins?...