Plant hormones are complex organic substances. The trees that form in the plants at certain places. And from there they are transferred to different parts of plants through vascular tissue and control their growth and metabolic activities.
The word hormone means stimulating substance
Types of plant hormones
Types of plant hormones and their functions
There are two types of plant hormones
- Growth aids hormones
- Anti growth hormones
A. Growth aids hormone
B. Anti growth hormones
- Abscisic acid
Auxin hormones are produced at the top of plants. These hormones mainly induce elongation in plant cells.
The auxin hormone was discovered by Bent in 1928.
use or function
They control the tracking and Gurutwanuwartn movements of plants.
- positive phototropism
- negative phototropism
- top influencer
- Oxygen hormone acts as a value induction.
- It prevents wilting of fruits.
- These investors drive the function. Or with its effect, the necrotic function can be done more easily.
- Oxygen to kill weeds in fields
- (2.4) Dichloro finoxa acetic acid is used.
- Flowering – In some plants it induces flowering.
examples of oxygens
indole acetic acid ( IAA)
indole butyric acid (IBA)
Indole 3 Pyruvic Acid (I3PA)
Gibberellins hormones are produced in the upper extremities and embryos of plants and control growth in all parts of the plants.
Gibberellins were discovered by Kurosawa scientist in 1926. Yabuta and Hayashi isolated this substance from fungi.
Uses and Effects of Gibberellins
- These help in increasing the length of the plants.
- Gibberellins increase the length of the mountain cells. which is called bolting.
- For example, in maize, peas, beetroot and genetically dwarf plants grow tall when gibberellin is sprinkled.
- Gibberellins are used to speed up the process of nutrition in late flowering plants.
- Through this seedless fruits can be obtained without fertilization.
- By its use, the dormancy period of Calgibrelin in seed and potato tubers can be reduced.
- With its use, the leaves of peas, beans, tomatoes, etc., become maximum wide.
- This hormone is useful in controlling the use of senescence, development of flowers and fruits, etc.
- Cytokinins induce cell division
- Chemicals that induce cell division are called cytokinins
- Miller and his colleagues obtained it in 1956 from the DNA of yeast and named it kinetin.
- Sakug 1965 found coconut water similar to kinetin, he called these substances kininins, which were later named cytokinins. Latham isolated cytokinins from corn seeds and named it zeatin.
Effects and Uses of Cytokinins
Accelerates the rate of cell division by taking it along with oxygen
It controls the formation of plant organs
Its use accelerates the growth of buds in Parv
It shortens the presentation time
Light-loving seeds treated with cytokinin can be grown in darkness
It increases the number of female flowers
Root torture or both can be developed by changing the ratio of the amount of cytokinins and oxygens.
cytokinins can inhibit malignancy.
Cytokinins are also used to increase the immunity of plants.
abscisic acid is an anti-growth hormone, it stops cell division, hence it is called resistance hormone.
Isolated from flower cells of cotton plant in 1961 – 1965 by Colors and Advocate
Abscisic acid effects and uses
- By spraying its solution on the leaves, life is generated in the leaves.
- This cell division prevents cells from elongating.
- It inhibits the growth of buds and germination of seeds.
- Inhibits nutrition in plants.
- It reduces transpiration by closing the spores.
- Light-loving seeds treated with cytokinin can be grown
It is the only hormone that occurs naturally in the gaseous state and acts as an resistive agent.
Which was discovered by Berg in 1962 as a plant hormone. Its beauty increases during the ripening of the fruit.
Effects and Functions of Ethylene
- It helps in ripening of fruits.
- This prevents the plants from growing tall.
- Due to its effect the number of female flowers increases while the number of male flowers decreases.
- It reduces flowering.
- It trumps the separation of rows, fruits and flowers.
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