It’s important to know the growth pattern of different crops you have on your farm.

Such knowledge helps to understand when there are fungal infections that call for fungicides.

What if you could influence the growth pattern of a plant? Well, that’s possible. And that’s what brings us to plant growth regulators (PGR) otherwise called plant hormones.

If you are searching for PGR products for your plants, then this is a must-read guide for you.


I am going to tell you about what are plant growth regulators and the PGR examples.


So What are Plant Growth Regulators?

These are chemical substances that influence a plant’s growth pattern and the formation of organs, tissues, and cells.

Knowing the various plant hormones allows you to choose the right chemicals to apply to achieve the desired outcome

For example, it will enable you to control the quality and the number of leaves to harvest from a crop.

So here are the top plant growth regulators;


1.   Auxins,IAA.

The auxins, plant growth regulators are also called indole acetic acid, IAA.  These exist both as natural and synthetic hormones and stimulates the elongation of the cells.

In plants they are manufactured mainly in the following regions;

  •    Shoot tips and tender leaves
  •    In developing flowers and seeds
  •    Embryos.

The Auxins are characterized by the polar downward movement. Such a downward movement on the shoots is described as basipetal

On the other hand, the downward motion in the roots is termed as an acropetal.

The hormones play a significant role in the plants’ growth cycle.


As one of the plant growth hormones, the auxins have a wide range of horticultural and agricultural usage;

Some plants are easy to grow using the cuttings.

So if you want such a planting material to develop roots quickly, an application of these hormones aids that process.

But to other plants like pineapple, it enhances the quick development of flowers and fruits.

However, the synthetic auxins are used as herbicides that help in selective weed control.

For instance 2, 4-dichlorophenoxyacetic acid can be used to kill all broad leaves while leaving the thin leaves unaffected

So if you desire to maintain the beautiful lawn free from weeds, the selective weed killing property of auxins comes into use,

When you experience the bumper harvest of potatoes, storage can become a problem. With time the potatoes start to sprout.

But not so when you have the Auxins group of hormones, for example, the (NAA). You can use them to discourage the sprouting of potatoes during storage.

2.    Cytokinins

These play a pivotal role in the cell division and inducing shoots budding. So whereas auxins discourage budding, the Cytokinins enhance.

In plants, they are found in the active cell division zones such as the fruits, root tip, seeds, and leaves.


Their major role in plants growth is the development of new leaves, chloroplasts, and the growth of lateral shoots

Just like we would wish to delay aging, a farmer would also wish to extend the lifespan of his crops. Prolonging the lifespan of your fruits or vegetation mean more years of farm produce.

So to the crops, the cytokinins play that vital role of delaying the aging of plants. It does that by encouraging plant cells’ division.

They ensure that your plant remains youthful and thrive in life.

And do plants get wounded? Yes they do and to assist in the quick repair and regeneration, the cytokinins and the auxins plays the active role.

So by shifting the concentration of the cytokinins and the auxins in a plant you can influence the development of roots or shoots.


3.    Ethylene

Its one of the rare plant growth regulators that is gaseous in form. Unlike other plant hormones which are produced at specific parts, the gaseous hormone is produced in any part of the plant.

After is production it’s then transported to other parts and even diffuses through the air.

Its major role is influencing the ripening of fruits and the rotting in plants. The gas is mainly secreted by the plant at the fruiting stage.

Also when a plant is subjected to a lot of stress, more volume of ethylene hormones are produced. For example following a cut, the ethylene gas also helps to heal the wound quickly.


Owing to its ability to influence the ripening of fruits, the growth hormone finds practical application when transporting fruits.

For the gas hormone to be formed, oxygen is needed. Thus trucks transporting fruits have pressurized low oxygen but high carbon dioxide storage facilities

By so doing, the fruits reach their remote destination when they haven’t over ripened.  On the other hand, the gas can be sued to induce ripening in fruits.


4.   Gibberellin, GA

Have you ever desired to have plants with longer stems? That can be useful especially to the sugarcane farmers.

Well, that is what the chemical substance named gibberellins does to your plants. So when you spray the chemical on your sugarcanes, they develop elongated stems.  They have large spaces between the nodes.

And do you know what longer internodes mean; larger capacity for storing sugar? So when you spot that dwarfed, closely packed nodes sugar cane in your farm, you know exactly

The chemical substance exists in many forms; typically over 100.


The knowledge on the role of GA in plant growth finds its use in stem elongation of plans, e.g., sweet corn, tomatoes or sugarcane.

Besides, it also helps to enhance seed germination, and induce the tubers sand buds to growth too. When applied appropriately it helps to grow plants with larger leaves and flowers or even seedless fruits.

Cabbage and beet farmers, therefore, find it vital in inducing bolting in the plants. Also when you desire the quick formation of seeds, Gibberlin can help you achieve that easily from your plants.


5. Abscisic acid, ABA

The ABA is the growth hormone with development inhibiting ability.  It suppresses the growth and the germination of seeds.

As the suppressive growth hormone, it encourages the dormancy of buds and the falling of leaves.

It has the reverse effect of cytokinins and gibberellins.

During the stressing moments like drought, the Abscisic acid acts as the alert to the whole parts of the plant of the water shortage condition.

As a result, the plant develops strategies to cope with the distress of water like dropping of leaves, limiting growth and closing of stomata.


The hormone finds typical use in encouraging plants to develop resistant to harsh climatic conditions.



There you have the glimpse of the plant growth regulators.

So when you employ the right plant hormones to the correct use of pesticide on your farm, you are closer to reaping the bumper harvest.


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