Plant Hormones - Commercial Use of Plant Hormones (GCSE Biology)
Commercial Use of Plant Hormones
Using Auxins in Agriculture
Auxins have many uses is agriculture and horticulture by harnessing their property in causing the elongation of cells.
Auxins can be used as:
Weedkillers
- Weedkillers are used to kill plants that are pests. Weeds are pests that compete for the nutrients that crops require. Therefore, they reduce the efficiency of farming. Weedkillers reduce the number of weeds, therefore increase the crop yield. Selective weedkillers kill only the pests. They contain auxins that make the weeds grow at too quick a rate, killing the plant. An example of a selective weedkiller is 2,4-D which is a synthetic plant hormone.
Rooting Powders
- Rooting powders are used to increase the growth rates of plants. They have auxins that are used to increase the growth of plants. Plant stem cuttings are dipped in this powder before being potted. This increases the growth of the roots.
To Promote Growth in Tissue Culture
- Auxins are also used in tissue culture. Tissue culture involves growing plants in culture form small cuttings of other plants. The culture is a growth medium in which many growth hormones such as auxins are used. Other nutrients such as glucose and mineral ions will also be present in this culture, to provide the plant with the optimum conditions for growth.
More Substances used in Agriculture and the Food Industry
Gibberellins
- Gibberellins initiate seed gemination. The seeds of plants usually have a period known as dormancy. In this stage, the plant is unable to begin germinating. Gibberellins are hormones that cause the plant to leave the period of dormancy. They work by leading to the production of a carbohydrase enzyme, known as alpha-amylase. This causes the end of the dormancy period in barley seeds. Only a low concentration of Gibberellins are required to cause an increase in the speed of germination.
- Gibberellins also lead to cell elongation. This increase in cell elongation will increase the size of the fruit. Moreover, Gibberellins work to promote the flowering of plants. An example of a gibberellin is Gibberellic Acid.
- Gibberellins can also help produce seedless fruit. Gibberellins can be applied to some unpollinated flowers of some types of fruit. This will cause the fruit to grow but not the seeds e.g. in some citrus fruits. Seedless fruit are called parthenocarpic fruit.
Ethene
- Ethene is involved in cell division and fruit ripening. Ethene, C2H4, is a hydrocarbon, a substance made from carbon and hydrogen. It can be used to speed up cell division in plants. This is important in the food industry. As preservatives are used in many foods, a similar principle is important in the fruit industry. Fruits are harvested unripe, then ethene is given. This is used to speed up the ripening process, after fruits have been transported.
- Ethene can also cause shedding of leaves. When leaves age, they produce ethene which causes cells that connect the leaves to the plant to expand, breaking their cells walls and causing the leaves to shed.
Plant hormones are chemicals produced by plants that regulate various functions, such as growth, reproduction, and response to stress. Some of the most important plant hormones include auxins, gibberellins, cytokinins, abscisic acid, and ethylene.
Plant hormones regulate plant growth and development by controlling cell division and elongation, stimulating root and shoot growth, and regulating the timing of flowering and fruit development. They also play a role in responses to environmental stress, such as drought or extreme temperatures.
Plant hormones are used commercially to increase crop yields, improve the quality of fruits and vegetables, and increase the shelf life of perishable products. They are also used to promote the growth of ornamental plants and to increase the efficiency of plant propagation.
In agriculture, plant hormones are used to promote growth and increase yields in crops. For example, auxins are often used to promote root development in cuttings, while gibberellins are used to increase the size of fruits and vegetables. Cytokinins are used to improve the health and longevity of plants, while abscisic acid is used to regulate plant responses to stress.
In plant propagation, plant hormones play a key role in stimulating root and shoot growth in cuttings and seedlings. They can also be used to control the timing of flowering and fruit development.
In horticulture, plant hormones are used to promote the growth of ornamental plants and to increase the efficiency of plant propagation. For example, auxins are often used to stimulate root growth in cuttings, while gibberellins are used to increase the size of flowers and foliage.
There are some potential drawbacks to the commercial use of plant hormones, including the potential for harm to the environment and non-target species. Overuse of plant hormones can also lead to resistance in plants and reduce the effectiveness of the hormones over time. It is important to use plant hormones responsibly and in accordance with regulations and guidelines to minimize any potential risks.
Still got a question? Leave a comment
Leave a comment