Transgenic Plants

“A transgenic plant is a modified organism where genes are transferred from one organism to another through genetic engineering techniques”.

The purpose of producing a transgenic plant is to obtain a species that has ideal traits, high yield and quality.

Methods Used for Gene Transfer

There are two methods majorly which are used to transfer genes in plants. The two methods include:

1. Agrobacterium mediates gene transfer

Agrobacterium tumifaciens is a plant pathogen. It is known to cause crown gall disease, which is swelling in plants just above the soil level. After infecting the plants, they transfer their genetic material to them, which eventually gets incorporated into the plant genome.

For genetic engineering, the bacterium is incorporated with a Ti plasmid with desirable genes and made to infect the plant.

The Ti plasmid is a tumour inducing circular plasmid, that transfers the host chromosomes to the plants and is also responsible for causing the swelling.

2. Particle bombardment / Gene gun method

As the name suggests, in this method, the desired gene is coated in a gold or tungsten particle and bombarded into the plant cells. Once bombarded, the sequence is incorporated into the plant cells, which can be proliferated by tissue culture methods.

Applications of Transgenic Plants

• Resistance to biotic and abiotic stress: Biotic stress is imposed on plants as a result of the action of living beings such as viruses, bacteria, pests and pathogens. To relieve the plants from such stress they are incorporated with disease-resistant genes, which gives a better yield and quality to the crops.
• Abiotic stress, as a result of changes in the environment, causes great damage to the plants. Soil composition, humidity, water level, and temperature are important factors for plant growth. Due to changes in the climate, all the factors seem to be altered. Thus, plants are incorporated with stress-tolerant genes for better production.
• Increased nutritional value: Biofortification is the process of increasing the nutritional value of a crop. Malnutrition is a common problem in developing countries. As a solution, plants are engineered to produce crops of better nutritional value.
• Factories for production of recombinant proteins: Recombinant human proteins have been produced using animal and microorganism systems, but due to some shortcomings it has been shifted to the plant system. Vaccines and antibiotics have been obtained from transgenic plants. However, this application is still in the development stage and has not been commercialised yet.

Examples of Transgenic Plants

• Golden rice: Golden rice was produced to overcome the deficiency of vitamin A in children. Using the gene gun methods, rice species were incorporated with the phytoene synthase genes, which increases the vitamin A content of the rice grains.
• Bt cotton: Bt cotton is a genetically modified crop that is resistant to pest bollworm.
• Flavr Savr: Flavr Savr is a genetically modified tomato crop that has a longer shelf life due to delays in ripening and softening.

Several other plants like potato, corn, papaya, maize squash, pumpkin, alfalfa, etc have been modified to obtain crops with better yield and resistance.

Explore BYJU’S Biology to learn more about other Biology-related topics.

Also Read:

• Genetically Modified Crops – An Overview
• What are Bt Crops? – Types, Advantages and Disadvantages
• How are transgenic plants helpful to humans?
• Transgenic Animals – Methods, Examples and Applications