Bt Crops

Bt Crops’ full form is Bacillus thuringiensis crops. Bt Crops are a class of genetically modified (GM) crops, those that have had their genes taken from the bacteria Bacillus thuringiensis. Bt crops are genetically modified with cry protein from Bacillus thuringiensis, which results in resistance against specific pests. In this article, we will learn about Bt crops, their development, types, advantages and disadvantages, and mode of action in detail.

Definition of Bt Crops

Genes from the Bacillus thuringiensis bacterium have been used to create a type of genetically modified (GM) crops known as Bt crops, or Bacillus thuringiensis crops.

What are Bt Crops?

Genetically modified (GM) Crops known as “Bt crops” are designed to express insecticidal proteins that are derived from the Bacillus thuringiensis (Bt) bacteria. The altered plants have a natural defense system against certain insects, and pests due to these proteins (sometimes referred to as Cry proteins), which are poisonous to certain insect groups. To lessen pest damage, boost crop yields, and reduce the need for chemical pesticides, agribusiness has largely embraced the integration of Bt technology into crops.

Examples of Bt Crops

A protein from the Bacillus thuringiensis (Bt) bacterium is expressed in Bt crops, which are genetically engineered crops designed to withstand specific pests. Examples of Bt crops include the following:

• Bt Cotton
• Bt Maize
• Bt Soyabean
• Bt Eggplant
• Bt Rice
• Bt Potato
• Bt Tomato

The Term Bt

The term “Bt” refers to Bacillus thuringiensis, a naturally occurring soil bacterium that is well-known for creating proteins that are poisonous to several insect pests. For many years, the bacteria has been used as a biological pesticide in organic farming. The production of crystal proteins, or “Cry proteins,” by Bacillus thuringiensis during the sporulation phase is one of its most notable characteristics. Certain insect families, such as caterpillars, beetles, and certain flies, are poisonous to these proteins, but people, animals, and helpful insects are generally thought to be safe among them.

How Bt Crops are Produced?

A procedure known as genetic engineering is used to generate Bt crops, in which target plant genomes are modified to contain certain Bacillus thuringiensis genes. A typical procedure for producing Bt crops looks like this:

1. Identification of Bt genes: The genes of Bacillus thuringiensis that encode for insecticidal proteins more especially, the Cry proteins, are found and isolated by scientists.
2. Gene Cloning: A multiple copy of the chosen Bt genes is produced by cloning in preparation for their eventual transmission.
3. Construction of a Bt Gene Cassette: The Bt genes that have been cloned are integrated into a genetic construct known as a gene cassette. Typically, this construct consists of various regulatory components as well as a promoter region that drives gene expression.
4. Transformation: Through a process known as genetic transformation, the gene cassette is inserted into the genome of the target plant. Various strategies, such as Agrobacterium-mediated transformation or biolistic (gene gun) technologies, can be used to accomplish this.
5. Selection and regeneration: Selectable markers are used to identify plants that have effectively absorbed the Bt genes, and these transformed cells are subsequently regenerated into complete plants.
6. Evaluation: The newly produced Bt plants are subjected to extensive evaluation in controlled field trials to evaluate their performance, including insect resistance and general agronomic qualities.

Different Types of Bt Crops

Bt crops of several varieties have been produced to give resistance to certain insect pests. The insertion of Bacillus thuringiensis (Bt) genes into these crops enables them to manufacture insecticidal proteins, offering an inherent defence mechanism against specific pests. Among the most common varieties of Bt crops are:

• Bt Cotton: Bt cotton is one of the most extensively used Bt crops. It has Bacillus thuringiensis genes that offer resistance to certain lepidopteran pests such as the cotton bollworm and pink bollworm.
• Bt Corn: Bt maize has been genetically engineered to generate poisons that are effective against certain lepidopteran pests such as the European corn borer and the corn earworm. This sort of Bt crop has been widely planted in order to mitigate losses caused by these insect pests.
• Bt Soyabean: In order to give resistance against certain lepidopteran pests, namely the soybean looper, Bt soybeans were created. In soybeans, Bt technology is being introduced with the goal of increasing production while lowering the need for chemical pesticides.
• Bt Eggplant: The genetically engineered Bt brinjal variety is resistant to the aubergine fruit and shoot borer, a significant pest that hinders the development of aubergine in some areas.

Bt Crops in India

India has embraced and grown Bt (Bacillus thuringiensis) crops, mainly Bt cotton and Bt brinjal, as of my most recent information update in January 2022. One of the most extensively grown genetically modified (GM) crops in India is Bt cotton followed by Bt brinjal. Here are some important details regarding Bt cotton in India:

1. Bt Cotton: In India, Bt cotton was first formally introduced in 2002. It has genes from Bacillus thuringiensis, a bacteria that causes a protein that is poisonous to several insect pests, including cotton bollworms.
2. Bt Brinjal: India’s first commercial introduction of a genetically modified plant was the Bt brinjal. But at the moment, the only transgenic crop used for commercial purposes in India is cotton.

Advantages of Bt Crops

Advantages of Bt crops are mentioned below:

• Due to the production of their own insecticidal proteins, Bt crops can lessen the requirement for chemical pesticides.
• Bt crops can withstand harm and production losses from targeted insect pests.
• Farmers may see cost savings from lower pesticide costs as well as possible profits from improved crop yields.
• Because Bt crops have less of an environmental impact than traditional pesticides, their usage can help promote environmental sustainability.
• Bt crops protect a wide variety of beneficial insects by targeting certain pests.
• Bt technology allows for targeted treatment of certain pests without harming unrelated insect species.
• Bt crops give farmers an extra tool for integrated pest management plans, giving them more options for pest control techniques.

Disadvantages of Bt Crops

Disadvantages of Bt Crops are mentioned below:

• Bt crop usage that is extensive and prolonged may cause target pest populations to become resistant.
• There are worries about possible impacts on non-target insects, particularly those that are closely related to the targeted pests.
• Genes from Bt crops can spread to conventional crops or related wild plant species, which might have unforeseen effects or result in the spread of resistant characteristics to natural populations.
• Since Bt crops are only efficient against certain insect groups, they could not offer comprehensive pest management.
• Farmers may find the cost of Bt agricultural seeds prohibitive because of the advanced technology involved.
• Some customers and environmental organisations are worried about the long-term effects and safety of genetically modified organisms, such as Bt crops.
• The efficacy of Bt crops can vary depending on local insect populations and environmental circumstances.

Conclusion – Bt Crops

Bacillus thuringiensis crops, or Bt crops, are a type of genetically modified (GM) crop. Bacillus thuringiensis is the source of their genes. These crops are engineered to generate particular proteins from the bacterium, providing resistance against specific pests. It is important to remember that views regarding the growing of transgenic Bt crops differ by location, and in many of them, official consent is required. In India, Bt cotton is approved and Bt brinjal is under process.

FAQs on Bt Crops

What does Bt mean in Plants?

Bacillus thuringiensis (Bt) crops are genetically modified plants designed to incorporate the (or crystal toxins derived from the Bt bacterium, rendering them resistant to specific insect pests.

Which is the only Bt crop in India?

Bt cotton stands as the sole genetically modified (GM) crop authorized for commercial cultivation in the country.

What is the Advantage of Bt crops?

These crops boost yields, increase farmer profits, reduce soil pollution by requiring fewer pesticides, protect beneficial insects, and offer superior quality compared to conventional crops.

What are Bt crops Examples?

Bt Crops examples are Bt cotton, Bt eggplant, Bt tomato, Bt maize, Bt rice and Bt soybean.

Why is Bt brinjal Banned in India?

Potential harm to small farmers is a concern. Advocates claimed Bt brinjal could cut pesticides and increase yields; critics disputed its environmental and economic effects.

Who Invented Bt crops?

In 1911, Ernst Berliner identified a bacterium that had eradicated a Mediterranean flour moth and later rediscovered it, naming it Bacillus thuringiensis.