Applications of Biotechnology in agriculture

Introduction

Biotechnology is the application of science in the preparation and usage of many organic or biological products such as food and drugs. Biotechnology in conjunction with genetics play a vital role both in small scale and the large scale production of organic compounds. With the advent of genetic science and biotechnology, a lot of industrial production of biopharmaceuticals has seen an ever-increasing uptrend. By using the principles of genetics and advanced biotechnology, many genetically modified microbes have been prepared. Artificial production of useful species of fungi, plants and animals have been the boon for the entire world. A range of medical therapies, (therapeutics) disease diagnostic tools, cell and tissue cultures in a laboratory setting have been successfully used since the last 3 decades. In the field of agriculture, it helped to produce many disease resistant and genetically modified crops that sustain against the most vulnerable environmental conditions. Food processing is another area where the principles and practices of biotechnology are successfully used. This article is designed to further explore the plethora of applications of biotechnology in various fields.

Table Of Contents

1. Introduction

2. Biotechnology and agriculture- green biotechnology

3. An insight into crop modification techniques

   3.1 Traditional crossbreeding

   3.2 Mutagenesis

   3.3 Polyploidy

   3.4 Genome editing

   3.5 Protoplast fusion

   3.6 RNA interference

   3.7 Transgenic process

4. Role of biotechnology in developing disease-resistant breeds

5. Role of biotechnology in producing insect and pest-resistant plants

6. Developing herbicide tolerance by using Biotechnology

7.Delayed fruit ripening and biotechnology

 

Biotechnology and agriculture- green biotechnology

The world is witnessing a chronic state of hunger due to food crisis. This is because of poor and outdated farming techniques that primarily rely on the excess use of pesticides, weedicides and artificial composts. Biotechnology has helped many farmers to practice organic and chemical-free agricultural technology.  However, the large-scale agriculture supported by biotechnology is still poor. Biotechnology and its applications in the field of agriculture is a great way to manage environmental pollution, global warming due to green gas effects, and depletion of the groundwater tables. Many agricultural organizations have been successfully promoting the techniques of biotechnology in improving yields. Biotechnology has made crop production easy, quick and also made it possible with a limited water source. Genetically modified crops have resulted in producing disease-resistant, safe, fast-growing and high-yielding plant and animal population. Agricultural biotechnology is simply known as green biotechnology. Three of the most significant uses of biotechnology are; agrochemical based agriculture, organic agriculture and genetically engineered crop-based agriculture. The primary intention of the agricultural biotechnology is to prepare GMOs (genetically modified organisms). GMOs has the ability to resist against illnesses and are also highly productive.  GMOs are the result of modification of genetic material found in the bacteria, fungi and animals. The advantages of GMOs are:

 

  1. The resulting breeds have a fast turnaround, for instance, if the expected time of harvesting the final crops is 3 months, GMOs have brought them down to 2 months or even lesser to make the harvesting process quicker thereby allowing the farmers to use the land again. This has saved time, money, effort and resources.

  2. Genetically modified foods have gained a longer shelf-life hence, they can be packed and transported to distant places without allowing them to spoil.

  3. The resulting crops became highly tolerant to abiotic stressors such as excessive cold, drought, salt and the environmental heat.

  4. Crops became less reliant or dependent on chemical sprays.

  5. Green biotechnology has also helped to reduce the post-harvest losses.

  6. Plants made by GMO based technology has increased the mineral usage thereby resulting in high soil fertility.

  7. The nutritional value of foods has improved a lot without adding additives, for example, a papaya fruit had better levels of vitamin-A.

  8. The combined application of biotechnology and genetics has helped to introduce many new breeds that are a combination of 2 or more pure breeds.

 

However, there are a few risks that have been identified by scientists. The drawbacks of biotechnology-based products are:

  1. On the long run, GM crops have started developing antibiotic resistance that made the farmers difficult to treat some illnesses.

  2. Farmers growing genetically modified foods had to face a lot of legal liability by governing bodies and in many cases, it was being misused for growing crops that are not legally approved. 

  3. Some of the GM foods had to be subjected to serious laboratory assay before their final approval to release into open markets.

  4. In some cases, application of biotechnology turned into an expensive affair making it impossible to afford by the small scale farmers.

  5. Since some alterations are made at the molecular level, purity of breeds is still in question. 

  6. Some genetically modified foods may present the risk of cancer. 

 

An insight into crop modification techniques

Traditional crossbreeding

It is the most conventional technique used for centuries. The crossbreeding is done between the 2 sexually compatible species that create a desired variety of offspring. While selecting mates, breeders chose them based on what they need in their future progeny. For instance, a specific type of seed colour, seedless fruit crops, tall plants and strong pods and colourful flowers.

 

Mutagenesis

As we know that mutation can be useful in the long run as it helps to achieve desirable variation in the species across generations, however uncontrolled mutation is not a good sign for farmers. Mutagenesis is a technique where mutations are randomly induced in the plant population. It is done by using chemicals and radioactive substances that give rise to a desirable variation. Although it is not advisable to consume such plant products but not all the progenies are harmful.

 

Polyploidy

It is used to increase the number of chromosomes in a crop where the resulting progeny will be either larger in size or the number of fruits or nuts per plant is increased. For example, seedless watermelons are created in this manner by taking a 4-sets of chromosome from the watermelon and crossing them with a 2-set chromosome of another watermelon. The resulting progeny will give rise to a sterile (seedless) watermelon with 3 sets of chromosomes.

 

Genome editing

Genome editing has been a very popular and scientifically proven technique since the 1980s. It is the application of an enzyme system that modifies the DNA directly within the cell. Genome editing creates herbicide-resistant plants that can control weeds.

 

Protoplast fusion

Protoplast fusion is a method where cells and cellular components of 2 different species are mixed. For instance, by using protoplast fusion, the radish with male sterility trait can be crossed with red cabbages. The resulting progeny is a mixed variety of progeny with better features.

 

RNA interference

It experimented where genes are suppressed. It is a process in which cell’s RNA is manipulated so that protein synthesis can be turned off. This results in the gene suppression of the progeny.

 

Transgenic process

It is the procedure through which a piece of DNA is inserted into another organism's DNA to create a new variety with a desired set of trait`s in the future progeny. It is a straight forward method used by most of the biotechnologists.

 

Role of biotechnology in developing disease-resistant breeds

Because of the environmental stressors, plants and animals are becoming more and more vulnerable to diseases. The advent of green biotechnology has made things better by introducing the hybrid verities that can resist pests fungal, viral and bacterial infections. One such example is the Bt toxin produced by a bacterium called Bacillus thuringiensis. The gene of Bt toxin has been cloned from the strain of bacteria and made it to express in plants. This has allowed the plants to develop resistance against insects so that there is no need to use harmful insecticides. Some of the examples of Bt breeds are Bt corn, Bt cotton, rice, tomato, potato and soya bean. The strains of Bacillus thuringiensis can produce certain proteins which have the ability to kill certain insects such as tobacco budworm and armyworm.

 

Role of biotechnology in producing insect and pest-resistant plants

For a plant to gain resistance against pests and insects, RNA interface( RNAi) technique is used. This technique works on the suppression of protein synthesis.  By using a complementary DOUBLE STRANDED RNA (dsRNA) molecule that binds and prevents translation of the mRNA, the suppression of protein synthesis is being done. In other words, it involves silencing of a specific mRNA by introducing a complementary RNA in the form of an infection by viruses having RNA genomes or mobile genetic elements (transposons) that replicate via an RNA intermediate.  One of the experimental example is that, by using Agrobacterium vectors, some specific genes were introduced into the host plant, which in turn produced both sense and anti-sense RNA in the host cells. The combination of these 2 strands has given rise to a double-stranded (dsRNA) that initiated RNAi to produce specific mRNA of the nematode.

 

Developing herbicide tolerance by using Biotechnology

Herbicides are frequently used to control weeds which will eventually spoil the fertility of the soil and also the quality of yield.  Herbicides generally kill only a narrow spectrum of plants sometimes including the desired crops if the spray is stronger enough. Biotechnologists soon realized that if a crop plant is genetically engineered to be resistant against a broad-spectrum herbicide, problems of weeds can be easily mitigated by using a simplified and safer chemicals at a limited dose. In the past, resistance to synthetic herbicides has been successfully done into corn, soybeans, cotton, canola, sugar beets, rice, and flax.

 

Delayed fruit ripening and biotechnology

There are several techniques applied to delay the ripening fruit process. A genetic modification in the resulting progenies has helped to achieve this. The most common techniques are Suppression of ACC synthase gene expression (aminocyclopropane), Insertion of the ACC deaminase gene, insertion of the SAM hydrolase gene, suppression of ACC oxidase gene expression etc. These techniques can assure the crops that yield quality fruits and vegetables, easy transportation, waste reduction by early decaying, reduction in postharvest losses, and extension of their shelf life.



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