Biotechnology Application in Agriculture

Biotechnological Application in Agriculture

  • Biotechnology is a branch of science focused on using genetically modified organisms like microbes, fungi, plants, and animals for large-scale production of biopharmaceuticals and biologicals.  
  • Its applications span various fields, including therapeutics, diagnostics, agriculture, food processing, waste treatment, bioremediation, and energy production. 
  • Three critical research areas in biotechnology are:

- Optimizing Catalysts: This involves improving organisms, typically microbes or enzymes, to serve as efficient catalysts for desired reactions. 

- Engineering Optimal Conditions: Creating the best environment for these catalysts to perform their tasks effectively. 

- Downstream Processing: Developing technologies to purify the desired protein or organic compound produced by the catalyst. 

  • Now, let's see how biotechnology has revolutionized food production and healthcare, enhancing the quality of human life. 
  • Advancements in agricultural technology have revolutionized food production methods, offering innovative solutions to meet the ever-growing demand for food worldwide. In this comprehensive overview, we explore three key approaches to increasing food production: agro-chemical based agriculture, organic agriculture, and genetically engineered crop-based agriculture.

 

Agro-Chemical Based Agriculture:

  • Relies on improved crop varieties, management practices, and agrochemicals like fertilizers and pesticides. 
  • The Green Revolution substantially increased food production by utilizing these methods. 
  • However, agrochemicals can be expensive for farmers in developing countries, limiting their accessibility. 
  • Further increases in yield with existing varieties are challenging using conventional breeding methods.

 

Organic Agriculture:

  • Focuses on natural methods of farming without synthetic inputs like chemical fertilizers and pesticides. 
  • Emphasizes soil health, biodiversity, and ecological balance. 
  • While organic farming promotes sustainability and environmental conservation, it may have lower yields compared to conventional methods.

 

Genetically Engineered Crop-Based Agriculture:

  • Involves genetically modifying crop plants to impart desirable traits such as pest resistance, drought tolerance, or enhanced nutritional content. 
  • Genetic engineering enables precise modification of plant genomes to address specific agricultural challenges. 
  • GM crops have the potential to increase yields, reduce reliance on chemical inputs, and improve crop resilience. 
  • Examples include Bt cotton, Bt corn, and golden rice, which are engineered to resist pests or address nutritional deficiencies.

 

Tissue Culture:

  • Tissue culture is a biotechnological method used for rapid propagation of plants. 
  • It involves growing plant cells or tissues in a controlled environment, allowing for the regeneration of whole plants from explants. 
  • The process exploits the totipotency of plant cells, enabling the production of genetically identical plants (somaclones) in large numbers. 
  • Tissue culture has diverse applications, including micro-propagation for commercial plant production and disease eradication by culturing virus-free meristems.

 

 

 

Somatic Hybridization:

  • Involves fusing protoplasts (isolated plant cells) from different plant varieties to create hybrid protoplasts. 
  • These hybrid protoplasts can be grown to form new plants with combined characteristics of the parent varieties. 
  • Somatic hybrids offer opportunities for introducing novel traits or combining desirable traits from different plant species. 
  • However, the commercial viability of resulting hybrid plants, such as the pomato, depends on the expression of desired characteristics.

 

 

 

Genetically Modified Organisms

  • In the pursuit of sustainable agriculture, farmers seek alternative paths to maximize yields while minimizing reliance on fertilizers and chemicals that harm the environment.  
  • Genetic modification emerges as a promising solution, allowing for the creation of crops tailored to withstand various environmental stresses and reduce the need for chemical inputs.  
  • Genetically Modified Organisms (GMOs), including plants, bacteria, fungi, and animals, have been instrumental in revolutionizing agricultural practices.  
  • This overview explores the multifaceted benefits of genetic modification in agriculture and highlights its potential to address key challenges facing modern farming practices.

 

Enhanced Stress Tolerance:

  • Genetic modification has enabled the development of crops resilient to abiotic stresses such as cold, drought, salt, and heat. These stress-tolerant varieties offer farmers greater flexibility in challenging growing conditions, ultimately leading to increased yields and improved crop resilience.

 

Reduced Reliance on Chemical Pesticides:

  • By introducing genes conferring resistance to pests and diseases, genetically modified crops have reduced the need for chemical pesticides. This bio-control approach minimizes environmental pollution, preserves beneficial insects, and promotes sustainable pest management practices.

 

Decreased Post-Harvest Losses:

  • Genetic modification strategies have led to crops with enhanced shelf life and reduced susceptibility to spoilage, thereby decreasing post-harvest losses. This translates to improved food security, increased marketable yield, and reduced economic losses for farmers.

 

Efficient Mineral Usage:

  • GM crops engineered for improved nutrient uptake and utilization optimize the efficiency of mineral usage, preventing soil degradation and early exhaustion of soil fertility. This sustainable approach promotes long-term soil health and productivity.

 

Nutritional Enhancement:

  • Genetic modification has been employed to enhance the nutritional value of food crops, addressing malnutrition and dietary deficiencies. Notable examples include golden rice, fortified with Vitamin A, which holds the potential to alleviate micronutrient deficiencies in vulnerable populations.

 

Diversified Industrial Applications:

  • Beyond agricultural benefits, genetic modification facilitates the production of tailor-made crops for industrial applications. These include crops engineered to supply alternative resources such as starches, fuels, and pharmaceuticals, contributing to the sustainable utilization of agricultural resources.

 

Biotechnological Applications:

  • Biotechnology plays a pivotal role in agriculture, particularly in the production of pest-resistant plants. The incorporation of the Bt toxin gene from Bacillus thuringiensis into crops has led to the development of bio-pesticides, such as Bt cotton and Bt corn, which offer effective pest control without environmental harm.

 

Bt Cotton

  • Bt cotton is a remarkable example of harnessing biotechnology to combat agricultural pests effectively. Here's a breakdown of how it works:

 

Bacillus thuringiensis (Bt) Toxin Production:

  • Certain strains of Bacillus thuringiensis produce proteins that are toxic to specific insects like lepidopterans (e.g., tobacco budworm, armyworm), coleopterans (e.g., beetles), and dipterans (e.g., flies, mosquitoes). 
  • During a specific growth phase, B. thuringiensis forms protein crystals containing insecticidal proteins.

 

Mode of Action:

  • The Bt toxin exists in the form of inactive protoxins within the crystal. 
  • Upon ingestion by an insect, the alkaline pH of the insect's gut solubilizes the crystals, converting the inactive toxin into an active form. 
  •  The activated toxin binds to the surface of midgut epithelial cells in the insect. 
  • This binding creates pores in the cell membrane, leading to cell swelling, lysis, and ultimately, the death of the insect.

 

Incorporation into Crop Plants:

  • Specific Bt toxin genes are isolated from Bacillus thuringiensis and incorporated into various crop plants, including cotton. 
  •  The choice of toxin genes depends on the targeted pest and the crop being protected. 
  • For example, genes like cryIAc and cryIIAb are effective against cotton bollworms, while cryIAb targets corn borers.

 

Crop Protection:

  • By expressing Bt toxin genes, transgenic crop plants like Bt cotton gain built-in resistance to specific insect pests. 
  • This genetic modification reduces the need for chemical insecticides, promoting environmentally friendly pest control practices. 
  • Bt cotton offers effective protection against targeted pests, leading to increased yields and improved crop quality.

 

 

 

 

 

 

 

Peat Resistant Plants

  • Pest infestations pose significant challenges to agricultural productivity, with nematodes like Meloidogyne incognita causing substantial yield losses in crops like tobacco.  
  • To combat this, a groundbreaking strategy based on RNA interference (RNAi) was employed.  
  • RNAi is a natural cellular defense mechanism present in all eukaryotic organisms, involving the silencing of specific mRNA molecules by complementary dsRNA molecules. Here's how RNAi was utilized to create pest-resistant plants:

 

RNA Interference (RNAi):

  • RNAi is a cellular defense mechanism that silences specific mRNA molecules by complementary dsRNA. 
  • Complementary dsRNA binds to the target mRNA, preventing its translation and effectively silencing gene expression.

 

Application in Pest Control:

  • To combat nematode infestation in tobacco plants, nematode-specific genes were introduced into the host plant using Agrobacterium vectors. 
  • The introduced DNA produced both sense and anti-sense RNA molecules within the host cells. 
  • These complementary RNA molecules formed dsRNA, triggering RNAi and silencing the specific mRNA of the nematode.

 

Mechanism of Action:

  • The dsRNA molecules produced within the transgenic plant initiate RNAi against the nematode. 
  • By silencing specific nematode mRNAs essential for survival, the parasite is unable to thrive in the transgenic host plant.

 

Resultant Protection:

  • The transgenic plant expressing specific interfering RNA becomes resistant to nematode infestation. 
  • This RNAi-mediated defense mechanism effectively protects the plant from nematode damage and reduces yield losses.