Introduction

Definition: Biotechnology is the application of scientific and engineering principles to the processing of materials by biological agents to provide goods and services. — OECD (1982)

Agricultural Biotechnology: It is the application of biotechnology tools and techniques to modify plants, animals, and microorganisms for agricultural production and processing.

Branches of biotechnology

Major areas of agricultural biotechnology

• Plant Tissue Culture
• Genetic Engineering
• Molecular Markers and Genomics
• Transgenic Crops (GM crops)
• Biofertilizers and Biopesticides
• Micropropagation
• Molecular Diagnostics and Marker-Assisted Selection
• Bioinformatics

Plant tissue culture

Definition: The in-vitro (under sterile conditions) culture of plant cells, tissues, or organs on a nutrient medium under controlled environment.

Father of Plant Tissue Culture: Haberlandt (1902)

Key Concepts:

• Totipotency: Ability of a single cell to develop into a complete plant.
• Callus: Unorganized mass of cells formed in culture.
• Somatic Embryogenesis: Development of embryos from somatic cells.
• Organogenesis: Formation of organs (shoots, roots) from callus.

Applications:

• Rapid clonal propagation (micropropagation)
• Virus elimination
• Production of secondary metabolites
• Germplasm conservation
• Somaclonal variation for crop improvement

Important Media:

• MS Medium (Murashige and Skoog, 1962) – Most commonly used.
• B5 Medium (Gamborg, 1968) – For legume cell culture.

Genetic engineering

Definition: The direct manipulation of an organism’s DNA to introduce new traits.

Steps of Genetic Engineering:

• Isolation of DNA
• Gene cloning using vectors
• Gene insertion into host organism
• Selection and screening
• Expression of desired gene

Important Tools:

Fact:

• First restriction enzyme discovered by Hamilton Smith (1970).
• Recombinant DNA technology developed by Stanley Cohen and Herbert Boyer (1973).

Transgenic crops (gm crops)

Definition: Crops that contain genes artificially inserted from another organism (via recombinant DNA technology).

Objectives:

• Pest and disease resistance
• Herbicide tolerance
• Improved yield and quality
• Stress tolerance (drought, salinity)
• Nutritional enhancement

Important Examples:

Fact:

• First GM crop: Flavr Savr Tomato (1994, USA)
• First GM crop in India: Bt Cotton (2002, Mahyco-Monsanto)
• Bt gene: Cry1Ac