Applications of Biotechnology in Agriculture

The Green Revolution tripled the global food supply using improved crop varieties and agrochemicals (fertilisers and pesticides). However, it is no longer sufficient to feed the growing population, and excessive chemical use causes environmental pollution. Biotechnology provides a sustainable alternative through tissue culture and Genetically Modified (GM) crops.

• Agrochemical-based agriculture: Traditional farming relying heavily on chemical fertilisers and pesticides.
• Organic agriculture: Eco-friendly farming using biofertilisers and biopesticides.
• Genetically engineered crop-based agriculture: Utilising biotechnology to create crops with optimised traits.

When traditional breeding fails to meet demand, tissue culture allows for rapid, large-scale plant multiplication. Explants (any part of a plant) are grown in sterile test tubes using special nutrient media containing sucrose, inorganic salts, vitamins, and growth regulators (auxins, cytokinins).

• Totipotency: The inherent capacity of a single plant cell or explant to generate a complete, whole plant.
• Micropropagation: The technique of producing thousands of plants in a very short duration using tissue culture.
• Somaclones: The plants produced via micropropagation are genetically identical to the original parent plant (widely used for commercial tomatoes, bananas, and apples).
• Disease-Free Recovery: Even if a plant is infected with a virus, its apical and axillary meristems remain virus-free. Culturing these meristems allows for the recovery of completely healthy plants from diseased ones.
• Recalcitrant Seed Solution: Ideal for preserving plants with recalcitrant seeds (seeds that die if their moisture drops below certain levels or if frozen).

This is the process of fusing isolated naked protoplasts (plant cells whose cell walls have been digested, leaving only the plasma membrane) from two different plant varieties to combine their desirable characteristics.

• Somatic Hybrids: The resulting hybrid plants.
• Example: Pomato is a somatic hybrid created by fusing tomato and potato protoplasts. (Note: It did not possess the right combination of traits for commercial viability).

GMOs are plants, bacteria, fungi, or animals whose genetic material has been precisely altered by inserting targeted transgenes.

• The Catalyst: Providing the most effective biological catalyst, usually in the form of a genetically modified microbe or a pure enzyme.
• The Environment: Engineering the optimal conditions required for that catalyst to function efficiently.
• The Extraction: Developing downstream processing technologies to properly purify the resulting protein or organic compound.

• While the Green Revolution significantly increased food production using agrochemicals, biotechnology offers a sustainable alternative to overcome yield limitations and chemical pollution.
• Tissue culture enables micropropagation, allowing for the rapid, large-scale production of genetically identical and disease-free plants from small tissue samples.
• Somatic hybridisation allows scientists to fuse the cell-wall-free protoplasts of two distinct plant varieties to create new hybrids with combined desirable traits.
• Genetically modified crops are engineered to possess highly beneficial characteristics, including enhanced nutritional value and increased tolerance to harsh environmental stresses.
• Agricultural biotechnology drastically reduces the reliance on harmful chemical pesticides by developing inherently pest-resistant plants, such as Bt cotton.