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Biotechnological Applications in Agriculture and Medicine:
1. Biotechnology essentially deals with industrial scale production of biopharmaceuticals
and biologicals. The applications of biotechnology include therapeutics, diagnostics,
genetically modified crops for agriculture, processed food, bioremediation, waste treatment
and energy production.
2. Biotechnology have the following three critical research areas:
(i) To provide the best catalyst in the form of improved organism, usually a microbe or pure
enzyme.
(ii) To create optimal conditions through engineering for a catalyst to act.
(iii) Downstream processing technologies to purify the protein/organic compound.
3. Biotechnological Applications in Agriculture
(i) Biotechnology applications in agriculture involve following three options:
(a) Agrochemical based agriculture.
(b) Organic agriculture.
(c) Genetically engineered crop-based agriculture.
(ii) Green revolution increased food production due to the use of:
(a) Improved crop varieties.
(b) Agrochemicals (fertilisers and pesticides).
(c) Better management practices.
(iii) Genetically Modified Organisms (GMOs) are plants, animals, bacteria and fungi whose
genes have been altered by manipulation.
(iv) Genetic modification in plants have lead to following:
(a) Crops became more tolerant to abiotic stresses, such as cold, drought, salt, heat, etc.
(b) Dependence on chemical pesticides reduced, i.e. pest resistant crops.
(c) Post harvest losses reduced.
(d) Efficiency of mineral usage increased in plants (preventing loss of soil fertility).
(e) Nutritional value of food is enhanced, e.g. vitamin-A enriched rice.
(f) Tailor made plants are created by using GM plants to supply alternative resources to
industries, in the form of starches, fuels and pharmaceuticals.
(v) Some of the applications of biotechnology in agriculture are the production of pest
resistant plants, which decrease the amount of pesticide used.
Bt toxin is produced by a bacterium and expressed in plants to provide resistance to insects,
in effect created a biopesticide, e.g. Bt cotton, Bt corn, golden rice, tomato, potato and
soybean, etc.
(a) Bt cotton is created by using some strains of a bacterium, Bacillus thuringiensis (Bt is
short form,).
(b) This bacterium produces proteins that kill certain insects such as lepidopterans
(tobacco, budworm and armyworm), coleopterans (beetles) and dipterans (flies and
mosquitoes).
(c) B. thuringiensis forms protein crystals during a particular phase of their growth. These
crystals contain a toxic insecticidal protein.
(d) Bt toxin protein exist as inactive protoxins, but once an insect ingests the inactive toxin, it
is converted into an active form of toxin due to the alkaline pH of the gut, which solublise the
crystals.
(e) The activated toxin binds to the surface of midgut epithelial cells and create pores that
cause cell swelling and lysis leading to death of an insect.