Transgenic crops are genetically modified crops containing genes artificially transferred from an unrelated species. The first GM crop was produced in 1982. GM crops can be engineered for resistance to biotic stresses like insects and diseases using genes like Bt toxin, or for abiotic stresses like drought and salinity. Golden rice was developed for improved nutrition containing beta-carotene. While GM crops promise increased yields and nutrition, concerns exist regarding allergens, effects on biodiversity, and business issues relating to seed patents. With proper safety testing and regulation, transgenic crops could help address world hunger and environmental issues.

1. TRANSGENIC CROPS
SEMINAR PRESENTATION
BY
MIKA GHOSH
B.SC BIOTECHNOLOGY
UG SEM II

2. WHAT ARE TRANSGENIC CROPS ?
 A transgenic crop is a Genetically modified crops.
 Transgene means genetically modified genes.
 Transgenic indicates that a transfer of genes has occurred using recombinant
DNA technology.
 Generally a transgenic crop contains one or more genes that have been
inserted artificially either from an unrelated plant or from different species
altogether by different genetic engineering processes.

3. HISTORY
 Was under trial and error for almost 9900 years.
 The first genetically modified crop was produced in 1982, using an
antibiotic resistant tobacco plant.
 In 1992 the president of China introduced a virus resistant tobacco
plant.
 The first genetically modified plants approved for sale in U.S in
1994 was the Flavr Savr tomato which has longer self life, as it
took longer to soften after ripening.
 Around 1996 35 approvals had been granted commercially to
grow 8 transgenic crops and one flower crop with 8 different trait
 In 2000 vitamin A rich Golden rice was produced.

4. AN OVERVIEW OF THE PROCESS

5. How to make
Transgenic Crops ?
In plants cells insertion of foreign DNA is called Transformation.
The transformation is of two types :
 Hereditary
 Non hereditary
For the incorporation of foreign gene following methods used
 Indirect
 Direct

6. TRANSFORMATION
INDIRECT
 Agrobacterium mediated gene
transfer
A. Tumefaciens
A. rhizogenes
 Virus mediated
DIRECT
 Micro injection
 Biolistics
 Electroporation
Etc...

7. Types Of Transgenic Crops
 Transgenic Crops for resistance to biotic stresses.
 Transgenic Crops for resistance against abiotic stresses.
 Transgenic Crops for increased productivity and nutritional quality.
 Transgenic Crops for floriculture or ornamentals.

8. Resistance to biotic stresses
Trans gene is incorporated so to develop resistance against herbicides, insect,
viruses, bacteria and fungal pathogens..
 Herbicides normally affect processes like photosynthesis and biosynthesis of
essential amino acids.
 In case either the target protein is made insensitive to herbicides or a
pathway is introduce that will detoxify them.
 Example – Soybean, Corn, Canola etc.
 Insect resistance plants are also developed by genetic engineering either using
Bt gene or secondary metabolites.
 Similarly viral,bacterial and fungal pathogens resistance plants are also
developed using respective trans genes.

9. Bt Toxin
 Bt stands for Bacillus thuringienesis (gram +ve soil bacterium).
 Some strain of BT kill certain insects due to an insecticidal protein produced
by them, which disrupts the digestive tract function of the insects.
 But doesn’t harm mammals and itself gets degraded within 20sec in
mammalian digestive tract.
 Bt toxin is coded by a gene named cry that are of different classes active
against specific insects
 Ex-Bt cotton (cryIAc & cryIIAb act against cotton bollworms),Bt corn(cryIAb
act against corn borer) etc..

10. Resistance to abiotic sources
 Trans gene is incorporated so to develop resistance against draught, high and
low temperature, salinity, osmotic stress etc in plants.
 For this purpose transgenes are isolated from wild plants, algae,ferns,
bryophytes and some angiosperms that withstands these abiotic stresses.
 Proline-5- Carboxylate synthase gene is used for draught resistance.
 Trehalose 6 phosphate synthase is used to develop resistance to heat,cold
and osmotic stresses as the product of this gene Trehalose is a non
reducing disaccharide which accumulates at such conditions.
 High levels of thermo tolerance have been achieved by using heat shock
proteins or by alternating levels of osmolytes that maintain membrane
fluidity.

11. Productivity and nutritional quality
 Transgene is incorporated for the development of enhancement to
productivity and nutritional quality of crop yield.
Approaches for increased crop productivity by Trangenes
 Improved harvest index
 Higher Biomass production
 Hybrid seed production
Approaches for improved nutritional quality by transgenes
 By improvement of functional food and neutraceuticals
 Manipulation of grain quality in cereals
 Super food bio fortified for micronutrients
 Improved oil composition in oil crops

12. Golden Rice
 Golden rice is a genetically modified rice that contains large amount of vitamin A.
 The rice contains the element beta carotene which is converted to vitamin A inside
human body.
 Beta carotene is needed by humans to make vitamin A which is essential for good vision.
 Transgene used:
 psy(phytoene synthase)
 crtI(carotene desaturase)

13. Floriculture or ornamentals
Transgene is incorporated to development of production of
transgenics with novel aesthetic properties of ornamental
crops.
For Transgenic ornamentals approaches follows:
 Plants size and flower yield
 Flower colours
 Flower and inflorescence architecture
using mutant gene
 Flowers with longer self life
 Improved flower fragnance

14. Advantages of GM crops
 improved nutritional quality
 increased crop yield
 insect resistance
 disease resistance
 herbicide resistance
 salt tolerance
 biopharmaceuticals
 saving valuable top soil
 ability to grow in harsh environment

15. Disadvantages of GM crops
 Allergic reactions
 Production of toxins
 Reduced nutritional value
 Release of toxins to soil
 Resistance of pests to toxins
 Disruption of biodiversity

16.  Unacceptable intervention in “God’s Creation”
violating barriers in natural world
 Objections in consuming animal genes in plants and
vice versa.
 Business controversies
 Patenting GM seeds creates trouble for farmers as
they have to buy it every year with greater cost.
Etc....

17. Conclusion
 Transgenic crops have potential to solve world’s hunger and malnutrition
problems
 It has potential to help protect and preserve the environment by increasing
yielded and reducing reliance upon chemical pesticides and insecticides.
 Safety testing and regulation can ensure it’s superiority.
 The society can be enlightened with the scientific Technology.