Plant Biotechnology: Revolutionizing Agriculture

1. Chapter 6 Plant Biotechnology

2. Agriculture: The Next Revolution • Biggest industry in the world ($1.3 trillion of products per year) • Plant transgenesis allows innovations that are impossible to achieve with conventional hybridization methods • Resistant to herbicides • Pest resistant • Vaccines

3. Methods Used in Plant Transgenesis • Unique advantages of plants: • The long history of plant breeding provides plant geneticists with a wealth of strains that can be exploited at the molecular level • Plants produce large numbers of progeny; so rare mutations and recombinations can be found more easily • Plants have been regenerative capabilities, even from one cell • Species boundaries and sexual compatibility are no longer an issue

4. Methods Used in Plant Transgenesis • Selective Breeding • Farmers cross plants with desirable traits to increase the likelihood of producing offspring with that trait. selective breeding animation

5. Methods Used in Plant Transgenesis • Protoplast Fusion to create plant hybrids • Degrade cell wall with cellulase • A cell lacking a cell wall is called a protoplast • The protoplasts from different species of plants can be fused together to create a hybrid • The fused protoplasts grow in nutrient agar for a few weeks • The colonies are then transferred to media to induce root and shoot growth

6. Methods Used in Plant Transgenesis • Selective Breeding vs. Biotechnology Traditional selective breeding vs. biotechnology

7. Methods Used in Plant Transgenesis • Transgene – gene for a desirable trait introduced into a novel organism • Transgene construct contains a promoter, terminator, and selectable marker gene

8. Methods Used in Plant Transgenesis • Transformation by Agrobacterium Method • Ti plasmid integrates into the DNA of the host cell, making it an ideal vehicle for transferring recombinant DNA to plant cells Animation: Gene Transfer in Plants Using Ti Plasmid

9. Methods Used in Plant Transgenesis • Leaf Fragment Technique • Small discs of leaf incubated with genetically modified Agrobacterium Ti plasmid • Treat with hormones to stimulate shoot and root development Animation: Engineer a Crop

10. Methods Used in Plant Transgenesis • Transformation by Gene Gun Method • Blast tiny metal beads coated with DNA into an embryonic plant cell Gene Gun animation

11. Methods Used in Plant Transgenesis • Chloroplast Engineering • More genes can be inserted at one time • Genes are more likely to be expressed • DNA is separate from the nucleus

12. Methods Used in Plant Transgenesis • Plant Breeding and Testing Overview of crop genetic engineering

13. Methods Used in Plant Transgenesis • Antisense Technology • Flavr SavrTM tomato introduced in 1994 • Ripe tomatoes normally produce the enzyme, polyglacturonase (PG) which digests pectin • Scientists isolated the PG gene, produced a complementary gene which produces a complementary mRNA that binds to the normal mRNA inactivating the normal mRNA for this enzyme Antisense technology

14. Methods Used in Plant Transgenesis • RNA Interference (RNAi) • Inhibits gene expression by interfering with transcription or translation of RNA molecules Protein expression silenced by RNAi Active protein expression RNAi video and animations

15. Practical Applications in the Field • Disease Resistance • Vaccines for plants contain dead or weakened strains of plant viruses to turn on the plant’s immune system • Transgenic plants express viral proteins to confer immunity

16. Practical Applications in the Field • Insect Control • Bacillus thuringiensis (Bt) produces a protein that is toxic to plant pests • Transgenic plants contain the gene for the Bt toxin and have a built-in defense against these plant pests Animation: How Bt Affects Insects

17. Practical Applications in the Field • Weed Management • Herbicide resistance Weed-infested soybean plot Transgenic soybean plot after Roundup treatment

18. Practical Applications in the Field • Safe Storage • avidin-blocks the availability of biotin for insects • Stronger fibers • Increase strength of cotton fiber by 60%

19. Practical Applications in the Field • Enhanced Nutrition • Golden rice that is genetically modified to produce large amounts of beta carotene • QPM: Maize with increased nutritive value QPM program in Haiti

20. Practical Applications in the Field • Future Transgenic Products • RNAi to generate caffeine free coffee beans. • Biotech Crop Database Animation: Future GMOs

21. Practical Applications in the Field • The Future: From Pharmaceuticals to Fuel • Plant-based petroleum for fuels • Biofuel – fuel derived from biomass

22. Types of Biofuels • Bioethanol – alcohol made by fermenting plant based sugar compounds Video tour of an Ethanol Plant

23. Types of Biofuels • Biodiesel-vegetable oil or animal fat derived diesel fuel Comparison of biodiesel output for different feed stocks

24. Biofuel Production • Generation 1 Biofuels: Food Sources

25. Biofuel Production Corn Used for Ethanol production 1985-2008

26. Biofuel Production • Biotechnology Solutions for Generation 1 • The soybean

27. Biofuel Production • Generation 2 Biofuels: Non-Food Sources

28. Biofuel Production • Biotechnology Solutions for Generation 2 • GM Jatropha doubles oil yield

29. Practical Applications in the Field • Metabolic Engineering • Manipulation of plant biochemistry to produce nonprotein products or to alter cellular properties

30. Health and Environmental Concerns • Human Health • Allergens • Antibiotic resistance

31. Health and Environmental Concerns • Environmental Impact • Effect on non-target species • Super weeds

32. Health and Environmental Concerns • Regulations • US Department of Agriculture (USDA) • Safe to grow • Food and Drug Administration (FDA) • Safe to consume • Environmental Protection Agency (EPA) • Poses little or no environmental risk

33. Plant Biotechnology