Transgenic plants : Transgenic plants Presented by Subhasmita Pattnaik contents: contents Introduction Methods of producing transgenic plants Applications Strategies of Transgenic plants Transgenic plants in India Benefits Conclusion Introduction: Introduction Transgenic plants are the results of modern biotechnology. An organism containing a transgene introduced by technological (not breeding) methods is called transgenic. Transgenes are the genetically engineered gene added to a species. The process of producing transgenic organism is called transgenesis . PLANT TRANSFORMATION METHODS: PLANT TRANSFORMATION METHODS Transfer of DNA via a vector: Agrobacterium Direct transfer of DNA: gene guns electroporation microinjection Agrobacterium mediated method: Agrobacterium mediated method Agrobacterium -mediated transformation is most commonly used method for transgenesis . A.tumefaciens is a rod shaped Gram negative soil bacterium found in the rhizosphere . It contains Ti plasmid(tumor-inducing) which causes crown gall disease in dicot plants. It mainly infect the wound site and causes disease symptoms. PowerPoint Presentation: Ti plasmid:- Ori T-DNA regions Vir region A region enabling conjugative transfer genes for catabolism of opines Gene gun method: Gene gun method The method was first used by Klein et al.(1987) to transform epidermal cell of Allium cepa . This method is mainly used for cereals transformation. Good for plants that cannot be transformed by Agrobacterium , e.g. most monocot DNA is bound to tiny particles of gold or tungsten which are subsequently shot into plant tissue or single plant cells under high pressure.The particles penetrate both the cellwall and membranes. Electroporation: Electroporation In this technique,short pulses of high voltage are applied to protoplasts which make temporary pores in the plasma membrane to increase their permeability and facilitate the uptake of foreign gene. Microinjection method: Microinjection method Microinjection involves direct physical approach in depositing DNA into specific target cells. The protoplasts are immobilised in agarose or on glass slides coated with polylysine or by holding them under suction by a micropipette. The exogenous DNA of interest is taken in microinjector and then directly delivered inside the cell. Micromanipulator is used for microinjection of the DNA. A maximum of 40-50 protoplasts can be microinjected in one hour. Successful transformation by microinjection of cells has been achieved in tobacco , alfalfa etc. PowerPoint Presentation: Applications Insect resistant cotton – Bt toxin kills the cotton boll worm transgene = Bt gene from Bacillus thuringiensis Insect resistant corn – Bt toxin kills the European corn borer. transgene = Bt protein PowerPoint Presentation: Herbicide resistant crops - soybean , corn, canola transgene = EPSP synthase Virus resistance papaya - resistant to papaya ring spot virus transgene = virus coat protein Prolonged storage time: Prolonged storage time Transgenic tomato with delayed ripping:lower level of ethylene production Reduced activity of the cell wall degrading enzymes, e.g. polygalacturonases Antisense molecules: Antisense molecules The Golden Rice Fact : The Golden Rice Fact Rice, the principal crop of India is extremely low in vitamin A. This deficiency can lead to blindness,diarhae,malaria and tuberculosis. It was contributed by two German research team headed by Potrykus and Peter Beyer . Rice endosperm synthesize geranyl-geranyl pyrophosphate which can be converted into ß-carotene by 3 enzymes. Phytoene desaturase and Lycopene ß Cyclase derived from daffodil( Narcisssus pseudonarcissus ) and Carotene desaturase from Erwinia uredova . The transgenes providing these enzyme activities were transferred into rice Agrobacterium mediated transformation. The resulting rice looks yellowish orange in colour and contain ß-carotene kwnon as ‘Golden Rice’. Strategies of transgenic plants: Strategies of transgenic plants The People’s Republic of China was the first country to allow commercialized transgenic plants, introducing a virus-resistant tobacco in 1992. The first genetically modified crop approved for sale in the U.S., in 1994, was the FlavrSavr tomato , which had a longer shelf life. In the US, by 2009-10, 93% of the planted area of soybeans, 93% of cotton, 86% of corn and 95% of the sugar beet were genetically modified varieties. A total of 29 countries worldwide grew transgenic crops in 2011 by approximately 16.7 million farmers and 50% of transgenic crops grown worldwide were grown in developing countries. Transgenic plants in India: Transgenic plants in India India cultivated its first transgenic Bt cotton crop, which was developed in the private sector, on 0.05 million hectares in the year 2002. In 2009, transgenic Bt cotton was cultivated by 5.6 million farmers on 8.6 million hectares. India now occupies second position in terms of global cotton production by turning out 35 million bales of cotton in 2010. Benefits: Benefits More economically friendly as pesticides do not go into the air, soil, and water .Their production hazards to the environment also decreases. Reduction of sicknesses and illnesses, as transgenic crops are more nutritious. Vitamins and minerals can be provided to children and to people, where they were inaccessible before. The most obvious benefit is yield increase.It could potentially solve hunger. We can begin to grow foods in different conditions. Other foods that grow in cold climates could be engineered to grow in hot climates Enhancement of the taste and quality of food. CONCLUSION: CONCLUSION Transgenic plants have the potential to solve many of the world's hunger and malnutrition problems, and to help protect and preserve the environment by increasing yield and reducing reliance upon chemical pesticides and herbicides.