WHAT ARE TRANSGENIC PLANTS?• Modification of DNA using genetic engineering techniques.• Aim is to introduce a new trait to the plant .• The inserted sequence is known as the transgene.• The purpose of inserting a combination of genes in a plant, so as to

make it as useful and productive as possible. • Examples in food crops include resistance to certain pests,

diseases, or environmental conditions, reduction of spoilage, or resistance to chemical treatments (e.g. resistance to a herbicide), or improving the nutrient profile of the crop.

• Examples in non-food crops include production of pharmaceutical agents, biofuels, and other industrially useful goods, as well as for bioremediation.

WHY MAKE TRANSGENIC PLANTS?

• Desirable genes may provide features such as higher yield or improved quality, pest or disease resistance, or tolerance to heat, cold and drought.

• Transgenic technology enables plant breeders to bring together in one plant useful genes from a wide range of living sources.

• Generate more useful and productive crop varieties containing new combinations of genes.

• Expands the possibilities beyond the limitations imposed by traditional cross-pollination and selection techniques.

HISTORY• The first genetically modified crop plant was produced in 1982, an

antibiotic-resistant tobacco plant.

• In 1987, Plant Genetic Systems ,founded by Marc Van Montagu and Jeff Schell, was the first company to genetically engineer insect-resistant (tobacco) plants by incorporating genes that produced insecticidal proteins from Bacillus thuringiensis (Bt).

• The first genetically modified crop approved for sale in the U.S, in 1994, was the FlavrSavr tomato as it had a longer shelf life.

• In 1994, the European Union approved tobacco engineered to be resistant to the herbicide bromoxynil, making it the first commercially genetically engineered crop marketed in Europe.

HISTORY

• In 1995, Bt Potato was approved by the US Environmental Protection Agency, making it the country's first pesticide producing crop.

• In 1995 canola with modified oil composition (Calgene), (Calgene), Bt cotton (Monsanto), glyphosate-resistant soybeans (Monsanto), virus-resistant squash (Asgrow), and additional delayed ripening tomatoes (DNAP, Zeneca/Peto, and Monsanto) were approved.

• In 2000, Vitamin A-enriched golden rice, was the first food with increased nutrient value.

MOST COMMONLY USED GENETIC ENGINEERING TECHNIQUES

• Microprojectiles (biolistics or particle gun) for gene transfer

• Agrobacterium tumefaciens mediated transformation

• Electroporation • Microinjection

TRANSGENIC PLANTS FOR CROP IMPROVEMENT

• NutritionSome GM soybeans offer improved oil profiles for processing or healthier eating. Camelina sativa has been modified to produce plants that accumulate high levels of oils similar to fish oils.• Vitamin enrichment Golden rice, developed by the International Rice Research Institute (IRRI), provides greater amounts of Vitamin A targeted at reducing Vitamin A deficiency.• Toxin reductionA genetically modified cassava under development offers lower cyanogen glucosides and enhanced protein and other nutrients (called Bio Cassava).• Stress resistanceIn 2011, Monsanto's Drought Gard maize became the first drought-resistant GM crop to receive US marketing approval.

• Herbicides(i) Glyphosate-The transgenic petunia plants resistant to

glyphosate(active ingredient of Roundup herbicide) were developed by transfer of a gene for EPSPS(5-enol-pyruvyl-shikimat-3-phosphate synthase), that overproduces this enzyme.

(ii) Bromoxynil-Tobacco plants have been engineered to be resistant to the herbicide bromoxynil.

(iii) 2-4D- The transgenic maize and soyabean resistant to 2-4D were developed by inserting a bacterial aryloxyalkanoate dioxygenase gene, aad1 makes the corn resistant to 2,4D.

• Pest resistance(i) Insects-The Bt toxin produced by Bacillus thuringiensis has

been isolated and used for Agrobacterium Ti plasmid mediated transformation of tobacco, cotton and tomato plants.

(ii) Virus- 80% of Hawaiian papaya plants were genetically modified by incorporating Pseudorabies virus (PRV) DNA.

ADVANTAGES• For the producers of the new varieties- A high efficiency in plants is obtained. • For farmers-Process of pests destroying is simplified, therefore less damage.-Production output is increasing as well as the profits of transgenic cultures, even the obtaining cost of the GMO is rather high.• For industry- As in the case of modified starch, low lignin content wood (in this case paper manufacturing is less pollutant), human protein production(for therapeutic aim)• For consumers- More nutritious-Fruits and vegetables with delayed maturation can easily be stored, with minimum losses.-In future, transgenic plants contain higher content of vitamins, minerals, essential amino acids by using the vaccine plants, the rice enriched in pro-vitamin A etc.• For the environment and human future-Imply lower pollution-Higher agricultural productions

GLOBAL STATUS OF BIOTECH CROPS IN YEAR 2014