Genetically modified crops

Speaker:- Parichay S.R

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• DNA of GM organisms have been altered through genetic engineering and inserted into desired plant.

• Genetic modification involves- introduction, integration, and expression of foreign genes into host plants.

• Modified by taking a gene from another cell type and adapting it into the GM organism DNA.

• It was first described in Tobacco by Agrobacterium mediated vector in 1970.

Introduction:-

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• There are two main aspects that can be improved by genetic modification:– Alteration of input traits:

• Resistance to pests and harmful factors• Resistance to pesticide, herbicide• Resistance to disease and virus

– Alteration of output traits:• Increased output of crops• Increased duration of shelf life• Increased nutritional value• Increased health benefits• Medical benefits

Characterstics

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Some Genetically modified crops:-

#) Bt Brinjal (Bacillus thuringiensis)

#) Golden Rice

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Bt Brinjal

• created by inserting a crystal protein gene (Cry1Ac) from the soil bacterium Bacillus thuringiensis into the genome of brinjal species.

•accomplished using Agrobacterium-mediated genetic transformation.

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How it is Effective against pests????

•When fruit and shoot borer larvae feed on Bt brinjal plants, they ingest the Bt protein Cry1Ac along with plant tissue.

•In the insect gut, which is alkaline with a pH >9.5, the protein is solubilized and activated by gut proteases.

• The Bt protein binds to specific receptor proteins present in the insect membrane, resulting in pore formation in the membranes.

•This leads to disruption of digestive processes, paralysis, and subsequent death of the fruit and shoot borer larvae.

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Golden Rice

•It is a variety of Oryza sativa rice produced through genetic engineering to biosynthesize beta-carotene.

• It was engineered to overcome the deficiency of Vitamin A

•Golden rice was created by transforming rice with two beta-carotene biosynthesis genes:1) psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus)2) crtI from the soil bacterium Erwinia uredovora

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A simplified pathway of carotenoid synthesis in Golden Rice

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Benefits:-

•GM crops can be modified to be resistant to pests as well as pesticides and herbicides.

•GM crops can also be made to resist disease and other drastic environmental conditions.

•GM crops are mostly altered for extra nutritional value for more health benefits.

•This leads to a higher income when selling crops for commercial farmers.

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Controversies:-

• The possibility that genes might spread from modified crops to wild relatives might pose health risks to consumers.

•The development of GM products which have been found to cause allergic reactions in many ways.

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Thank You

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