A genetically modified soybean has DNA introduced into it using genetic engineering techniques. In 1996 the first genetically modified soybean was introduced to the U.S. market, by Monsanto. In 2014, 90.7 million hectares of GM soy were planted worldwide, 82% of the total soy cultivation area.
Reason for GM Soybean
Glyphosate is a broad spectrum nonselective herbicide which kills all dicotyledonous plants when sprayed . So, when this is sprayed in soybean field weeds along with crop plant get killed. So, in order to make the crop plants resistant to the herbicide Monsanto developed Roundup Ready , a genetically modified soybean. A variety GTS-40-3-2 variety is glyphosate resistant soybean
Mode of action
Glyphosate acts by interfering with the synthesis of essential aminoacids like phenylalanine, tyrosine and tryptophan. EPSP enzyme (Enolpyruvylshikimate-3-phosphate synthase) absent in animals and therefore animals must consume it to obtain aromatic aminoacids as they are unable to synthesize it.
Construction of Plasmid and insertion
A plasmid containing 35S promoter from CaMV(cauliflower mosaic virus), chloroplast transit peptide (CTP4) coding sequence from Petunia hybrida and terminational element from A.tumefaciens was inserted in soybean germplasm through genegun method of transformation. Roundup ready expresses a kind of EPSPS from the strain of A.tumefaciens which protects the soybean from killing action of glyphosate. Later it was patented on first generation of Roundup Ready soybean expired in March 2015.
Commercialisation to market
Monsanto developed glyphosate-resistant soybean also expresses Cry1Ac protein from Bacillus thuriengiensis and the glyphosate-resistance gene.
First commercially approved in United States(19994) and many countries like Canada(1995), Japan and Argentina (1996), Uruguay, Mexico, Brazil, South Africa and United nations approved subsequently.
Later many varieties have been developed by crossing original variety of Roundup Ready. Dupont released varieties for GM soybean oil also.