What is Roundup Ready seed? What vegetables are gene spliced with Roundup?

Expert response from Dr. L. Curtis Hannah

Professor, University of Florida

Friday, 11/12/2015 13:02

Thank you for your question. Roundup Ready refers to plants genetically engineered to be resistant to the herbicide Roundup. The active ingredient in this herbicide is a chemical called glyphosate. This chemical blocks the production of an essential component needed for plant life and consequently the plant dies after treatment with this herbicide.  

More specifically glyphosate inhibits an enzyme called 5-enolpyruvylshikimate 3-phosphate synthase, sometimes abbreviated EPSPS. This enzyme is needed for the synthesis of a particular class of amino acids. Scientists inserted a form of the enzyme isolated from a bacterium that is resistant to glyphosate and, in turn, made plants resistant to this herbicide. Note that the enzyme is exactly like the one found in plants in terms of what it does. The engineered form simply can do “its thing” in the presence of the herbicide. Most likely the plant form and the bacterial form trace back through evolution to the same gene. 

Very few engineered vegetables are on the market. Two reasons account for this. First, the amount of money seed companies make from the sale of vegetable seeds does not normally justify the present-day huge cost needed for government approval of engineered vegetables. Second, the anti-science, anti-GMO propaganda machine unnecessarily interferes with public acceptance of engineered fruits and vegetables. Sweet corn perhaps is an exception since genes approved for field corn can be used in sweet corn. The cost of “deregulation” then has been paid for field corn use. There are some engineered sweet corns on the market, including Roundup Ready.