Sugar beet H7-1
The transgenic sugar beet H7-1 (KM-ØØØH71-4) is a development by the German breeding company KWS Saat SE in cooperation with the Monsanto company . It is a sugar beet that is resistant to the total herbicide glyphosate (known under the brand name Roundup ) and was developed to enable the use of glyphosate for weed control in the cultivation of sugar beet.
The effect of glyphosate is based on the blockade of the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in the plants, which leads to a metabolic interruption and thus to the death of the plants. The transgenic form forms an analogous enzyme of the soil bacterium Agrobacterium tumefaciens with the same function, which is not blocked by the herbicide. This makes the sugar beet H7-1 resistant to the pesticide.
Characteristics and genetic modification
Sugar beet H7-1 differs from conventional sugar beet in that it produces an enzyme from a bacterium that differs from the analogue enzyme of the plant and is resistant to the use of the pesticide glyphosate. The starting point for the genetic modification is the 3S0057 sugar beet line, which was supplemented with genetic material from several other species via green genetic engineering .
The genetically modified sugar beet H7-1, like transgenic soybeans and other agricultural plants, contains a gene from the soil bacterium Agrobacterium tumefaciens , strain CP4, which makes it resistant to the active ingredient glyphosate . Glyphosate is a broad-spectrum herbicide that blocks the function of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in all parts of the plant and thus blocks the shikimic acid pathway to the production of certain amino acids and thus inhibits the biosynthesis of the proteinogenic aromatic amino acids phenylalanine , tyrosine and tryptophan . The inserted gene produces a bacterial EPSPS (CP4 EPSPS) that is insensitive to glyphosate.
The Agrobacterium gene was introduced into the plant material as a vector using a plasmid called PV-BVGT08 . The gene for CP4 EPSPS is in this case together with a promoter of the 35 S transcript of a modified figwort mosaic virus ( English figwort mosaic virus , P-FMV) and a E9-3 'terminator sequence of the gene for the small subunit of the ribulose-1 , 5-bisphosphate carboxylase (rbcS) of the pea ( Pisum sativum ) for genetic control and the sequence for a peptide of the EPSPS gene from Arabidopsis thaliana , which transports the C4 EPSPS into the chloroplasts after translation ( English chloroplast transit peptide , ctp2 ), introduced into the plant cells.
The adjacent sequences of the plasmid that are not transferred into the sugar beet also come from Agrobacterium tumefaciens . It is able to reproduce in Agrobacterium tumefaciens as well as in Escherichia coli , and has an aad gene for resistance to spectinomycin and streptomycin and a rop gene to control the number of plasmid copies in the bacteria .
background
In conventional agriculture, the intensive use of herbicides is common in the cultivation of sugar beet in order to prevent the growth of wild herbs in the field. As a rule, four to seven different active ingredients are used here.
Cultivation
In the USA, the herbicide-resistant sugar beet H7-1 was already grown on approx. 475,000 hectares in 2009, the second year after its market launch. The area fell to around 450,000 hectares in 2010, but was again 475,000 hectares in 2011. This corresponds to around 95 percent of the total sugar beet area in the USA. There is also a cultivation in Canada on around 15,000 hectares. In relation to the global cultivation of sugar beet, which amounted to around 4.66 million hectares in 2010, the cultivation area due to cultivation in the USA and Canada is around 10 percent.
The total area for sugar beet cultivation in the USA is around 500,000 ha, somewhat larger than that in Germany (2011: 396,000 ha). The agricultural cultivation of transgenic sugar beet is not permitted in the European Union.
Web links
- Data sheet sugar beet H7-1 in the GM Crop Database at the Center for Environmental Risk Assessment
- Transgen.de - Sugar beet: Less effort in weed control
- Sugar beet database with useful plants profile at transgen.de
Individual evidence
- ^ Center for Environmental Risk Assessment, ILSI Research Foundation: A Review of the Environmental Safety of the CP4 EPSPS Protein. May 26, 2010 ( PDF ( Memento of the original from March 22, 2012 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note. )
- ↑ a b c Data sheet sugar beet H7-1 in the GM Crop Database at the Center for Environmental Risk Assessment, accessed on April 10, 2017.
- ↑ a b http://www.transgen.de/anbau/1180.gentechnisch-veraenderte-zuckerrueben-anbauflaechen-weltweit.html
