After sowing, young sugar beet plants develop very slowly. Wild grasses and weeds usually grow quicker and compete against the crop for light, water and nutrients. Farmers must start very early with weed control – shortly before or shortly after the beets emerge. Usually several applications of chemical plant protection (herbicides) are called for. Mechanical control is also possible, but it is expensive and labour-intensive.
Without weed management, the yield of cultivated sugar beets would be reduced by around 75 %, depending on the number of weeds present.
The development of herbicide-tolerant sugar beets began in the mid-1990s. The aim was to be able to fight weeds in sugar beet cultivations in an easy, effective and environmentally-friendly way.
The sugar beet H7-1, which can be seen in the Üplingen Plant Science Garden, is resistant to the active substance or herbicide glyphosate. This broad-spectrum herbicide blocks a certain protein common in the green parts of all plants, meaning plant growth is hindered and the plant dies soon after. However, there is a new sugar beet that does not react in such a way when herbicides containing glyphosate are applied. It contains a gene stemming from a soil bacterium which "neutralises" the effect of the herbicide.
This genetically modified sugar beet opens up new possibilities for effective weed control that allow for more flexibility in timing of application. Fewer herbicides are also needed than in conventional cultivation. Because of that, farmers save time on labour and machine costs which means less energy consumed and a lower carbon footprint. Additionally, cultivation of the soil can be reduced thus preventing soil erosion. It is also expected that it will be easier in future to apply the 'threshold of damage' principle, i.e. spraying only when the amount of weeds exceeds a certain number. This can have an overall positive effect on biodiversity in the field during vegetation.
Glyphosate can then be applied also in sugar beet cultivations when herbicide-tolerant varieties are present. This active agent has been approved and safely used in Germany since 1975.
The herbicide-tolerant sugar beet H7-1 is grown in the Plant Science Garden. It is treated twice with the glyphosate herbicide.
In the neighbouring plots:
Zum Vergleich stehen auf den Nachbarparzellen:
Up until the time of harvest, visitors to the Plant Science Garden can observe how the sugar beets – and the weeds – develop on the different plots.
Date: 2011
Young sugar beets can hardly compete with weeds. In the Plant Science Garden a new method is being tested so that farmers can better deal with this problem.
Sugar beet is grown worldwide on 4.6 million hectares. The main areas of cultivation are in the EU (33.9%), Russia (21.5%) and the USA (10.7%). Sugar beet area in the entire EU totals 1.56 million hectares with Germany (23.5%) and France (23.7%) being the top countries of cultivation. Around 21% of the world's sugar production is derived from sugar beets.
In Germany cultivation area has increased once again. In 2011, more than 33,000 farmers are planting 396,000 hectares of sugar beets.
Herbicide-tolerant sugar beets were first grown in the USA in 2007. Three years later they were pretty much the norm, being grown on an area of 470,000 hectares, equivalent to more than 95% of the sugar production in the USA. This far surpasses the total cultivation of sugar beets in Germany. In 2011 again, herbicide-tolerant sugar beets will account for around 95% of the area cultivated in the USA. This is an indication of their wide acceptance among American farmers.
For political reasons, the cultivation of herbicide-tolerant sugar beets cannot be expected in Europe before 2015. Up to now, their commercial cultivation has not been approved in the EU. However, their use as food and feed has been approved in the EU since 2007. Thus the import of sugar or feed derived from genetically modified sugar beets is possible.
Sugar is a highly refined product that does not differ materially whether produced from conventional or genetically modified sugar beets. Even so, sugar derived from GM sugar beets must be so labelled in the EU.
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