Sugar beet
The queen of crops, that's what the sugar beet is also called. Being "sweet", however, is not the only feature. The development of its use played a major part in the agro-industrial revolution of the past, more than 200 years ago. Now, the sugar beet is back in the game when it comes to new technologies involving the use of sugar molecules: as energy storage, in bioreactors, or in building materials for anything the 3D printer can create.
The sugar beet has the highest nutrient requirements
With this perspective for the future, the crop is still an important crop rotation element in the important arable regions of Germany. Within the crop rotation, sugar beet places the highest demands on the supply of macro- and micronutrients.
- Potassium is a prerequisite for high, reliable yields, and is important for optimum nitrogen efficiency.
- Magnesium maintains the assimilation performance of the leaves and the build-up of important plant constituents.
- High sugar yields are achieved through balanced nutrient supply.
- Heavy losses are likely in the event of boron deficiency.
The sugar beet is a supplier of valuable sugar and bioenergy
Sugar beet is primarily cultivated for sugar production. There are also other developments in the bioenergy sector, such as ethanol, biogas and bioplastics, which may provide potential for new uses of sugar beet in the future. Sustainable production of the high-quality raw material sugar beet requires sophisticated cultivation technology and the economically and ecologically optimal use of operating resources.
The most important nutrients for sugar beet
Potassium – the prerequisite for high sugar beet yields
- With a potassium uptake of 450-600kg/ha K2O, potassium is the most important nutrient in sugar beet cultivation in terms of quantity.
- The larger amounts of potassium are found in the physiologically active green leaf mass, while the potassium content in the storage organ, the beet, is significantly lower.
- Potassium is known for its positive effects on yield formation and sugar content.
- Potassium promotes photosynthetic performance, which leads to increased formation of substances in carbohydrate metabolism (sucrose formation).
- Furthermore, it favors the discharge of assimilates and their incorporation into the beet body.
- Potassium strengthens the plant against diseases, therefore maintaining its efficiency.
- Insufficient potassium levels in the soil jeopardize soil fertility and have a negative impact on yield and sugar content.
Potassium for improved quality in sugar beet
- The most important quality factor of sugar beet is its sugar content.
- Due to its specific physiological effects, potassium has a positive influence on sugar formation, derivation, and storage.
- In trials, an increase in sugar content of 0.5-1.0% polarization could be measured through optimal potassium fertilization (payout price per tonne of beet increases).
- Potassium and sodium (Na) influence the alkalinity of the raw sugar juice. A minimum alkalinity of the raw juice is necessary for sugar production.
- In some regions, a quality premium is additionally determined by the standard molasses loss (SMV). In terms of fertilization, the standard molasses loss is mainly determined by the α-amino nitrogen content.
- Following the introduction of the quality calculation formula for calculating sugar yield, potassium fertilization has hardly any influence on standard molasses loss, since slightly increasing potassium contents in the beets are overcompensated by decreasing α-amino nitrogen contents. The standard molasses loss therefore remains largely unchanged.
- Optimum potassium supply improves the nitrogen efficiency of the sugar beet.
High sugar yield through balanced nutrition
Magnesium
Magnesium has a particularly positive effect on yield, firstly because it maintains the assimilation performance of the beet leaves for a long time and secondly because it regulates the citric acid cycle during cell respiration and therefore the build-up of important plant constituents (proteins, fats, carbohydrates).
Sulfur
Good sulfur supply favors sugar quality by reducing α-amino nitrogen content. Sulfur deficiency increases the standard molasses loss.
Furthermore, sulfur has the following functions:
Sulfur activates important enzymes in energy and fatty acid metabolism. It is essential for the synthesis of sulfur-containing amino acids, influences overall protein synthesis and thus has a positive effect on yield.
An optimal sulfur supply leads to efficient nitrogen utilization. After all, if there is a lack of sulfur, the nitrogen taken up cannot be converted into proteins and a signal is sent to the roots to take up less nitrogen. Therefore, the plant's need for sulfur must be met for optimal nitrogen utilization.
Sulfur enables sugar beet to maintain its physiological processes optimally even under drought stress and avoid or at least minimize yield losses. Sulfur is a component of the metabolic product glutathione, which, as an antioxidant, renders oxygen radicals formed during drought stress harmless and thus prevents necrosis of the leaves.
Sodium
Sufficient sodium supply improves water utilization and can partially offset potassium deficiencies during dry periods. Trial results indicate yield increases of 300-600kg/ha sugar by sodium applications of 20-40 kg/ha.
Boron
Boron is important for cell tissue formation and the production of ingredients (e.g. sugar). Boron deficiency leads to heart rot and dry rot and consequently to considerable yield losses.
Manganese
Manganese has similar metabolic functions to magnesium. It has a positive influence on yield, e.g. through improved assimilation of the beet leaves during vegetation.
Fertilization recommendations for sugar beet
The aim of fertilisation is to maintain soil fertility in order to make full use of the natural yield potential in the long term. To achieve this, an optimum nutrient content must be maintained in the soil (soil nutrient status class “C” in Germany), i.e. nutrients removed with the harvested crop must be replaced through fertilisation. In addition to nutrient removal, allowances must be made for site-specific losses (for example through leaching) and to compensate for previous deficits.
Recommendation for soil fertilization
The nutrients to be applied should be supplied in chloride form, as sugar beet is a chloride-loving crop. The best time for potassium fertilisation is shortly before sowing.
The following fertilisation recommendations are calculated based on the nutrient removal by the main harvested product and assume optimum soil nutrient levels (soil nutrient status class “C” in Germany). Allowances for site-specific losses through leaching, fixation or erosion are not included.
- 500-800 kg Korn-KALI per ha at a high yield level; 400-600 kg/ha at a medium yield level.
- In the case of boron deficiency, 500-800 kg/ha Korn-KALI+B; 400-600 kg/ha at a medium yield level.
- 200-300 kg/ha ESTA Kieserit to meet magnesium and sulphur requirements.
Product recommendation
Recommendation for foliar fertilization
Foliar fertilisation effectively supplies the plant with the micronutrients boron, manganese, zinc or copper.
It also specifically complements soil fertilisation with readily available macronutrients such as magnesium or sulphur. During periods of vigorous growth, foliar fertilisation meets peak nutrient demand and reliably ensures optimum nutrient supply even under dry conditions or when sulphur mineralisation is too slow.
This ensures optimum yields and quality. If deficiency symptoms have already occurred, foliar fertilisation provides effective and rapid relief.
Product recommendations
To meet peak demand and correct latent magnesium and sulphur deficiency, 20-30 kg/ha epsoTOP is recommended. In cases of severe deficiency or visible deficiency symptoms, the application rate can be increased to up to 45 kg/ha, split into two to three applications.
epsoBORTOP can be applied from row closure to additionally meet the boron requirements of sugar beet. Several applications of 5-10 kg/ha each can be made.
