Rapeseed plays an important role in crop rotation:
- Rapeseed increases the following wheat yield. When a rapeseed crop precedes wheat sowing, it allows about 10 % more yield compared to a monoculture of wheat for two consecutive years. Productivity differences can be as high as 30 %.
- A rotation with Rapeseed (Y1) followed by wheat (Y2) is normally cheaper to produce than a wheat- wheat rotation (Y1 & Y2). Weed control costs for wheat are lower after a rapeseed cycle. Fungicide protection costs can also be reduced. Furthermore, the demands for nitrogen (-20 to -50 units) and phosphate fertilization are lower.
- Rapeseed breaks the cereal disease cycle. Eyespot, fusarium and the 'take-all-disease' occur more often in short cereal rotations. The beneficial effects of rapeseed in cereal rotations can only be explained with the "cut-off" effect. In addition, the decomposition of rapeseed crop residues, rich in glucosinolates, leads to the production of toxic compounds that can inhibit fungi stored in the soil.
Compared to cereals, rapeseed usually has different times for sowing, crop management and harvesting. A starter fertilization during sowing in the summer is possible. Additionally, an early nitrogenous fertilization in spring is recommended. Harvesting takes place in summer.
Rapeseed has a high demand of phosphorus, therefore, the application is very important for poor or moderately well-equipped soils and in clayey-limestone soils, where phosphorus may be blocked or is only available in small amounts. In plots with low phosphorus bio-availability, use late summer inputs before crop establishment to limit the risk of early deficiency during fall or apply a starter fertilizer at sowing stage.
The stage of maximum sensitivity to phosphorus deficiency of rapeseed is during the juvenile phase, at the 5-6 leaves stage. Symptoms of Phosphorous deficiencies are growth retardation (dwarf plant) or red leaves (anthocyanins). Phosphorus deficiency leads to a decrease in photosynthesis which is accompanied by the production of anthocyanins (phenolic compounds) which trap free radicals resulting from the dispersion of light energy not used by photosynthesis.
The innovative process of starter fertilization with the fine grade fertilizer EasyStart® ensures an excellent supply of nitrogen and water soluble phosphate to the young plant and due to the direct placement close to the rape seed it ensures a good plant development. Comparatively small amounts of nutrients are used. We recommend an application of 20 kg/ha with EasyStart® for rapeseed. Depending on the operational conditions, a further combination with mineral fertilization (e.g. N or NP, K, S) could be of advantage, especially in the absence of organic fertilization.