The complex ability of winter rapeseed to withstand adverse overwintering conditions, including frosts, thaws, and temperature fluctuations. It determines crop survival and the necessity for spring reseeding.
In the reference
81
varieties
crop Rapeseed,
where this is mentioned in the description.
To assess the winter hardiness of rapeseed, a visual inspection of the root system is conducted; a healthy root should remain white without brown spots. In field conditions, a critical plant density threshold is considered to be 10 plants per square meter, below which crops must be reseeded, while the optimal density is 25–50 plants per square meter.
Rapeseed is capable of withstanding frosts down to –15…–20 °C without snow cover and down to –30…–35 °C with it. The optimal state for overwintering is considered to be a plant in the rosette phase with 6–8 leaves, a root collar diameter of 8–10 mm, and a growing point located at or below the soil surface.
The risk of crop failure increases when plants become overgrown, as the growing point is elevated above the soil surface, making them vulnerable to temperatures below –8…–10 °C. To increase resistance, hardening at temperatures near freezing is necessary, which promotes the accumulation of soluble substances in the cells.
General information about the subject — on the page
Winter hardiness.
Varieties of Rapeseed mentioned in the description
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.