A fungal disease of rapeseed caused by the oomycete Hyaloperonospora brassicae, manifesting as chlorotic spots with mycelial growth on cotyledons, leaves, and pods.
In the reference
24
varieties
crop Rapeseed,
where this is mentioned in the description.
The causal agent of the disease is the oomycete Hyaloperonospora brassicae. The disease affects the plant at all stages of vegetation, from emergence to seed maturation. In the early stages, diffuse brownish-green or yellowish spots form on cotyledons and the first leaves, on the underside of which a grey-violet sporulating growth appears under high humidity conditions.
On mature plants, the spots may take on an irregular shape with a dark margin, leading to wilting and premature leaf drop. Infection of pods is also possible. In breeding practice, resistance to the pathogen is evaluated based on the results of field trials, as there is no generally accepted international system for coding races or specific letter designations for resistance genes used for rapeseed varieties.
General information about the subject — on the page
Downy mildew.
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.