Diseases
Allium cepa L. var. aggregatum G. Don
A fungal disease of shallots caused by the oomycete Peronospora destructor, manifesting as diffuse stunted growth or localized necrotic spots with a grayish-purple bloom.
In the reference 8 varieties crop Shallot, where this is mentioned in the description.
The causal agent of downy mildew on shallots is the oomycete Peronospora destructor. The disease occurs in two forms: diffuse, characterized by early yellowing and curling of leaves when infected through planting material, and local, in which chlorotic spots develop on leaves followed by sporulation during wet weather.
In breeding for resistance to the pathogen, genes from wild Allium species are used, particularly the dominant gene Pd1 derived from Allium roylei. Despite the development of specialized hybrids such as Innovator, most shallot varieties do not possess complete immune resistance to this disease.
General information about the subject — on the page Downy mildew.
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.
Allium cepa L. var. aggregatum G. Don · Shallot
Union des Coopératives Agricoles
Allium cepa L. var. aggregatum G. Don · Shallot
ALLIUM SEEDS UK LTD
Allium cepa L. var. aggregatum G. Don · Shallot
SCEA Glidic Arnaud (FR)
Allium cepa L. var. aggregatum G. Don · Shallot
Agri-Obtentions S.A., Institut National de Recherche pour l'Agriculture l'Alimentation et l'Environnement (INRAE)
Allium cepa L. var. aggregatum G. Don · Shallot
Union des Coopératives Agricoles
Allium cepa L. var. aggregatum G. Don · Shallot
Allium cepa L. var. aggregatum G. Don · Shallot
Allium cepa L. var. aggregatum G. Don · Shallot