Mosslanding
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
3 records
Diseases
Downy mildew of lettuce
Lactuca sativa L.
A fungal disease of lettuce caused by the obligate oomycete Bremia lactucae, characterized by high pathogen variability and the appearance of chlorotic angular spots with sporulation on the underside of leaves.
In the reference 2 007 varieties crop Lettuce, where this is mentioned in the description.
The disease is caused by the oomycete Bremia lactucae Regel, which exhibits high genetic variability. Pathogen populations include numerous physiological races, designated by the code Bl followed by a sequence number, the composition of which is constantly changing, making it difficult to maintain cultivar resistance.
Symptoms appear as chlorotic angular spots on the upper side of the leaf, restricted by veins. On the underside, a characteristic loose whitish, gray, or violet sporulation layer forms. Affected tissues become necrotic, leading to leaf desiccation and stunted seedling growth.
Breeding for resistance is based on the use of Dm-genes (Downy mildew) and quantitative trait loci (QTL). Cultivar resistance is determined by the ability to withstand specific races of the pathogen; however, the effectiveness of protection is limited due to the ability of local Bremia lactucae populations to overcome genetic resistance.
General information about the subject — on the page Downy mildew.
Varieties of Lettuce 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.
Babila
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Lunaverde
ActiveLactuca sativa L. · Lettuce
MARALDI SEMENTI S.r.l.
IT
2 records
Kealia
ActiveLactuca sativa L. · Lettuce
Vilmorin-Mikado SAS (FR)
FR
2 records
Kaskaro
TerminatedLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Parabole
ActiveLactuca sativa L. · Lettuce
Syngenta Crop Protection AG
NL
4 records
Sycamore
WithdrawnLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
3 records
Procurio
ActiveLactuca sativa L. · Lettuce
Syngenta Seeds B.V.
NL
3 records
Quice
ActiveLactuca sativa L. · Lettuce
Vilmorin-Mikado SAS (FR)
FR
3 records
Celanie
ActiveLactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel BV (NL)
FR
3 records
Fiansaï
ActiveLactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel BV (NL)
FR
3 records
Or Anton
ActiveLactuca sativa L. · Lettuce
ORTORICERCA SRL
IT
2 records
Burgandy
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
Moonice
ActiveLactuca sativa L. · Lettuce
Syngenta Crop Protection AG
NL
4 records
Brenniga
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Gorio
TerminatedLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
WINTER DENSITY
ActiveLactuca sativa L. · Lettuce
SEMINIS VEGETABLE SEED IB
ES
2 records
Xoana
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Ricote
TerminatedLactuca sativa L. · Lettuce
RAMIRO ARNEDO, S.A.
ES
2 records
Estelena
ActiveLactuca sativa L. · Lettuce
Syngenta Crop Protection AG
NL
4 records
Ice Metal
Application submittedLactuca sativa L. · Lettuce
Syngenta Crop Protection AG
NL
3 records
Marinie
ActiveLactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel BV (NL)
FR
4 records
Amboise
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Cospenza
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records