Salvador
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 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.
Horix
TerminatedLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Saratoga
TerminatedLactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
NL
4 records
Cimano
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Felicie
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Golem
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Kountry
TerminatedLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Lapeza
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
SV2538LA
TerminatedLactuca sativa L. · Lettuce
Bayer Holland B.V.
NL
3 records
Planet
ActiveLactuca sativa L. · Lettuce
BLUMEN GROUP S.P.A
IT
2 records
Kildary
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Gomer
ActiveLactuca sativa L. · Lettuce
RAMIRO ARNEDO, S.A.
ES
2 records
Marcellus
TerminatedLactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
NL
3 records
Marzial
TerminatedLactuca sativa L. · Lettuce
Syngenta Crop Protection AG
NL
4 records
Parinice
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
3 records
SV5362LA
TerminatedLactuca sativa L. · Lettuce
Seminis Vegetable Seeds
NL
3 records
Socca
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Bridenice
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Alpera
ActiveLactuca sativa L. · Lettuce
Enza Zaden Beheer B.V.
NL
4 records
Ruboise
ActiveLactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
FR
2 records
Lagatta
TerminatedLactuca sativa L. · Lettuce
Nunhems B.V.
NL
4 records
Myamar
ActiveLactuca sativa L. · Lettuce
Vilmorin-Mikado S.A.S.
FR
3 records
Vanguard 75
ActiveLactuca sativa L. · Lettuce
DR. E.J. RYDER
Tarantela
ActiveLactuca sativa L. · Lettuce
Vilmorin-Mikado SAS (FR)
FR
3 records