Diseases
Scab is a group of crop diseases caused by fungi, actinomycetes, or plasmodiophoromycetes, manifesting as spots, ulcers, and deformations on vegetative and generative plant organs.
Mentioned in descriptions 12 064 varieties reference book.
Apple and pear scab affects leaves, flowers, ovaries, and fruits, manifesting as olive-colored spots with a velvety coating, which leads to fruit cracking and yield loss. In potatoes, several types of scab are distinguished: common scab, where ulcers appear on tubers, and powdery scab, characterized by the formation of warts that rupture into powdery ulcers, as well as root damage.
The development of the disease depends on environmental conditions: for fruit scab, high humidity and rainfall are favorable, while for potatoes, it depends on soil specifics (pH, temperature, and moisture). Varietal resistance is ensured by breeding based on major genes or their combinations. Absolutely immune varieties do not exist, so resistance often manifests as field resistance and depends on the climatic zone.
In variety trials, resistance is assessed visually using a scoring scale or in percentages under natural and artificial infection backgrounds. To increase the accuracy of breeding, molecular genetic marking is used, which allows for the detection of resistance genes by genotype, minimizing phenotypic evaluation errors.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
Cucumis sativus L. · Cucumber
Asgrow (IT)
Malus Mill. · Apple
Murawski, Smadlak, Fisher, M. Fisher
Malus Mill. · Apple
Murawski en Fischer
Malus domestica (Suckow) Borkh. · Apple
Prof. Dr. Manfred Fischer / Heinz Murawski + im Institut für Obstforschung Dresden-Pillnitz / Prof. Dr. Christa Fischer
Cucumis sativus L. · Cucumber
ZAYIN TECHNOLOGY S.L.
Beta vulgaris Sugar Beet Group · Sugar beet
STRUBE HERMANN| Dr. Hermann Strube
Pyrus communis L. · European pear
Malus domestica (Suckow) Borkh. · Apple
Ústav experimentální botaniky AV ČR, v.v.i. (CZ)
Malus domestica (Suckow) Borkh. · Apple
VECHER WILLIAM (US)
Malus domestica (Suckow) Borkh. · Apple
Ústav experimentální botaniky AV ČR, v.v.i. (CZ)
Malus domestica (Suckow) Borkh. · Apple
VANDEPOEL-BEETEN
Solanum tuberosum L. · Potato
Kmetijski inštitut Slovenije (SI)
Malus domestica (Suckow) Borkh. · Apple
N.V.Jo Nicolai en Cie
Pyrus communis L. · European pear
SEMPRA PRAHA A S
Solanum tuberosum L. · Potato
ZPC
Malus domestica (Suckow) Borkh. · Apple
Uniwersytet Przyrodniczy w Poznaniu
Malus domestica (Suckow) Borkh. · Apple
Pepinieres et Roseraies Georges Delbard| FR
Pyrus communis L. · European pear
Station de Geneva (US)
Malus domestica (Suckow) Borkh. · Apple
Pyrus communis L. · European pear
Malus domestica (Suckow) Borkh. · Apple
Pepinieres et Roseraies Georges Delbard| FR
Malus Mill. · Apple
L'INSTITUT NATIONAL DE LA
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Malus Mill. · Apple
L'INSTITUT NATIONAL DE LA