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.
Pyrus pyrifolia (Burm. f.) Nakai · Japanese pear
Pyrus pyrifolia (Burm. f.) Nakai · Japanese pear
Malus domestica (Suckow) Borkh. · Apple
Solanum tuberosum L. · Potato
Pyrus communis L. · European pear
Solanum tuberosum L. · Potato
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Malus domestica (Suckow) Borkh. · Apple
Beta vulgaris Sugar Beet Group · Sugar beet
Werner Beyer Monica Weber Maik Gertz Dietrich Hauer
Cucumis sativus L. · Cucumber
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Solanum tuberosum L. · Potato
SIPRE
Solanum tuberosum L. · Potato
CAITHNESS POTATO BREEDERS LTD
Malus Mill. · Apple
Murawski en Fischer
Malus Mill. · Apple
Fischer, M. / Fischer, C. / Murawski, H.