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.
Solanum tuberosum L. · Potato
GERMICOPA S.A.S
Solanum tuberosum L. · Potato
Nordkartoffel Zuchtgesellschaft mbH
Solanum tuberosum L. · Potato
Ets Desmazieres Artois Bapume
Solanum tuberosum L. · Potato
STET HOLLAND BV, NL
Solanum tuberosum L. · Potato
John Mara
Solanum tuberosum L. · Potato
Wolfgang Walter
Solanum tuberosum L. · Potato
UNICOPA (FR)/Clause Semences SA (FR)
Malus domestica (Suckow) Borkh. · Apple
Sally Mennell^^^Wilfrid Mennell
Solanum tuberosum L. · Potato
State of Oregon by/through STBHE acting on behalf of Oregon State University
Solanum tuberosum L. · Potato
Saka Pflanzenzucht GmbH Co KG
Solanum tuberosum L. · Potato
Y P VAN DER WERFF
Pyrus x bretschneideri Rehder · Chinese white pear
White Allan
Malus domestica (Suckow) Borkh. · Apple
Markus Kellerhals Agroscope
Cucumis sativus L. · Cucumber
Sin declarar
Solanum tuberosum L. · Potato
M HIGGINS LTD
Solanum tuberosum L. · Potato
STET HOLLAND
Solanum tuberosum L. · Potato
University of Maine System Board of Trustees
Solanum tuberosum L. · Potato
TPC Research BV
Solanum tuberosum L. · Potato
C. Meijer
Beta vulgaris Sugar Beet Group · Sugar beet
KWS, D
Cucumis sativus L. · Cucumber
Nunhems BV (NL)
Solanum tuberosum L. · Potato
SOCIETE CLAUSE
Malus domestica (Suckow) Borkh. · Apple
THOR JOSEF /AGRICULTURAL COOPERATIVE SYCHROV
Beta vulgaris Sugar Beet Group · Sugar beet
KWS, D