Skip to content
agronom.cc cultivar database

Diseases

Scab

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.

Sources10

Breakdown by crop

Apple Scab 1 949 Potato Scab 1 000 Pear Scab 489 Apple Scab 238 Cucumber scab 197 Common Scab of Sugar Beet 34 Plum Scab 10 Peach Scab 9 Olive Leaf Spot 9 Pear Scab 8 Common Scab — Table Beet 8 Apricot Scab 7 Pear scab — Asian pear 7 Citrus Scab 5 Pear Scab — Asian Pear 5 Citrus Scab 3 Pecan Scab 3

Found in these crops

Apple 1 942 Potato 980 European pear 489 Cucumber 266 Apple 236 Sugar beet 33 European plum 10 Peach 9 Pear 8 Garden beet 8 Apricot 7 Japanese pear 7

Varieties that feature this in their description

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.

Kosmač

Active

Malus domestica (Suckow) Borkh. · Apple

SI
2 records

Kolačara

Active

Malus domestica (Suckow) Borkh. · Apple

SI
3 records

Magdalena

Active

Solanum tuberosum L. · Potato

LV
3 records

Konference

Active

Pyrus communis L. · European pear

CZ
4 records

Milada

Active

Solanum tuberosum L. · Potato

CZ
3 records

Londýnské

Active

Malus domestica (Suckow) Borkh. · Apple

CZ
4 records

London Peppen

Active

Malus domestica (Suckow) Borkh. · Apple

SI
2 records

Lionella

Active

Solanum tuberosum L. · Potato

CZ
3 records

Juulikuine

Active

Malus domestica (Suckow) Borkh. · Apple

EE
2 records

Judita

Active

Malus domestica (Suckow) Borkh. · Apple

CZ
8 records

Jucunda

Active

Malus domestica (Suckow) Borkh. · Apple

DE
4 records

Melrouge

Active

Malus domestica (Suckow) Borkh. · Apple

CZ
4 records

Limelight

Active

Malus domestica (Suckow) Borkh. · Apple

NL
2 records

Jump to page 24 48 72 76 96 97 121 145