Skip to content

Diseases

Powdery mildew

Erysiphales

Powdery mildew is a fungal disease manifesting as a white web-like coating on plant organs, leading to tissue necrosis, fruit deformation, and significant crop losses.

Mentioned in descriptions 33 570 varieties reference book.

Powdery mildew is caused by ectoparasitic fungi of the order Erysiphales, which develop primarily on the surface of leaves, shoots, and fruits. The initial white web-like coating eventually densifies into "powdery" cushions, upon which fungal fruiting bodies may form as dark spots. As a result of the infection, tissues turn yellow and become necrotic, fruits may crack, and leaves drop prematurely.

The intensity of disease development depends on a complex of factors: high relative humidity, moderate temperatures, the presence of dense canopy, and excessive nitrogen nutrition. Risks increase with alternating dry and wet weather. The harmfulness of the disease is expressed in a reduction of the leaf assimilation area, deterioration of crop quality, and a decrease in the general winter hardiness of crops.

Assessment of variety resistance is conducted under field conditions at various stages of vegetation, most often during the full heading phase. To classify the degree of infection, scoring systems or intensity scales in percentages are used, where varieties with up to 10% infection are considered highly resistant (R), 11 to 40% as moderately resistant (M), and more than 41% as susceptible (S). Variety resistance is ensured by genetic mechanisms that prevent colonization by the pathogen or limit the development of its mycelium.

Sources10

Breakdown by crop

Found in these crops

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.

Phlox paniculata L. · Garden phlox

Verschoor Jan|Haarlem, NL

3 records

Pizza

Active

Triticum aestivum L. · Bread wheat

Getreidezüchtung Peter Kunz Peter Kunz

4 records

Panacea

Active

Triticum aestivum L. · Bread wheat

LIMAGRAIN EUROPE

4 records

Rosa L. · Rose

Poulsen Roser A/S

4 records

Rosa L. · Rose

Poulsen Roser A/S

3 records

Rosa L. · Rose

Poulsen Roser A/S

3 records

Lagerstroemia L. · Crape Myrtle

Kardos Joshua H.

3 records

Aster L. · Aster

Oudshoorn Hubertus Gerardus|Rijpwetering, NL

3 records

OLIJDOLO

Active

Rosa L. · Rose

Olij Innovation B.V.

3 records

Mored

Active

Malus domestica (Suckow) Borkh. · Apple

Moors Jozef Jan

6 records

Phlox paniculata L. · Garden phlox

Verschoor Jan|Haarlem, NL

3 records

Mocha

Active

Heuchera L. · Coral Flower

Sandrine Delabroye

3 records

Nijinsky

Terminated

Triticum aestivum L. · Bread wheat

Nickerson International Research S.N.C.

3 records

Monarda didyma L. · Bee balm

Holtmaat Henricus Maria Joseph

3 records

Monarda didyma L. · Bee balm

Walters Gardens Inc

4 records

Spiraea japonica L. f. · Japanese meadowsweet

Pineau Patrick

3 records

Monarda didyma L. · Bee balm

Holtmaat Henricus Maria Joseph

3 records

Rosa L. · Rose

Meilland Alain M.

3 records

Rosa L. · Rose

Meilland Alain A.

4 records

p061105

Active

Fragaria x ananassa Duchesne ex Rozier · Garden strawberry

Vissers America B.V., NL

4 records

Morello

Active

Agastache Clayt. ex Gronov. · Giant hyssop

Janet N. Egger

3 records

Jump to page 72 94 145 184 204 217 289 294 361 434