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.

Darthil

Active

Mahonia aquifolium (Pursh) Nutt. · blue barberry

Miklósné Józsa

2 records

Ajuga reptans L. · Bugle

Tristram Mike|Arundel, West Sussex BN18 0LL, GB

2 records

Veronica longifolia L. · Garden speedwell

Lynne Knosher

2 records

Coreopsis L. · Tickseed

Korlipara Harini

2 records

Cygnet

Active

Tiarella L. · Foamflower

TERRA NOVA NURSERIES INC

2 records

DALON11

Active

Angelonia angustifolia Benth. · Angelonia

Gavriel Danziger

2 records

Echinacea Moench. · Coneflower

Ren Jianping

2 records

Torenia L. · Bluewings

Gavriel Danziger

2 records

BR2012

Active

Euonymus japonicus Thunb. · Japanese spindle

Bart van Roessel

2 records

Erysimum linifolium (Pers.) J. Gay · Wallflower

Trees Scott C

4 records

Barfourteen

Protection expired

Phlox L. · Phlox

Bartels Breeding B.V

2 records

Monarda didyma L. · Bee balm

SCOTT C TREES

2 records

Hibiscus coccineus x Hibiscus moscheutos L.

Zwetzig Gretchen

2 records

Veronica prostrata L.

TERRA NOVA NURSERIES INC

2 records

Rosa L. · Rose

De Ruiter Intellectual Property B.V.

2 records

Aushouse

Active

Rosa L. · Rose

David Austin Roses

3 records

Dahlia Cav. · Dahlia

Han Sasbrink

2 records

Veronica L. · Speedwell

Verschoor Jan|Haarlem, NL

2 records

Triticum aestivum L. · Bread wheat

Nickerson International Research S.N.C.

3 records

Monarda didyma L. · Bee balm

SCOTT C TREES

2 records

Bombay Gold

Terminated

Celosia L. · Cockscomb

VAN DEN BOSCH PIETER CORNELIS

2 records

Lagerstroemia L. · Crape Myrtle

Michael A. Dirr^^^Rhonda Helvick^^^Joshua H. Kardos^^^Oren McBee

2 records

Penstemon Schmidel. · Beard Tongue

Robert D. Jansen

2 records

Jump to page 72 145 194 217 284 289 304 361 394 434