Diseases
Leaf spot diseases are a group of fungal, bacterial, or viral disorders manifesting as tissue necrosis in the form of spots of various shapes and colors. Pathogen development leads to a reduction in photosynthetic leaf area, tissue deformation, and significant yield losses.
Mentioned in descriptions 15 926 varieties reference book.
Leaf spot diseases represent a collective group of conditions caused by fungi, bacteria, or viruses. The primary diagnostic symptom is the formation of spots of various colors—brown, yellow, black, or gray—on the leaf blades, ranging from small dots to extensive necrotic lesions with or without margins. Infection often originates in the lower leaf canopy and, if allowed to develop, leads to premature defoliation and overall plant weakening.
Disease progression depends on a combination of favorable meteorological factors, such as moderately warm temperatures and high humidity, as well as the agrotechnical background. Improper crop rotation and the retention of crop residues in fields contribute to the accumulation of inoculum and intensive infection of crops in subsequent seasons. The severity of disease manifestation correlates directly with pathogen aggressiveness and the degree of cultivar susceptibility, which can lead to a 20–30% or greater reduction in crop productivity.
Cultivar resistance to leaf spots is a genetically determined ability to maintain productivity under disease pressure. It can be specific, targeting particular pathogen races, or non-specific polygenic, providing complex protection. Resistance mechanisms include physical barriers, such as waxy coatings, and biochemical responses. During variety testing, resistance is evaluated under natural and artificial inoculation conditions using scoring scales to record the degree of necrosis and pathogen development.
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.
Hordeum vulgare L. · Barley
Dobroudja Agricultural Institute - General Toshevo (BG)
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Royce S Bringhurst et Victor Voth (US)
Solanum lycopersicum L. · Tomato
Ger Bimsdeboer
Helianthus annuus L. · Sunflower
Kovalov Volodymyr Hryhorovych, Zaitsev Oleksii Borysovych,
Solanum lycopersicum L. · Tomato
Harmoniz
Daucus carota L. · Carrot
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Triticum aestivum L. subsp. aestivum · Bread wheat
SEMUNDO| SW Seed GmbH
Brassica oleracea L. (White Cabbage Group) · White cabbage
MARNER GZG| Rijk Zwaan Marne Aktiengesellschaft
Solanum lycopersicum L. · Tomato
Her Bimsdeboer
Hordeum vulgare L. · Barley
Dem"ianenko Alla Ivanivna, Vasylenko Nadiia Vasylivna, Morhun Volodymyr Vasylovych, Shubenko Nadiia Petrivna,
Ribes nigrum L. · Blackcurrant
Instytut Sadownictwa i Kwiaciarstwa im. Szczepana Pieniążka
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Livestock and Seed Division (US)
Solanum lycopersicum L. · Tomato
Teresa Beck Bunn
Beta vulgaris Sugar Beet Group · Sugar beet
MariboHilleshoeg Research AB
Nicotiana tabacum L. · Tobacco
Instytut Uprawy Nawożenia i Gleboznawstwa Państwowy Instytut Badawczy
Oryza sativa L. · Rice
ARS-USDA&ARKANSAS
Zea mays L. subsp. mays (Sweet Corn Group) · Sweet corn
Tovarystvo z obmezhenoiu vidpovidalnistiu "SPARK SIDZ"
Hordeum vulgare L. · Barley
Paul Bury
Prunus avium (L.) L. · Sweet cherry
Matsenko Maksym Oleksandrovych
Solanum lycopersicum L. · Tomato
Hari Besels
Sorghum bicolor (L.) Moench · Sorghum
Prymak Iryna IUriivna, Karanda Tetiana Mykolaivna, Farafonov Viktor Anatoliiovych, Barbaruk Valentyna Tadeushivna, Piter Bohdan Chykaliuk, Larri Richardson,
Cucumis sativus L. · Cucumber
(Ulveczki Gabriella), (Dr.Szarka Janos), (Balogh Peter),
Sorghum bicolor (L.) Moench · Sorghum
Prymak Iryna IUriivna, Karanda Tetiana Mykolaivna, Farafonov Viktor Anatoliiovych, Barbaruk Valentyna Tadeushivna, Piter Bohdan Chykaliuk, Larri Richardson,
Helianthus annuus L. · Sunflower
Seedtec International Inc (US)