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.
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
"Grupa ""Jagodnik"""
Triticum aestivum L. · Bread wheat
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Phaseolus vulgaris L. · Common bean
PEDRO ALVAREZ, S.L.
Beta vulgaris Sugar Beet Group · Sugar beet
SESVanderhave NV
Capsicum annuum L. · Bell pepper
CAPITAL GENETIC EBT, S.L.
Citrus reticulata Blanco · Mandarin orange
VARIOS OBTENTORES
Hordeum vulgare L. · Barley
SEJET PLANTEFORÆDLING
Prunus cerasus L. · Sour cherry
Turovtsev Mykola Ivanovych, Turovtseva Valentyna Oleksandrivna,
Beta vulgaris Sugar Beet Group · Sugar beet
SAS Florimond Desprez Veuve & Fils
Zea mays L. subsp. mays (Popcorn Group) · Popcorn
CROOKHAM COMPANY
Cucumis sativus L. · Cucumber
Kees Reinink
Cucumis sativus L. · Cucumber
Kees Reinink
Brassica oleracea L. (White Cabbage Group) · White cabbage
Monakhos Hryhorii Fedorovych
Erysimum linifolium (Pers.) J. Gay · Wallflower
A T Yates & Son
Fragaria L. · Strawberry
Kopan Volodymyr Pavlovych, Kopan` Kira Mykolaivna,
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Fresh Forward Holding B.V.
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE & CO.KGAA
Zea mays L. subsp. mays (Maize Group) · Maize
Dekalb Genetics Corporation (usa) (US)
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE & CO.KGAA
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE & CO.KGAA
Salvia L. · Sage
Hans A. Hansen
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE & CO.KGAA
Zea mays L. subsp. mays (Maize Group) · Maize
PANNAR UK LTD.
Echinacea purpurea (L.) Moench · Purple coneflower
Kees van den Aardwegh