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 vesca L. · Wild strawberry
Instytut Sadownictwa i Kwiaciarstwa im. Szczepana Pieniążka
Solanum lycopersicum L. · Tomato
Robert Priieur
Festuca trachyphylla (Hack.) Hack. · Hard fescue
BARENBRUG HOLLAND| Barenbrug Holland B.V. (Variety Administration)
Lactuca sativa L. · Lettuce
Bejo Zaden B.V.
Ribes nigrum L. · Blackcurrant
Gospodarstwo Ogrodnicze Wiesław Błocki
Beta vulgaris Garden Beet Group · Garden beet
Wielkopolska Hodowla Roślin Ogrodniczych
Solanum lycopersicum L. · Tomato
Panchev IUrii Ivanovych
Brassica napus var. napus · Rapeseed
Hodowla Roslin Smolice Sp.z o.o Grupa IHAR
Beta vulgaris Sugar Beet Group · Sugar beet
Khart Rodzher Evelin
Lupinus angustifolius L. · Narrow-leaf lupin
Poznanska Hodowla Roslin Sp. z o.o
Beta vulgaris Sugar Beet Group · Sugar beet
Betaseed
Beta vulgaris Sugar Beet Group · Sugar beet
Betaseed
Triticum aestivum L. · Bread wheat
Hodowla Roslin Smolice Sp.z o.o Grupa IHAR
Allium cepa L. var. cepa · Onion
Kibbutz Beit Alpha
Beta vulgaris Sugar Beet Group · Sugar beet
SESVANDERHAVE NV-SA, BE
Beta vulgaris Sugar Beet Group · Sugar beet
DLF Beet Seed APS
Fragaria L. · Strawberry
Kopan Volodymyr Pavlovych, Kopan` Vira Mykolaivna,
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Solanum lycopersicum L. · Tomato
Ferry Morse Seed Co.(USA) (US)
Capsicum annuum L. · Bell pepper
William McCarty
Beta vulgaris Sugar Beet Group · Sugar beet
VANDERHAVE SUGAR BEET B.V
Triticum aestivum L. · Bread wheat
Florimond Desprez SA (FR)/INCONNU (FR)
Cucumis sativus L. · Cucumber
Bayer Holland B.V.
Solanum lycopersicum L. · Tomato
Yonat Partok