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.
Festuca arundinacea Schreb. · Tall fescue
Timothy M. Ford, Pineview Farms, LLC
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Livestock and Seed Division (US)
Triticum aestivum L. · Bread wheat
SECOBRA RECHERCHES S.A.S
Malus domestica (Suckow) Borkh. · Apple
SERIDA
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Information not available - Contact NL authorities
Poa pratensis L. · Kentucky bluegrass
Van Engelen Zaden BV (NL)
Malus domestica (Suckow) Borkh. · Apple
Boldyzheva Liubov Dmytrivna, Kopan` Kira Mykolaivna, Kopan Volodymyr Pavlovych,
Solanum lycopersicum L. · Tomato
Giulio Bile
Salix viminalis L. · Basket willow
Gospodarstwo Rolne dr inż. Jan Wiesław Dubas
Zea mays L. subsp. mays (Sweet Corn Group) · Sweet corn
Devid Mohford
Prunus cerasus L. · Sour cherry
Uniwersytet Przyrodniczy w Poznaniu
Ribes nigrum L. · Blackcurrant
Institut Sadiwnictwa Ukrainska Akademija Agrarnich Nauk Volodymyr Kopan
Brassica napus L. · Rapeseed
MONSANTO TECHNOLOGY
Zea mays L. · Maize
Dekalb Genetics Corporation
Apium graveolens L. var. secalinum (Alef.) Mansf. · Chinese celery
Her Bemsdeburh
Daucus carota L. · Carrot
Bejo Zaden B.V.
Rosa L. · Rose
Pepinieres et Roseraies Georges Delbard| FR
Malus domestica (Suckow) Borkh. · Apple
INCONNU (FR)
Sorghum bicolor (L.) Moench · Sorghum
Karanda Tetiana Mykolaivna, Liashok Petro Hryhorovych, Barbaruk Valentyna Tadeushivna, Piter Bohdan Chykaliuk, Larri Richardson,
Beta vulgaris Sugar Beet Group · Sugar beet
Stefaan Horemans
Beta vulgaris Fodder Beet Group · Mangelwurzel
Malopolska Hodowla Roslin Spolka z o.o.
Helianthus annuus L. · Sunflower
Malinovskyi Serhii Volodymyrovych
Festuca arundinacea Schreb. · Tall fescue
Peak Plant Genetics
Solanum lycopersicum L. · Tomato
Petoseed Co INC (US)