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.
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Beta vulgaris Sugar Beet Group · Sugar beet
SYNGENTA SEEDS, A.B.
Hordeum vulgare L. · Barley
Boreal Plant Breeding
Triticum aestivum L. · Bread wheat
Danko Hodowla Roslin Sp.z.o.o.
Hordeum vulgare L. · Barley
LAUBACH| NORDSAAT Saatzucht GmbH Herrn Dr. Eberhard Laubach - Zuchtstation Gudow -
Triticum aestivum L. · Bread wheat
Gesellschaft für goetheanistische Forschung e.V.
Hordeum vulgare L. · Barley
Danko Hodowla Roslin Sp.z.o.o.
Hordeum vulgare L. · Barley
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Trifolium incarnatum L. · Crimson clover
Delta and Pine Land Company
Festuca arundinacea Schreb. · Tall fescue
COLUMBIA SEEDS LLC
Avena nuda L. · Naked oat
NARODNE POLNOHOSPODARSKE
Capsicum annuum L. · Bell pepper
NAIK, H
Festuca arundinacea Schreb. · Tall fescue
Rutgers University
Beta vulgaris Sugar Beet Group · Sugar beet
WIELKOPOLSKA HODOWLA BURAKA CUKROWEGO SP.Z.O.O
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Walther Faedi^^^Gianluca Baruzzi^^^Paolo Sbrighi^^^Pierluigi Lucchi
Festuca arundinacea Schreb. · Tall fescue
PROF. DR. DIRK REHEUL /DR. IR. MATHIAS COUGNON
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
New Fruits, I
Hordeum vulgare L. · Barley
Saatzucht Donau GmbH & Co.KG
Fragaria L. · Strawberry
Mr. Jimmy Haig Bagdasarian
Poa pratensis L. · Kentucky bluegrass
The Scotts Company
Beta vulgaris Sugar Beet Group · Sugar beet
Syngenta Crop Protection,CH
Phaseolus vulgaris L. · Common bean
Pop Vriend Research B.V.
Beta vulgaris Sugar Beet Group · Sugar beet
STRUBE D&S GmbH, DE
Brassica oleracea L. (Savoy Cabbage Group) · Savoy cabbage
Syngenta Crop Protection AG