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
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Lolium perenne L. · Perennial ryegrass
Rutgers, The State University of New Jersey
Helianthus annuus L. · Sunflower
Institut za ratarstvo i povrtarstvo, Novi Sad
Helianthus annuus L. · Sunflower
Institut za ratarstvo i povrtarstvo, Novi Sad
Hordeum vulgare L. · Barley
Gesellschaft für goetheanistische Forschung e.V.
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
New Fruits, I
Daucus carota L. · Carrot
BEJO ZADEN
Helianthus annuus L. · Sunflower
Institut za ratarstvo i povrtarstvo, Novi Sad
Festuca arundinacea Schreb. · Tall fescue
PURE SEED TESTING
Daucus carota L. · Carrot
Vilmorin SA (FR)
Cucumis sativus L. · Cucumber
RIJK ZWAAN ZAADTEELT EN ZAADHANDEL B.V.
Spinacia oleracea L. · Spinach
Philip Simons
Festuca arundinacea Schreb. · Tall fescue
PURE SEED TESTING
Lolium perenne L. · Perennial ryegrass
DLF Seeds A/S
Poa pratensis L. · Kentucky bluegrass
PURE SEED TESTING
Ribes uva-crispa L. · Gooseberry
VOLUZNEV ANATOLIJ GRIGOR'EVICh
Festuca arundinacea Schreb. · Tall fescue
PURE SEED TESTING
Poa pratensis L. · Kentucky bluegrass
PICKSEED WEST INC
Hordeum vulgare L. · Barley
Anja Maasberg
Hordeum vulgare L. · Barley
KWS UK LTD
Phaseolus vulgaris L. · Common bean
Robert J. Gehin.
Hordeum vulgare L. · Barley
KWS UK LTD
Hordeum vulgare L. · Barley
KWS UK LTD
Hordeum vulgare L. · Barley
KWS UK LTD