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.
Beta vulgaris Sugar Beet Group · Sugar beet
SESVANDERHAVE NV-SA, BE
Festuca arundinacea Schreb. · Tall fescue
PURE SEED TESTING
Cucumis sativus L. · Cucumber
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Rubus idaeus L. · Red raspberry
SCOTTISH CROP RESEARCH INSTITUTE
Beta vulgaris Sugar Beet Group · Sugar beet
SESVANDERHAVE N.V./S.A.
Hordeum vulgare L. · Barley
W. von Borries-Eckendorf GmbH & Co.KG
Hordeum vulgare L. · Barley
Hodowla Roslin Smolice Sp.z o.o Grupa IHAR
hybrids between Prunus davidiana and Prunus persica
Solanum lycopersicum L. · Tomato
HAZERA SEEDS BV
Solanum lycopersicum L. · Tomato
HAZERA SEEDS BV
Solanum lycopersicum L. · Tomato
Sakata Vegetables Europe S.A.S
Beta vulgaris Sugar Beet Group · Sugar beet
KUTNOWSKA HODOWLA BURAKA CUKROWEGO Sp.z o.o.
Solanum lycopersicum L. · Tomato
CAPITAL GENETIC EBT, S.L.
Beta vulgaris Sugar Beet Group · Sugar beet
MariboHilleshög ApS,DK
Hordeum vulgare L. · Barley
DEUTSCHE SAATGUTGESELLSCHAFT
Solanum lycopersicum L. · Tomato
HAZERA SEEDS BV
Prunus cerasus L. · Sour cherry
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Cucumis sativus L. · Cucumber
PlantiCo Hodowla i Nasiennictwo Ogrodnicze Golebiew sp. z o.o.
Beta vulgaris Sugar Beet Group · Sugar beet
SAS Florimond Desprez Veuve & Fils
Beta vulgaris Sugar Beet Group · Sugar beet
DLF Beet Seed APS
Beta vulgaris Sugar Beet Group · Sugar beet
Florimond Desprez Veuve et Fils, FR
Beta vulgaris Sugar Beet Group · Sugar beet
Florimond Desprez Veuve et Fils, FR
Beta vulgaris Sugar Beet Group · Sugar beet
Florimond Desprez Veuve et Fils, FR
Solanum lycopersicum L. · Tomato
Clause Tezier, FR