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 x ananassa Duchesne ex Rozier · Garden strawberry
Lenkijos sodininkystės ir gėlininkystės institutas
Hordeum vulgare L. · Barley
Sejet Planteforaedling I,S
Triticum aestivum L. · Bread wheat
Výzkumné Centrum Selton s.r.o., Selgen A.S.
Hordeum vulgare L. · Barley
LOCHOW-PETKUS
Fragaria L. · Strawberry
Sort ie suspil`nym nadbanniam
Beta vulgaris Sugar Beet Group · Sugar beet
DLF Beet Seed APS
Lolium multiflorum Lam. var. westerwoldicum Wittm. · Westerwolds Ryegrass
Carneau Freres SA Eurogazon (FR)
Cucumis sativus L. · Cucumber
Harris Moran Seed (US)
Solanum tuberosum L. · Potato
MEYER WILHELM| Wilhelm Meyer in Fa. Golden Geest Kartoffel Erzeuger-gesellschaft mbH
Solanum lycopersicum L. var. lycopersicum · Tomato
Syngenta Seeds B. V.
Beta vulgaris Sugar Beet Group · Sugar beet
Societe Europeenne de Semences NV/SA (BE)
Beta vulgaris Sugar Beet Group · Sugar beet
KWS Saat AG, DE
Beta vulgaris Sugar Beet Group · Sugar beet
Jan Sels
Solanum lycopersicum L. · Tomato
Centre Tech. de Conservation des produits Agricoles (FR)/Institut National de la Recherche Agronomique (FR)
Beta vulgaris Garden Beet Group · Garden beet
Bejo Zaden BV (NL)
Solanum lycopersicum L. · Tomato
PETOSEED CO
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Beta vulgaris Sugar Beet Group · Sugar beet
Henning Friehe
Allium porrum L. · Leek
Enza Zaden Beheer B.V.
Brassica napus var. napus · Rapeseed
Hodowla Roslin Smolice Sp.z o.o Grupa IHAR
Solanum lycopersicum L. · Tomato
Garden Seeds B.V.
Beta vulgaris Sugar Beet Group · Sugar beet
Syngenta Seeds
Beta vulgaris Sugar Beet Group · Sugar beet
SESVANDERHAVE, N.V./S.A.