Centennial Gold
ActiveRhododendron L. · Azalea
BOOMTEELTPRAKTIJKONDERZOEK
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.
Rhododendron L. · Azalea
BOOMTEELTPRAKTIJKONDERZOEK
Geranium maculatum L. · Spotted geranium
Tyssowski Carol / Tyssowski Carol
Helleborus x ericsmithii
Josef Heuger
Ribes nigrum L. · Blackcurrant
VOLODINA YEKATARINA V.^^^KHOTIMSKAYA SVETLANA P.^^^TIKHONOVA OLGA A.
Phlox paniculata L. · Garden phlox
Ditoplant Export B.V.
Echinacea Moench. · Coneflower
Ren Jianping
Malus domestica (Suckow) Borkh. · Apple
National Agriculture and Food Research Organization (NARO)
Hibiscus coccineus x Hibiscus moscheutos L.
Zwetzig Gretchen
Vitex agnus-castus L. · Chaste tree
Roberts David Jonathan,Schulze Justin,McBee Oren
Lagerstroemia L. · Crape Myrtle
Michael A. Dirr^^^Rhonda Helvick^^^Joshua H. Kardos^^^Oren McBee
Beta vulgaris Garden Beet Group · Garden beet
Bejo Zaden B.V.
Papaver orientale L. · Oriental poppy
Peek Eleonore|Oudelande, NL
Hybrids between Echinacea purpurea (L.) Moench and Echinacea paradoxa (Norton) Britton
HARINI KORLIPARA
Ribes nigrum L. · Blackcurrant
SCOTTISH CROP RESEARCH INSTITUTE
Magnolia L. · Magnolia
Vance Hooper
Campanula punctata Lam. · Spotted bellflower
TERRA NOVA NURSERIES INC
Rhododendron L. · Azalea
Jan Ciepłucha
Tiarella L. · Foamflower
Janet N. Egger
Ribes nigrum L. · Blackcurrant
SCOTTISH CROP RESEARCH INSTITUTE
Lolium perenne L. · Perennial ryegrass
MOMMERSTEEG INTERNATIONAL
Ilex crenata Thunb. · Japanese holly
van Nijnatten Andre Franciscus
Echinacea purpurea (L.) Moench · Purple coneflower
IT Saul Plants LLC
Hybrids between Echinacea purpurea (L.) Moench and Echinacea paradoxa (Norton) Britton
Saul Robert|Atlanta, GA, US
Zea mays L. subsp. mays (Maize Group) · Maize
Coop de Pau SCA (FR)