Diseases
Phytophthora infestans
Late blight is a dangerous disease of solanaceous crops caused by an oomycete, which manifests as the appearance of spots on leaves, stems, and tubers. The development of the disease is triggered by high humidity and moderate temperatures, which can lead to significant crop losses.
Mentioned in descriptions 6 798 varieties reference book.
Affected plants develop dirty-brown spots, often accompanied by a whitish mold on the underside of the leaf, while elongated dark-brown spots appear on the stems. Tubers show hard, sunken brown spots, and the internal tissue exhibits a characteristic rust-brown discoloration upon cutting.
Epiphytotics develop under conditions of high air humidity around 90% and alternating warm days with cool nights. The presence of free moisture, such as dew or fog, is a critical factor for rapid spore germination, which allows the infection to spread across the field in 10–15 days.
In breeding, a distinction is made between specific vertical resistance, controlled by R-genes, and field horizontal resistance, which is considered more reliable due to its polygenic nature and ability to slow down pathogen development. Varieties are evaluated using a 9-point scale; however, the resistance level of the foliage does not always coincide with that of the tubers, requiring comprehensive analysis during variety testing.
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 tuberosum L. · Potato
PLANT BREEDING INTERNATIONAL CAMBRIDGE
Solanum tuberosum L. · Potato
Kweek- en Researchbedrijf Agrico BV
Solanum tuberosum L. · Potato
HANS JURGEN EVERS (T)
Solanum tuberosum L. · Potato
Stacja Hodowli Roślin Stawiski
Solanum lycopersicum L. · Tomato
De Ruiter Seeds, NL
Solanum tuberosum L. · Potato
LENNART ERJEFÄLT^^^BÖÖS ULLA
Solanum tuberosum L. · Potato
HZPC Holland B.V.
Solanum tuberosum L. · Potato
VEB SAAT
Solanum tuberosum L. · Potato
WOLF & WOLF B.V.
Solanum tuberosum L. · Potato
VOGEL JOSEF| Dr. Josef Vogel
Solanum tuberosum L. · Potato
Kartoffelzucht Böhm GmbH & Co. KG (DE)
Solanum tuberosum L. · Potato
NORIKA NORDRING-KARTOFFELZUCHT UND VERMEHRUNGS-GMBH
Solanum tuberosum L. · Potato
Yosef Fohel`
Solanum tuberosum L. · Potato
Kweekbedrijf-Zpc (NL)
Solanum tuberosum L. · Potato
SMEENGE| Piet Smeenge / SMEENGE ALBERT| Albert Smeenge
Solanum tuberosum L. · Potato
Wilhelm Meyer in Fa. Golden Geest Kartoffel Erzeuger- gesellschaft mbH
Solanum tuberosum L. · Potato
WESTON JW (US)
Solanum tuberosum L. · Potato
PBI Cambridge (GB)
Malus domestica (Suckow) Borkh. · Apple
Solanum tuberosum L. · Potato
Sloots Aardappelkweekbedrijf B.V.
Solanum tuberosum L. · Potato
VAN RIJN-KWS B.V.
Solanum tuberosum L. · Potato
Lantmõnnen Seed B.V.
Solanum tuberosum L. · Potato
SAKA PFLANZENZUCHT GMBH AND CO KG
Solanum tuberosum L. · Potato
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