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.
Capsicum annuum L. · Bell pepper
TAKII EUROPE B V
Solanum lycopersicum L. · Tomato
PlantiCo Hodowla i Nasiennictwo Ogrodnicze Golebiew sp. z o.o.
Solanum tuberosum L. · Potato
Pomorsko Mazurska Hodowla Ziemniaka Sp.z o.o. z siedziba w Strzekecinie
Solanum tuberosum L. · Potato
Stacja Hodowli Roślin Przedsiębiorstwo Państwowe - Strzekęcin
Solanum tuberosum L. · Potato
Pomorsko Mazurska Hodowla Ziemniaka Sp.z o.o. z siedziba w Strzekecinie
Fragaria L. · Strawberry
Sanford, John C.|Geneva, NY / Ourecky, Donald K.|Lauderdale Lakes, FL / Reich, Jack E.|II, Geneva, NY
Solanum tuberosum L. · Potato
Germicopa Breeding S.A.S
Allium porrum L. · Leek
Hazera Seeds B.V.
Solanum tuberosum L. · Potato
PAWLAK| Dr. Pawlak c/o Hodowla Ziemniaka Zamarte Sp. z.o.o.
Solanum tuberosum L. · Potato
JEAN-MARC ABIVEN
Solanum lycopersicum L. · Tomato
OOO NPF 'AGROSEMTOMS'
Solanum tuberosum L. · Potato
WERKMAN| Fritz Werkman c/o Stet & Slot
Solanum tuberosum L. · Potato
Bretagne-Plants S.C.I.C.A.
Solanum tuberosum L. · Potato
Kweek- en Researchbedrijf Agrico B.V.
Solanum tuberosum L. · Potato
Robert Plaisted, Cornell University Agricultural Experiment Station
Solanum tuberosum L. · Potato
JEAN-MARC ABIVEN
Solanum lycopersicum L. · Tomato
GRAINES GAUTIER, S.A.
Solanum tuberosum L. · Potato
SIM W (GB)
Solanum tuberosum L. · Potato
NORDOSBAYERISCHER (DE)
Solanum lycopersicum L. · Tomato
Bayer Holland B.V.
Solanum tuberosum L. · Potato
Rolimpex (PL)
Solanum tuberosum L. · Potato
Grocep S.I.C.A.
Solanum tuberosum L. · Potato
Niederösterreichische Saatbaugenossenschaft reg.Gen.m.b.H.
Solanum tuberosum L. · Potato
P H SMEENGE