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 lycopersicum L. · Tomato
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Solanum lycopersicum L. · Tomato
Przedsiebiorstwo Nasiennictwa Ogrodniczego i Szkolkarstwa Spolka Akcyjna w upadlosci likwidacyjnej
Solanum tuberosum L. · Potato
MIKE LUIZA
Solanum tuberosum L. · Potato
DUBININ SERGEJ VLADIMIROVICh / SEREGINA NADEZhDA IVANOVNA / ShANINA ELENA PETROVNA
Solanum tuberosum L. · Potato
Pomorsko Mazurska Hodowla Ziemniaka Sp.z o.o. z siedziba w Strzekecinie
Solanum tuberosum L. · Potato
Pomorsko Mazurska Hodowla Ziemniaka Sp.z o.o. z siedziba w Strzekecinie
Solanum tuberosum L. · Potato
Grocep S.I.C.A.
Solanum tuberosum L. · Potato
Averis Seeds B.V.
Solanum tuberosum L. · Potato
Station du Comite Nord (FR)/Groupement Interprofessionel de la Pomme de Terre (FR)
Solanum tuberosum L. · Potato
P Y VAN DER WERFF/DE ZPC
Solanum tuberosum L. · Potato
HERMEZIU RADU
Capsicum annuum L. · Bell pepper
UNITED GENETICS ITALIA S.P.A
Fragaria L. · Strawberry
Egbertus Joseph Meulenbroek
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
The Board of the University of Arkansas (US)
Capsicum annuum L. · Bell pepper
RAMIRO ARNEDO, S.A.
Solanum tuberosum L. · Potato
Alice Anderfeld 90%, Harri Hindoalla 10%
Solanum tuberosum L. · Potato
DANESPO A/S
Solanum tuberosum L. · Potato
HZPC Holland B.V.
Solanum lycopersicum L. · Tomato
Syngenta Crop Protection AG
Solanum tuberosum L. · Potato
Germicopa SAS, FR
Capsicum annuum L. · Bell pepper
HM.CLAUSE
Solanum tuberosum L. · Potato
Norika Nordring-Kartoffelzucht-und Vermehrungs- GmbH Gros Lusewitz
Solanum lycopersicum L. · Tomato
Domaine Public (FR)
Glycine max (L.) Merr. · Soybean
Minnesota Agricultural Experiment Station