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
W.WALLMULLER
Solanum tuberosum L. · Potato
BOERHAVE VOF
Solanum tuberosum L. · Potato
SAATZUCHT FIRLBECK GMBH&CO.KG
Solanum lycopersicum L. · Tomato
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Solanum tuberosum L. · Potato
Vesa Velhartice a.s.
Solanum lycopersicum L. · Tomato
HEBREW UNI/HAZERA
Solanum tuberosum L. · Potato
Europlant Innovation GmbH & Co. KG
Solanum tuberosum L. · Potato
Sloots Aardappelkweekbedrijf B.V.
Medicago sativa L. · Alfalfa
Seed Technology & Marketing Pty Ltd. (S.T.M.)
Solanum tuberosum L. · Potato
Teagasc
Solanum tuberosum L. · Potato
SAKA PFLANZENZUCHT GMBH AND CO KG
Solanum lycopersicum L. · Tomato
Syngenta Seeds B.V.
Malus Mill. · Apple
MICHIELSEBS LUDOVICUS JACOBUS ELESABETH
Solanum tuberosum L. · Potato
The James Hutton Institute
Solanum tuberosum L. · Potato
Lars Naested
Solanum tuberosum L. · Potato
Station du Comite Nord (FR)
Solanum tuberosum L. · Potato
Pomorsko Mazurska Hodowla Ziemniaka Sp.z o.o. z siedziba w Strzekecinie
Solanum tuberosum L. · Potato
Johanna Anny Pruim-van Loon^^^Hubrecht Jan van Loon^^^Anthonie Elbert van Loon^^^Elbertus Marius van Loon^^^Jan Pieter van Loon^^^Johanna Wilhelmina Maatje van Loon-Kloet
Solanum tuberosum L. · Potato
J.M. Kannegieter, H.Kannegieter,
Solanum tuberosum L. · Potato
C.J.J. Laan, A.S.J. Laan,
Solanum tuberosum L. · Potato
Lars Naested
Glycine max (L.) Merr. · Soybean
Sylvain Legay
Solanum tuberosum L. · Potato
IPR BV
Solanum tuberosum L. · Potato
Germicopa Breeding