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 Golebiew sp. z o.o.
Solanum tuberosum L. · Potato
UNION TEMPORAL EMPRESAS
Solanum tuberosum L. · Potato
Averis Seeds B.V.
Solanum tuberosum L. · Potato
Vilmorin SA (FR)
Diplotaxis tenuifolia (L.) DC. · Perennial wall-rocket
ISI SEMENTI S.P.A
Solanum tuberosum L. · Potato
Instytut Hodowli i Aklimatyzacji Roslin Panstwowy Instytut Badawczy
Solanum lycopersicum L. · Tomato
Centre Tech. de Conservation des produits Agricoles (FR)/Institut National de la Recherche Agronomique (FR)
Prunus amygdalus x Prunus persica
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Solanum tuberosum L. · Potato
Hodowla Ziemniaka Zamarte sp. z o.o. - Grupa IHAR
Capsicum annuum L. · Bell pepper
Clause Semences SA (FR)
Solanum tuberosum L. · Potato
IRPT.ZAMARTE
Solanum tuberosum L. · Potato
Lietuvos agrarinių ir miškų mokslų centro Vokės filialas
Hybrids between Citrus x aurantium L. x Citrus trifoliata L.
INCONNU (FR)
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
IFAPA-INIA-FNM-NTF-FV
Nicotiana tabacum L. · Tobacco
BARTOLUCCI DANILO
Solanum tuberosum L. · Potato
MIKE LUIZA
Prunus amygdalus x Prunus persica
AGROMILLORA IBERIA S.L.U
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Flevo Plant Holding B.V.
Pyracantha coccinea M. Roem. · Firethorn
Van der Sar V.O.F.
Chamaecyparis lawsoniana (A. Murray bis) Parl. · Lawson's cypress
Carole Spicer^^^Derek Spicer
Castanea x coudercii A. Camus
Instituto Nacional de Investigação Agrária e Veterinária (INIAV) I.P.
Prunus L. · Plum
Prunus L. · Plum
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Fresh Forward Holding B.V.