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
Station de Recherche du Comité Nord G.I.E.
Solanum tuberosum L. · Potato
SCOTTISH RESEARCH INSTITUTE
Solanum tuberosum L. · Potato
JAMES HUTTON LTD
Solanum tuberosum L. · Potato
Sloots Aardappelkweekbedrijf B.V.
Trifolium subterraneum L. · Subterranean clover
NEW SOUTH WALES, DEP.AGR.
Solanum tuberosum L. · Potato
JAMES HUTTON LTD
Solanum tuberosum L. · Potato
J.J. Schilt
Solanum tuberosum L. · Potato
Sloots Aardappelkweekbedrijf B.V.
Glycine max (L.) Merr. · Soybean
SNOW BRAND SEED CO.LTD
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
PLANT RESEARCH INTERNATIONAL B.V.
Solanum tuberosum L. · Potato
RUP «NAUCHNO - PRAKTICHESKIJ CZENTR NACZIONALNOJ AKADEMII NAUK BELARUSI PO KARTOFELEVODSTVU I PLODOOVOSHHEVODSTVU»
Solanum tuberosum L. · Potato
Jacob Heidemans
Solanum tuberosum L. · Potato
Karsten Ellenberg
Capsicum annuum L. · Bell pepper
ESASEM SPA
Solanum tuberosum L. · Potato
Austinus Jansen
Solanum tuberosum L. · Potato
GERMICOPA UK
Vaccinium corymbosum L. · Highbush blueberry
Wagner L. Adam, Brazelton M. David
Glycine max (L.) Merr. · Soybean
University of Guelph Department of Plant Agriculture
Solanum tuberosum L. · Potato
Station Recherche du Comité Nord (GIE)
Solanum tuberosum L. · Potato
RUP «NAUCHNO - PRAKTICHESKIJ CZENTR NACZIONALNOJ AKADEMII NAUK BELARUSI PO KARTOFELEVODSTVU I PLODOOVOSHHEVODSTVU»
Malus domestica (Suckow) Borkh. · Apple
Solanum tuberosum L. · Potato
JEAN MARC ABHIVEN_
Solanum tuberosum L. · Potato
Kweek-en Researchbedrijjf Agrico B.V
Solanum tuberosum L. · Potato
Interseed Potatoes GmbH