Diseases
Cucumis sativus L.
A fungal disease of cucumber caused by the obligate parasite Pseudoperonospora cubensis. It is characterized by the appearance of angular chlorotic spots on leaves and a distinctive layer of sporulation on the underside of the leaf.
In the reference 394 varieties crop Cucumber, where this is mentioned in the description.
The causative agent of the disease is the oomycete Pseudoperonospora cubensis, which exhibits high variability, leading to the emergence of new aggressive pathotypes and the overcoming of breeding resistance. Symptoms manifest as angular yellowish-green spots on the upper side of the leaf, which eventually turn brown and coalesce. A diagnostic feature under high humidity is the appearance of a grayish-violet or whitish layer of sporulation on the underside of the leaf blade.
In southern regions, the disease can occur in a latent form, manifesting as small chlorotic spots, which complicates visual diagnosis. The consequences of the infection include premature drying and shedding of leaves, deterioration of fruit marketability, and plant death. When cucumber plantings are affected, the fruits lose their taste qualities and characteristic coloration.
For breeding resistant varieties, Dm genetic markers are used, including the specific genes Dm1.1, Dm5.1, Dm5.3 and the non-specific STAYGREEN (CsSGR) gene. The historically significant dm-1 gene has ceased to provide protection due to the evolution of the pathogen. In the international classification of varieties, resistance to the pathogen is labeled with the Pcu code, divided into HR (high) and IR (intermediate) levels.
General information about the subject — on the page Downy mildew.
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.
Cucumis sativus L. · Cucumber
Serhiienko Oksana Volodymyrivna, Diachenko Nina Mykolaivna, Pozniak Oleksandr Vasylovych, Shevchenko Olena IUriivna, Ptukha Nadiia Ivanivna,
Cucumis sativus L. · Cucumber
ROYAL SLUIS
Cucumis sativus L. · Cucumber
Bakumenko Nadiia Vasylivna, Pluzhnikova Liudmyla IEhorivna, Petrenko Mariia Petrivna, Kryvets` Dmytrii Olehovych, Pozniak Oleksandr Vasyl`ovych,
Cucumis sativus L. · Cucumber
Jan Prasil
Cucumis sativus L. · Cucumber
Khokhlova Nataliia Oleksiivna, Ivanova Anna Pavlivna, Suchkova Liubov Vasylivna,
Cucumis sativus L. · Cucumber
Her Bemsdeburh
Cucumis sativus L. · Cucumber
(Ulveczki Gabriella), (Dr.Szarka Janos), (Balogh Peter),
Cucumis sativus L. · Cucumber
Asgrow Seed Company (US)
Cucumis sativus L. · Cucumber
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Cucumis sativus L. · Cucumber
Shevkunov Valerii Mykolaiovych, Prutens`ka Nataliia Oleksiivna, Shamshyna Anna Viacheslavovna, Portiankin Alieksiei IEvhenovych, Havrysh Serhii Fedorovych,
Cucumis sativus L. · Cucumber
Havrysh Serhii Fedorovych, Dubinin Serhii Volodymyrovych,
Cucumis sativus L. · Cucumber
Krylov Oleh Mykolaiovych, Borysov Oleksandr Volodymyrovych,
Cucumis sativus L. · Cucumber
Vovk Zhanna Mykolaivna
Cucumis sativus L. · Cucumber
Harris Moran Seed Company (USA) (US)
Cucumis sativus L. · Cucumber
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Cucumis sativus L. · Cucumber
Hans Briuer
Cucumis sativus L. · Cucumber
Shamshyna Anna Viacheslavovna, Portiankin Alieksei Evhenovych, Havrysh Serhii Fedorovych,
Cucumis sativus L. · Cucumber
Andzhei Rostvorovskyi
Cucumis sativus L. · Cucumber
INTERSEMILLAS SAU
Cucumis sativus L. · Cucumber
TAKII EUROPE B V
Cucumis sativus L. · Cucumber
Shevchenko Andrii Oleksiiovych
Cucumis sativus L. · Cucumber
FGUP ,,Volgogradsortsemovošč"
Cucumis sativus L. · Cucumber
Krylov Oleh Mykolaiovych, Borysov Oleksandr Volodymyrovych,
Cucumis sativus L. · Cucumber
Arkadiusz Labrzycki