Effective control of two genotypes of Phytophthora infestans in the field by three oxathiapiprolin fungicidal mixtures.

In two field experiments, performed in 2020 and 2021, potato Nicola plants were sprayed once with three (Exp. 1) or two (Exp. 2) doses of Zorvec Vinabel (oxathiapiprolin+ zoxamide = ZZ), Zorvec Encantia (oxathiapiprolin+ famoxadone = ZF), Zorvec Endavia (oxathiapiprolin+ benthiavalicarb = ZE), Infinito (= INF) or Mefenoxam (= MFX) and thereafter inoculated with genotype 23A1 or 36A2 of Phytophthora infestans.

Novel synergistic fungicidal mixtures of oxathiapiprolin protect sunflower seeds from downy mildew caused by Plasmopara halstedii.

Plenaris (oxathiapiprolin) applied to sunflower seedlings was highly effective in controlling downy mildew incited by the oomycete Plasmopara halstedii. In vitro assays revealed strong suppression of zoospore release and cystospore germination of P.halstedii by Plenaris.

Oxathiapiprolin-based fungicides provide enhanced control of tomato late blight induced by mefenoxam-insensitive Phytophthora infestans.

Oxathiapiprolin is a new fungicide with extremely high efficacy against oomycete plant pathogens. Solo components oxathiapiprolin (OXPT), chlorothalonil (CHT), azoxystrobin (AZ), mandipropamid (MPD), and mefenoxam (MFX) were compared with each other and with four oxathiapiprolin pre-packed fungicidal mixtures, OXPT+CHT 1+66.7, OXPT+AZ 1+10.

Seed transmission of Pseudoperonospora cubensis.

Pseudoperonospora cubensis, an obligate biotrophic oomycete causing devastating foliar disease in species of the Cucurbitaceae family, was never reported in seeds or transmitted by seeds. We now show that P. cubensis occurs in fruits and seeds of downy mildew-infected plants but not in fruits or seeds of healthy plants.