Plasmopara viticola

Plasmopara viticola is a plant pathogen.

Plasmopara viticola, causal agent of grapevine downy mildew, is a heterothallic oomycete that overwinters as oospores in the leaf litter and soil. In the spring, oospores germinate to produce macrosporangia, which under wet conditions release zoospores. Zoospores are splashed by rain into the canopy, where they swim to and infect through stomata. After 7-10 days, yellow lesions appear on foliage. During favorable weather, the lesions sporulate and new secondary infections occur (Kennelly et al., 2006)

For more information: http://fag.mnd.fh-wiesbaden.de/pdf/Rumbou-Gobbin%20Plasmopara%20viticola.pdf