Mildiu de la cebolla
On Ca Bay Laurel in Armstrong Woods
Water, muck, and moss was taken from a temporary pond in June 2013(?). It was kept at 4C until placed in a sterile Petri dish and baited with sterile sesame seeds in August 2015. The Achlya grew in a week.
In October 2015, Olpidiopsis resting spores were observed. Additionaly sesame seeds were added to encourage growth of both organisms, and zoosporangia of releasing biflagellated zoospores, which determined the parasite to be Olpidiopsis.
On California Bay leaves.
Canker on Coast Live Oak (which is nearly dead).
Symptoms on coast live oak in Piper Park, Larkspur, Marin County. Two canker areas: free inches from ground, and at DBH. Tree appears mostly healthy.
Oomycota or oomycetes (/ˌoʊəˈmaɪsiːt/) form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms. They are filamentous, microscopic, absorptive organisms that reproduce both sexually and asexually. Oomycetes occupy both saprophytic and pathogenic lifestyles – and include some of the most notorious pathogens of plants, causing devastating diseases such as late blight of potato and sudden oak death. They are also often referred to as water molds (or water moulds), although the water-preferring nature which led to that...