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Nice weekend weather!

It has been a very sunny weekend in 70's. I can take this anytime.

Last night, RH was 4-50% and temperature was around 64F. I think it was little too dry for downy mildew to be happy. Speaking of disease, I found some leaves and canes showing an initial symptom development of Phomopsis today. We have untreated vines for disease observations, and I'm hoping that these vines will provide us nice cases of diseases throughout the season.


The hard-to-see dark spots with yellow hallo are from Phomopsis infection on leaf. If you take a look at shoots, what you see is:
Small necrotic spots (around the center) which can be expand later in the season. Dr. Mike Ellis' group at the Ohio State is currently working on the infection process of this fungus. Based on observations on the production of the fruiting structure in my previous experiments, it looks like this fungus can spread underneath the epidermal tissue even if we do not see clear symptoms. At which point the spread occur is not known yet.

Our Chardonnay were about 9-100% 10-inch (E-L 12) and Cabernet sauvignon was about 7-80% 5~7-inch (E-L 12) as of noon today.

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