6.06.14 Some Reports of Botrytis Blossom Blight and Frost

Botrytis infection of flowers showing short “hairs”

There have been some reports of localized patchy frost damage the last week of May followed by Botrytis symptoms showing up this week. Frost will make blossoms more susceptible to Botrytis infection.  I have heard this from growers in the Union area and around the Orland area. In one field, we saw low levels of both frost and Botrytis infection on the blossoms. One of the differences to previous years was the very short hairs of the Botrytis sticking out of the base of infected blossoms. A hand lens will be needed to see this kind of Botrytis infection.   Please look at previous reports to see pictures of these different diseases.

The rain over the last two days, Wednesday, June 4 to Friday, June 6 produced moderate to high risk of Botrytis infection across monitored blueberry areas.   Many growers are nearing the end of bloom, so there is little risk of further Botrytis infection that will impact the crop.