Georgia Extension Vegetable News
The University of Georgia
Cooperative Extension Service
College of Agriculture and Environmental Sciences / P.O. Box 1209, Tifton, GA 31793
Trade names are for information only. The Cooperative Extension Service, The University of Georgia College of Agricultural and Environmental Sciences does not guarantee or warrant any product mentioned; neither does the use of a trade or brand imply approval of any product to the exclusion of others which may also be suitable.

Switch Gets Onion Label
Frost Damage Variable in Early Episode
Tifton Plant Disease Clinic

Switch Gets Onion Label
David Langston
Extension Vegetable Pathologist - UGA

Switch, a combination of cyprodinil (37.5%) and fludioxonil (25%), recently received a label for onions and strawberries in Georgia. This product effective primarily on Botrytis pathogens but also has activity on Alternaria spp. On onions, Switch is labeled for Botrytis leaf blight (blast) caused by Botrytis squamosa and purple blotch caused by Alternaria porri. The labeled rates for this product are from 11.0 - 14.0 oz/acre. Potential drawbacks with this fungicide are the rotational restrictions (no rotation crops other than onions and strawberries for 12 months following the last application of Switch) and the $4.00/oz price. Field trials in Georgia have shown that Switch is very efficacious on both Botrytis leaf blight and purple blotch. Attached to this newsletter should be the label for Switch.

Frost Damage Variable in Early Episode
William Terry Kelley
Extension Horticulturist

Frost damage from the late October blast that came through Georgia varied widely. The primary crops that were affected appeared to be cucumbers and snap beans. Tomatoes, pepper and of course coolerseason crops were largely unaffected. The damage was heavily dependent upon location as some areas received much more damage than others.

In most instances, cucumbers were pretty much wrapped up by the frost where they were hit. Snap beans and squash received from moderate to mild damage. Many of the beans only lost a few upper leaves and should have resumed production once temperatures moderated. Tomatoes and pepper were less impacted by the frost with only minor damage that was for the most part cosmetic in nature.

Cooler temperatures have slowed production overall on most of these crops in the last few weeks. Normal first occurrence of freezing temperatures is usually about three weeks later than the most recent frosts. For instance, in Tifton, the average occurrence of a freezing temperature is on November 20. Growing degree day accumulation has been much slower than normal during the last few weeks, however.

There was some damage on crops that normally are fairly resistant to frost damage. Collards, turnips and cabbage received some damage in the most recent event. These crops are of course generally considered cool-season crops and do not generally endure frost damage at marginal temperatures. However, prior to the low temperatures, there had not been any significantly cold weather. The cold front moved in rather rapidly following fairly moderate temperatures. Therefore, plants were not acclimated to the immediate freezing temperatures and were more predisposed to frost injury than normal.

Jason Brock
Plant Disease Diagnostician - UGA

The following is a summary of the commercial vegetable samples diagnosed since the June newsletter.

Georgia Extension Vegetable News

The Georgia Extension Vegetable News is published bimonthly for Jan-Feb, Sept-Oct, and Nov-Dec and monthly March-Aug. This newsletter is also available on the World Wide Web at www.cpes.peachnet.edu/veg or www.ugaveg.org.