Update on Folicure Use on Cururbits

June 8, 2001

As many of you may know, we have applied for a Section 18 Emergency Use Exemption for the use of Folicur on watermelons to reduce losses to gummy stem blight. We will NOT be granted ANY new uses for Folicur at this time or in the immediate future, therefore it is illegal to apply Folicur to watermelons or any other crop to which it is not currently labeled. We have been informed by Georgia Dept. of Ag. Pesticide Division that the EPA is not considering any new uses for Folicur at this time due to toxicity problems.

Currently, chlorothalonil products (Bravo, Echo, Equus) remain as our most consistent and effective recommendation for gummy stem blight.

If these products are used, PLEASE be sure that growers read the label that states that they should not be used under:
1) intense heat and sunlight;
2) drought conditions;
3) poor vine canopy;
4) other crop or environmental conditions which may enhance the chances for sunburn.

Do not mix chlorothalonil with anything that may enhance rind phytotoxicity. Many growers are using chorothalonil products now with no ill effects. Other fungicide options include Benlate or Topsin M tank-mixed with mancozeb products. Insensitivity of the gummy stem blight fungus to Quadris has been reported in Crisp and Sumter counties and reports of control failures are becoming more common in south Georgia. Work is currently being conducted to determine the extent of this fungicide resistance. The current rainy weather has sparked a rapid increase in the development and spread of gummy stem blight and spray programs should be shortened to at least a 7-day schedule.

David B. Langston, Jr. University of Georgia Extension Plant Pathologist-Vegetables