Bull. Spec. CORESTA Congress, Brighton, 1998, p. 77, AP4

Introduction and initial experiences with sulfentrazone for weed control in tobacco

University of Georgia, Tifton, GA, USA
Tobacco Research and Extension Scientists in Georgia have been evaluating sulfentrazone for weed control in tobacco in Georgia, USA for the last eight years. The United States Environmental Protection Agency granted a full label in 1997 for sulfentrazone as Spartan 75 DF for control of nutsedge, morningglory and pigweed in tobacco in the United States. The initial year of grower use included many opportunities to observe weed control efficacy, but also the results of variation in grower application methods and rates, sprayer calibration, crop tolerance, confusion with regard to Spartan 75 DF phytotoxicity symptoms and those symptoms resulting from disease, weather, and fertility problems. Examples of problems reported to have been caused by Spartan use in 1997 will be reviewed in light of subsequent investigation. Data accumulated on application rate and application methods accumulated over an eight year period for studying sulfentrazone will be reviewed. Recent research with an alternative application method which involves a directed spray of the herbicide solution with shields to protect transplanted tobacco will be presented.