ABSTRACT
Silicone surfactants have recently been identified as providing increased efficacy and rainfastness for the herbicide Na-acifluorfen [5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid] on velvetleaf (Abutilon theophrasti Medic.). The objectives of this study were to compare two statistical methods for determining the Na-acifluorfen application rate, identifying the most effective adjuvant, and selecting the application rate of this adjuvant necessary to provide velvetleaf control. The greenhouse study was done with and without simulated rainfall to evaluate rainfastness.
Use of the Box-Behnken design and analysis of data required only 15 treatments, compared to the 27 treatments required by a three-way factorial design and analysis. Both statistical methods identified similar treatment response trends and facilitated the identification of the most effective adjuvant treatment.
