The Influence of Paraffinic Oil and Nonionic Surfactant on the Foliar Activity of an Aryloxyphenoxypropionate Herbicide
SourceFormulation design criteria used in the development of emulsifiable concentrate compositions containing built-in adjuvants for XRD-492-methyl are discussed. Foliar applications of radiolabelled XRD-492-methyl were made on Setaria faberi (giant foxtail) and Avena fauta (wild oats) to characterize foliar retention, uptake, and basipetal transport of 14C-activity. On the basis of 14C-activity basipetal (downward) transport data, POLYGLYCOL 26-2 was the most effective nonionic surfactant studied and in combination with paraffinic oil, a weight ratio of 2:1 paraffinic oil: POLYGLYCOL 26-2 appeared near optimum. A total adjuvant concentration in the final composition of 60 wt % in conjunction with an active ingredient concentration of 30–120 g ae/ha provided a minimum adjuvant concentration in 187 L/ha total spray volume of 0.2% (w/v) paraffinie oil and 0.1% (w/v) nonionic surfactant when the use rate (g ae/ha) was the same as the active ingredient concentration (g ae/L).