Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/30/2008
Publication Date: 9/24/2008
Citation: Lancaster, S.H., Haney, R.L., Senseman, S.A., Kenerley, C.M., Hons, F.M. 2008. Microbial degradation of fluometuron is influenced by Roundup WeatherMAX. Journal of Agricultural and Food Chemistry. 56(18):8588-8593. Interpretive Summary: A popular practice among farmers is to mix 2 or more herbicides together to save the expense of separate applications. The effect on herbicide performance in soil can be affected by mixing herbicides together due to the soil microbes. We found that mixing Fluometuron (used to control grass and broadleaf weeds in cotton) and Roundup Ultra Max increased the soil microbial activity, however, Fluometuron alone did little to affect the soil microbes. The result is that tank mixing these two chemicals will cause Fluometuron to break down more readily in soil when mixed with Roundup Ultra Max.
Technical Abstract: Laboratory experiments were conducted to describe the influence of glyphosate and fluometuron on soil microbial activity and to determine the effect of glyphosate on fluometuron degradation in soil and by Rhizoctonia solani. Soil and liquid medium were amended with formulated fluometuron alone or with two rates of formulated glyphosate. Soil carbon mineralization was measured hourly for 33 d. Fluometuron remaining in the soil was quantified following 3, 6, 10, 15, 20, 30, and 40 d of incubation. Fluometuron remaining in medium and fungal biomass were measured after 1, 3, 6, 10, 15, and 20 d of incubation. The addition of glyphosate with fluometuron increased C-mineralization relative to fluometuron applied alone. Application of fluometuron with glyphosate increased the rate of fluometuron degradation relative to fluometuron alone. More fluometuron remained in media and less fungal biomass was produced when glyphosate was included.