Can soil detoxifiers mitigate crop injury from residual herbicides?

Abstract

Sugarbeet ( Beta vulgaris L.) growers have limited herbicide options for in‐crop application, so they rely on weed control in rotational crops to minimize weed problems. Sugarbeet is sensitive to many herbicides used in corn ( Zea mays L.), a common rotational crop, which effectively reduces weed control options elsewhere in the rotation. Multiple products are being marketed for their ability to “detoxify” the soil, potentially shortening the rotation interval and increasing herbicide options available in sugarbeet rotations. This study was conducted to evaluate the effectiveness of two soil detoxifiers to reduce sugarbeet injury due to soil residual herbicides. Field studies were established in 2023 in southeast Wyoming, where herbicides were applied to the soil, followed by two soil detoxifiers. Herbicide treatments included a premix of atrazine, mesotrione, bicyclopyrone, and S‐metolachlor, a stand‐alone atrazine product, and a stand‐alone mesotrione product, applied with a log‐sprayer at rates ranging from the full recommended rate to 1.6% of the recommended rate plus a non‐treated control. Soil detoxifiers were applied at the full recommended rate 22 days after herbicide application, and then sugarbeet was planted 36 days after the soil detoxifier application. Sugarbeet stand was counted 21 and 28 days after planting. Data were analyzed with a nonlinear regression, and ED ₁₀ values (effective herbicide dose causing 10% sugarbeet stand reduction) were estimated for each herbicide with and without the application of the soil detoxifier. Sugarbeet density decreased as herbicide rates increased. Neither soil detoxifier had any impact on sugarbeet stand in response to the herbicides.