Location: Soybean and Nitrogen Fixation ResearchTitle: Atrazine, mesosulfuron-methyl, and topramezone persistence in North Carolina soils
|GANNON, TRAVIS - North Carolina State University|
|EVERMAN, WESLEY - North Carolina State University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/4/2022
Publication Date: 4/18/2022
Citation: Ramanathan, S., Gannon, T., Everman, W., Locke, A.M. 2022. Atrazine, mesosulfuron-methyl, and topramezone persistence in North Carolina soils. Agronomy Journal. 114(2):1068-1079. https://doi.org/10.1002/agj2.21041.
Interpretive Summary: Soil properties can affect the length of time that herbicides persist in soils. In the southeast US, varied soil types can lead to unintended herbicide remaining in soil that can damage subsequently planted crops. This research measured the persistence in different soil types of three herbicides that are commonly applied to corn and wheat in rotation with soybean. The persistence of all herbicides varied among soil types. To avoid unintentional crop damage, more environment specific herbicide application guidelines are needed.
Technical Abstract: Investigation into effects of soil properties on herbicide persistence can aid in evaluating herbicide carryover potential and consequent injury risk to rotational crops. Laboratory incubation experiments were conducted to quantify the persistence of atrazine, mesosulfuron-methyl, and topramezone in five soils under aerobic conditions at 23 C. Mesosulfuron-methyl persistence was also tested at 7 C, representative of winter-soil temperatures in North Carolina. Herbicide half-life was calculated by linear regression using the logarithmic form of the first-order kinetics reaction. Half-life of atrazine (37 to 73 d) and topramezone (15 to 19 d) varied among soil types. Mesosulfuron-methyl half-life varied among soil types at 7 C (8.8 to 9.8 d) and 23 C (5.4 to 5.8 d). A significant temperature effect (P < 0.01) was observed for mesosulfuron-methyl persistence within soil types. Atrazine and topramezone half-life was shortest in Candor sand (4% clay, 1.8% organic matter, 5.1 pH) and longest in Portsmouth sandy loam (13% clay, 5.3% organic matter, 4.3 pH). Mesosulfuron-methyl half-life was longer at lower soil temperature. Half-life of atrazine, mesosulfuron-methyl, and topramezone were correlated with soil organic matter (r = 0.83, -0.53, and 0.63, respectively) and soil pH (r = -0.86, 0.55, and -0.57, respectively). Additionally, atrazine and topramezone half-life was positively correlated with soil clay content (r = 0.83 and 0.71, respectively), and mesosulfuron-methyl half-life was negatively correlated with soil temperature (r = -0.97). Correlations between soil clay content, organic matter content, and pH among soil types may have also influenced herbicide persistence. Growers practicing crop rotation should consider field soil properties and the relationships between soil organic matter content, clay content, pH, soil temperature, and herbicide persistence to make suitable herbicide selections in a rotational system to prevent crop injury from herbicide carryover.