Eucalyptus harvests generate residues that remain on the soil and affect the efficacy of preemergent herbicides in the following planting cycle. The objective of this work was to evaluate the dynamics of flumioxazin, sulfentrazone, and isoxaflutole herbicides applied on different amounts and compositions of eucalyptus harvest residues subjected to different rainfall depths; and evaluate the weed control effectiveness of these herbicides when applied under these conditions. A LC–MS/MS system was used for the evaluations and the results showed that a cumulative rainfall of 50 mm was sufficient for the maximum removal of herbicides from the eucalyptus residues, regardless of the residue composition. The amount of the flumioxazin, sulfentrazone, and isoxaflutole herbicides that reached the soil was lower in the treatment with the highest amount of eucalyptus harvest residue used (40 Mg ha⁻¹). The greatest amount of herbicide reaching the soil was found with the use of 15 Mg ha⁻¹ of residues without presence of bark. The highest amount of residue used (40 Mg ha⁻¹) reduced the control of Brachiaria decumbens by sulfentrazone and isoxaflutole. The control of Commelina benghalensis was inefficient (> 80%) in the treatment with 15 Mg ha⁻¹ of residues without barks, regardless of the herbicide. Sulfentrazone controlled Ipomoea grandifolia (> 90%) under the evaluated residue conditions. Spermacoce latifolia and Sida rhombifolia were controlled by all herbicides in the evaluated residue conditions. Isoxaflutole controlled Panicum maximum in all residue conditions. The choice between the herbicides depends on the residue condition, rainfall regime, and weed species to be controlled.

中文翻译：

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亚磺草胺，氟米沙星和异恶草酮除草剂对桉树收获残余物的动力学和功效

桉树收获物会残留在土壤中，并在接下来的种植周期中影响发芽前除草剂的功效。这项工作的目的是评估氟米沙星，次磺tra和异恶草酮除草剂在不同降雨深度下对不同数量和组成的桉树收获残余物的动态变化。并评估在这些条件下施用这些除草剂的除草效果。使用LC-MS / MS系统进行评估，结果表明，无论残留物的成分如何，50 mm的累积降雨足以最大程度地从桉树残留物中去除除草剂。氟米沙星，次磺zone，^-1）。通过使用15 Mg ha ^-1的残留物而没有树皮，发现进入土壤的除草剂量最大。所使用的最高残留量（40 Mg ha ^-1）降低了次磺脲和异恶草酮控制对臂形臂虫的控制。在使用15 Mg ha ^-1的残留物且没有树皮的情况下，无论使用哪种除草剂，孟加拉Commelina的防治效率均不高（> 80％）。在评估的残留条件下，Sulfentrazone控制的大叶番薯（> 90％）。阔叶植物和Sida rhombifolia在评估的残留条件下，所有除草剂均控制了这些化合物。在所有残留条件下，异恶草酮控制的Panicum最大值。除草剂之间的选择取决于残留条件，降雨状况和要控制的杂草种类。