Sugarcane (Saccharum sp.) growers in Louisiana report that the widely used soil residual herbicide, pendimethalin, is less effective at controlling itchgrass (Rottboellia chochinchinensis), possibly through accelerated dissipation from repeated applications. Some growers have started to use another herbicide, clomazone, in place of pendimethalin for itchgrass control when pendimethalin does not provide the necessary control. Little is known about the dissipation of these two herbicides, especially when applied together, in diverse sugarcane soils in Louisiana. Thus, the objective of the research was to measure the dissipation of pendimethalin and clomazone in soils having high itchgrass pressure. Soil samples from five fields were fortified (4 μg g⁻¹) with clomazone and pendimethalin and monitored over the course of 163 days under laboratory conditions. Herbicide levels were determined by extracting the herbicides from soil with acetonitrile and analyzing the extracts with high performance liquid chromatography (HPLC).

中文翻译：

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土壤施用残留除草剂二甲戊灵和氯马酮在路易斯安那州甘蔗中的土壤消散和对瘟草的功效


路易斯安那州的甘蔗 （Saccharum sp.） 种植者报告说，广泛使用的土壤残留除草剂二甲戊灵在控制瘟草 （Rottboellia chochinchinensis） 方面效果较差，可能是由于重复施用会加速消散。当二甲戊素不能提供必要的控制时，一些种植者已经开始使用另一种除草剂氯马灵代替二甲戊灵来控制痘草。人们对这两种除草剂在路易斯安那州不同甘蔗土壤中的消散知之甚少，尤其是当它们一起施用时。因此，该研究的目的是测量二甲戊灵和氯马酮在高 itchgrass 压力土壤中的耗散。用氯马酮和二甲戊灵对来自五块田地的土壤样品 （4 μg ^g-1） 进行强化，并在实验室条件下监测 163 天。通过用乙腈从土壤中提取除草剂并用高效液相色谱 （HPLC） 分析提取物来确定除草剂水平。