Determination of Herbicide Residues in Edible Taro Parts and Wetland Flood Waters

Abstract

A preliminary experiment with seven preemergence herbicides identified oxyfluorfen as a promising herbicide for commercial taro (Colocasia esculenta) production in Hawaii. Oxyfluorfen was applied twice at 0.38, 0.56 and 1.11 kg/ha to taro grown under wetland flooded and upland conditions. No oxyfluorfen residues were found in plant tissues (limit of detection 0.02 ppm). Oxyfluorfen levels in water from treated lowland plots was determined. Trace levels present in flood waters immediately after treatment dissipated to undetectable levels (limit of detection, 0.001 ppm) within 24 hours.