Dissipation of the fungicide tetraconazole from field-sprayed sugar beets

The reduction of tetraconazole residue levels in field sugar beets (roots a nd foliage) was investigated, and the effectiveness of this new fungicide a gainst the leaf spot disease of sugar beet was evaluated. The fungicide was used according to the recommended application procedures. Sugar beets rece ived five applications of tetraconazole at rates of 0.05 and 0.10 kg of act ive ingredient/ha. A multiresidue method was adapted, and tetraconazole res idues were determined with gas chromatography using a wide-bore column and an electron capture detector. Recovery of tetraconazole from sugar beet roo ts and leaves was found in the range of 86-111 and 78-103%, and the detecti on limits were estimated as 0.001 and 0.002 mg/kg, respectively. A relative ly rapid dissipation rate of tetraconazole residues was found with a half-l ife of 5 days for either sugar beet roots or foliage.