The extraction,estimation and persistence of benodanil fungicide in tobacco tissues

The results of determinations of benodanil, extracted with acetone from freeze-dried tobacco leaves and estimated by thin-layer chromatography and bioautography, correlated well with those obtained by Soxhlet-extraction with acetone-light petroleum and determined by gas-liquid chromatography. A greater percentage of the amounts applied was usually recovered from leaves than from stems and more was always recovered 10 days after application than after 1 day. Similar changes in extractability with time were found in field samples; less was extracted from roots, stems and leaves at transplanting (2 days after treatment) than several days later. Comparatively large amounts of benodanil were present in roots, stems and leaves, 4 weeks after transplanting, and stem damage from Rhizoctonia solani was restricted.