Persistence of benomyl in pruned apricot sapwood

The persistence of benomyl in pruned apricot sapwood was investigated. The amount of fungi toxicant recovered from sapwood after application of 5 µg benomyl to the pruned surfaces varied at different times of the year between 90 and 25% when sampled after 2 hr and between 45 and 15% when sampled after 15 days. The amount of fungi toxicant recovered after applications of 25, 50 and 500 µg benomyl varied between 100 and 17% when sampled after 2 hr and between 67 and 12% when sampled after 15 days. No fungi toxicant was detected in bark or sapwood 0.5 cm below the treated surface or in untreated stems. Thin-layer chromatography revealed that the fungi toxicant assayed was MBC (methyl benzimidazole-2-yl carbamate).