FATE OF [C-14] MANCOZEB IN EGG PLANTS (SOLANUM-MELONGENA L) DURING SUMMER UNDER SUBTROPICAL CONDITIONS

The fungicide mancozeb belongs to ethylenebis(dithiocarbamate) group of fungicides which is used to control brown and black rust, leaf spot, leaf blight, downy mildew etc. on a variety of plants including egg plants, tomato, potato and others. [C-14]mancozeb, when applied to the foliage of egg plants (Solanum melongena L.) during summer months, dissipated very rapidly with a half-life of only 10.6 days. Ethylenethiourea (ETU), ethyleneurea (EU), ethylenethiuram disulfide (ETD), ethylenethiuram monosulfide (ETM) were the metabolites of [C-14]mancozeb detected in all the plant parts at different times after the treatment. The amount of ETU in fruits after fourteen days of treatment was only 206 mug kg-1 which is below the maximum permissible level and ultimately came down to 4.6 mug kg-1 after 42 days. EU was found to be the predominant metabolite. suggesting the breakdown of unstable ETU to relatively stable EU under subtropical conditions.