Absorption, translocation, and fate of the herbicide, 2-(3,4- dichlorophenyl)-4-methyl-1,2,4-oxadiazolidine-3,5-dione, in cotton

Absorption, translocation, and metabolism of the ¹⁴C-labeled herbicide 2-(3,4-dichlorophenyl)-4-methyl-I,2,4-oxadiazolidine-3,5-dione (VCS-438) in cotton (Gossypium hirsutum L. 'Acala 4-42-77') were studied using autoradiography, thin-layer chromatography, and counting. Foliar penetration and acropetal distribution of 14C occurred within 3 hr and increased with time. No basipetal translocation of ¹⁴C out of treated leaves was detected after treatment. Radioactivity first occurred in the leaf veins, then more generally in interveinal tissues distally from the point of application. Absorption into roots of 30-day-old plants via nutrient solution was rapid; translocation into stem and leaves occurred 12 to 24 hr after treatment. Radioactivity was translocated more rapidly in 40-day-old plants. ¹⁴C in leaves of root-treated plants was first located in the veins, then distributed throughout with accumulation of ¹⁴C in lysigenous glands and leaf margins. Little ¹⁴C moved into young growing points; most accumulated in older leaves. Heterocyclic ring-labeled and phenyl ring-labeled VCS-438- ¹⁴C had similar distribution patterns of ¹⁴C, characteristic of compounds