Abstract: To study the transport and metabolism of glyphosate, different doses of glyphosate were quantitatively sprayed into young and adult tea plants (Young: 0.9 g·m^-2. Adult: 1.5 g·m^-2, 4.5 g·m^-2 and 15 g·m^-2) and samples were collected at different times (1, 4, 7, 15 d and 40 d) to determine the contents of glyphosate and its main metabolite aminomethylphosphonic acid in various parts of tea plants. The results show that the order of glyphosate content in tea plants from high to low was root, leaf and stem after spraying glyphosate on the root of tea plant. Aminomethylphosphonic acid was mainly accumulated in the roots of tea plants, and it could also be detected in the stems and leaves of young tea plants (0-0.33 mg·kg^-1). However, no aminomethylphosphonic acid was detected in the stems and leaves of adult tea plants. After 40 d of application, glyphosate and aminomethylphosphonic acid were not detected in the roots, stems and leaves of young tea plants at a dose of 0.9 g·m^-2. However, they were still detected in the roots of adult tea plants at a dose of 1.5-15 g·m^-2 (glyphosate: 2.26-26.73 mg·kg^-1, aminomethylphosphonic acid: 0.21-2.59 mg·kg^-1). Glyphosate residues in both stem and leaves of adult plants were low (0-0.29 mg·kg^-1). In this study, through field simulation experiments, the transfer, metabolism and enrichment rules of glyphosate in tea plants after being ingested were analyzed, which could provide a reference for scientific control and risk assessment of glyphosate in tea gardens.

Key words: Camellia sinensis, glyphosate, aminomethylphosphonic acid, residue, distribution