DISTRIBUTION AND FATE OF ~(14)C-ACEPHATE IN TOMATO PLANTS AND SOIL

摘要

This experiment was carried out using tomato plants (3-8 weeks old) that were planted in soil inside a PVC tube (inner diameter, 8.5 cm; height, 20 cm). Ten millilitres of ~(14)C-acephate (O,S-dimethyl acetyl phosphoramidothioate) solution (0.0214 μCi/mL, 26.5 ppm) were applied to the soil. At the vegetative phase, the ~(14)C-acephate residues were higher in the older leaves than in the younger leaves. At the generative phase, 0.06% ~(14)C-acephate was detected in fruits on day 1, 0.9% on day 4, 1.5% on day 7 and 3% on day 14. The ~(14)C-acephate residues and their metabolites in soil were determined using thin layer chromatography (TLC) and gas-liquid chromatography (GLC) on a packed column of 3 % CHDMS on Chromosorb WAW. The ~(14)C-acephate results from TLC and GLC, respectively, were 51.2 and 59.1% on day 1, 24.1 and 24.5% on day 4, 11.8 and 17.1% on day 7 and 3.1 and 3.1% on day 14. The metabolite, methamidophos, showed 2.5% on day 1,9.2% on day 4, 11.3% on day 7 and 2.2% on day 14, obtained by TLC. TLC analysis showed that the acephate and methamidophos, respectively, in leaves were 3.9 and 0.8% on day 1, 4.5 and 1.5% on day 4, 7.1 and 7.5% on day 7, and 5.5 and 10.3% on day 14.