UPTAKE, TRANSLOCATION, AND METABOLISM OF 3,4-DICHLOROANILINE IN SOYBEAN AND WHEAT PLANTS

The roots of 13-day-old soybean (Glycine max L.) and 7-day-old wheat ( Triticum aestivum L.) hydroponic plants were exposed to [C-14]-3,4-dic hloroaniline (1.0 and 0.4 mg/l (6.2 and 2.5 mu M), respectively) and h arvested after 48/120 h (soybean) and 72 h (wheat). Both species metab olized the xenobiotic almost quantitatively to N-(beta-D-glucopyranosy l)-3,4-dichloroaniline, N-malonyl-3,4-dichloroaniline, onyl-N-(beta-D- glucopyranosyl)-3,4-dichloroaniline and non-extractable residues. In t he soybean experiments 58.8 (45 h) and 54.6% (120 h) of the applied ra dioactivity were found in the nutrient; this fraction consisted primar ily of N-malonyl-3,4-dichloroaniline. 37.3/24.1% (48/120 h) were detec ted in the plants. In the soybeans, 36.2 and 52.7% (48/120 h) of the a bsorbed C-14 were translocated, mainly into hypocotyls, primary and se condary leaves. After 120 h, the main metabolite was N-malonyl-3,4-dic hloroaniline (38.5%); considerable levels of this metabolite accumulat ed in the primary and secondary leaves (10.4 and 10.4%). The glucoside s were mainly found in the roots of the soybean plants. Totals of 23.5 and 35.1% (48/120 h) were transformed to non-extractable residues. In wheat, 78.3% of the applied 3,4-dichloroaniline was absorbed after 72 h. This fraction was partially translocated to the leaves, but most o f the residues remained in the roots (90.3% of absorbed C-14). In whea t, a total of 45.6% was transformed to nonextractable residues. The so luble radioactivity in the roots consisted of nearly equal amounts of the glucosides and the N-malonyl conjugate. The processes observed in soybean and wheat roots resembled those of the respective cell suspens ion cultures published previously.