TRANSLOCATION OF AMINOTRIAZOLE AND DALAPON IN AGROPYRON REPENS (L) BEAUV

Summary. Tracer studies using single drops of solutions containing 3–amino‐1,2,4–triazole‐5–14C (aminotriazole‐14C) or 2,2–dichloropropionic acid‐2–14C (datapon‐14C) revealed that in couch plants (Agropyron repens (L.) Beauv.) growing under field conditions in the autumn and at the stage where the aerial shoots were 40–50 cm long, both compounds moved in both symplast and apoplast. Dalapon was less mobile in the symplast than aminotriazole and only negligible amounts of dalapon were translocated to the rhizomes. The nodes of the treated shoots appeared to act as barriers to translocation, a phenomenon more pronounced for dalapon than for aminotriazole. Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully‐expanded leaf. In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots. Copyright © 1969, Wiley Blackwell. All rights reserved