The absorption and translocation of diclofop‐methyl and amitrole in wheat and oat roots

Abstract

The absorption and translocation of diclofop‐methyl (methyl 2‐[4(2′,4′‐dichlorophenoxy)phenoxy]propanoate) was examined by using a specially designed treatment apparatus that separated excised roots or roots of seedlings into four zones. [14C]‐Diclofop‐methyl was absorbed along the entire root length of both wheat (Triticum aestivum L.) and oat (Avena sativa L.). In both species, absorption was greatest in the apical region of the root. Absorption by the apical region of wheat roots was more than three times greater than the basal portions, and more than twice as great as the apical region of oat roots. Less than 5% of the absorbed diclofop‐methyl was translocated in both wheat and oat roots. Diclofop‐methyl and diclofop(2‐[4(2′,4′‐dichlorophenoxy)phenoxy]propanoic acid) were the predominant translocated forms. The absorption and translocation of amitrole (3‐amino‐1,2,4‐triazole) were also examined. Amitrole was absorbed along the entire length of wheat roots and translocated primatily in the basipetal direction. The usefulness of the specially designed apparatus for biochemical and physiological studies is discussed.