Translocation of Radioactive 2,4-D in Western Ragweed (Ambrosia Psilostachya)

Abstract

The purpose of the study was to determine if foliar applied 2,4-D is translocated in young western ragweed plants. Rhizomes of western ragweed were obtained in the field and grown in a sunroom. The plants were kept well watered and provided additional light from incandescent lamps. Radioactive 2,4-D solution in alcohol was applied to the leaves . Radineutographs were made and radioactive measurements were taken of treated plants. The counting equipment was a 455 Lionel Scaler. The bulk of the radioactive 2,4-D was retained in the treated leaves. Radioactive 2,4-D was found predominately in the upper portions of each plant. No translocation of radioactive 2,4-D to rhizomes or roots was detected . Under the conditions of the experiment there was a movement of organic solutes from rhizomes to leaves and meristems. When 2, 4-D was applied to the western ragweed any amount that was translocated accompanied these solutes.