Growth-Regulating Chemicals Persist in Plants: Qualitative Bioassay

Science  14 Jun 1963:
Vol. 140, Issue 3572, pp. 1212-1213
DOI: 10.1126/science.140.3572.1212


Scions from untreated tomato plants were grafted on plants treated with 2,4-dichlorophenoxyacetic acid by dipping one leaf in a solution containing 1000 parts per million. Subsequent malformations of the scion shoot and leaves were used as criteria of the presence of this chemical. The chemical or a substance causing similar symptoms persisted in the plant in physiologically active amounts for approximately 60 days.