Quantitative Determination of C14 -picloram Distribution in Girdled Bean Plants

摘要

Liquid scintillation techniques were used in conjunction with autoradiography and girdling to study C14-picloram movement in Black Valentine beans following application to the primary leaf. Quantitative determinations were made of tissue samples from eight locations on each plant after 48 hours of treatment. Migration from the phloem to the xylem is suggested as a major mode of picloram translocation in the bean plant. Picloram's rapid distribution throughout the plant in most species may be due to the fact that it readily utilizes both xylem and phloem in both foliar and root application. The translocation of picloram cannot be explained on the basis of movement solely within either the symplast or the apoplast, but instead involves the entire conduction system of the plant. (Author)