An Inhibitor of Salt Absorption in the Root Tissues of Red Beet

The absorption of manganese ions by discs of beet-root tissue occurs in two phases. Evidence suggests that the first is physical in nature, the second physiological. The interval between the two phases becomes longer as the thickness of the discs is increased and reasons are given for attributing this to the presence of an inhibitor of the physiological absorption process. Aqueous extracts of beet-root contain an inhibitor of ion absorption which also delays the germination of mustard and cress seeds. The extract does not affect the respiration rate of beet-root tissue.