Effect of Direct Current on Cells of Root Tip of Canada Field Pea

A method of subjecting roots in moist air to the direct electric current has been devised which makes it possible to control and accurately measure the current actually flowing through the root. There is no evidence that under such conditions roots behave differently from those in soil or liquid if subjected to the same current intensity. 2. Combinations of current intensity and time factors have been determined for producing death of the cells of roots, and the death curve plotted. 3. Cytological preparations of treated roots show a migration of cell contents (with few exceptions) toward the positive electrode. 4. The migratory effect (transfer of material) is not the same for all regions of the root. With one-tenth of time of death current, the cells immediately back of the root cap show little effect, those a little older (1 mm. back) greatest effect, and the cells with large vacuoles no or little effect as to cytoplasm. 5. It is suggested that, with addition of water, more free ions may occur to conduct the current; that the protoplasts of the primordial meristem are in a state of gel. 6. It is further suggested that the difference in true acidity, H-ion concentration of various protoplasts, may account for occasional different behavior of adjacent cells. 7. The theory of electrophoresis probably accounts for the migration phenomena, assuming that the constituent colloidal particles of protoplasm bear an electric charge. 8. Assuming an electric charge carried by such particles, it would follow that the particles of the cytoplasm of the cells of the roots of the Canada Field Pea bear a negative charge, and that the chromatin particles, in some cases only, may bear a positive charge.