Effect of Certain Dyes on the Growth In vitro of Virus Tumor Tissue from Rumex acetosa

Abstract

1. The effect of various dyes on the growth of virus tumor tissue from the roots of Rumex acetosa L. was tested by adding the dyes to a basal medium and culturing the tissue on these substrates for 3 weeks. 2. Methylene blue, crystal violet, and malachite green inhibited growth at concentrations above 0.01 p.p.m. and had no effect at lower levels. Neutral red was slightly inhibitory (about 20%) at 0.1 p.p.m. and higher, but higher concentrations did not result in greater inhibition. Trypan blue, pyronin Y, azure A, and methyl green caused a stimulation of growth at concentrations of 0.01 and/or 0.1 p.p.m. 3. The effect of these dyes on the growth of the tumor tissue was not permanent. When the tissue was placed on the basal medium, after having been grown on a medium containing a dye, the growth rate returned to normal. 4. Unlike most other compounds, the dyes had no effect on the color of the tumor tissue, even when used at inhibitory concentrations.