Effects of Nonionic Surfactants on Root Growth and Cation Uptake

Surfactants are frequently employed by biological investigators to reduce the surface tension of aqueous solutions and to bring about ready wetting of tissues. Maximum expression of this property is attained at low surfactant concentrations, though the effective concentration varies somewhat between preparations. In some situations the role of the surfactant is that of a solubility aid or stabilizer of a 2-phase system, in which case higher concentrations may be necesssary. In the investigations reported here we confined our attention to nonionic surfactants, on the assumption that they would be less likely to be retained by plant tissues than cationic or anionic compounds. Our primary interest was with effects on root growth and function. Materials and Methods