Effect of cations on germination & germ tube development of Puccinia coronata uredospores

Abstract

Evidence is presented that the cation composition of artificial substrates influences the germination and germ tube differentiation of uredospores of P. coronata. Zn and H ion toxicities were antagonized by added Ca and Mg. Hydrogen ions and the alkaline earth cations affected the ability of Zn to induce differentiation of infection structures. However, Zn alone was effective if its activity was properly controlled by amino acids acting as metal buffers. It is suggested that the observed cation interactions in germ tube growth and differentiation may involve displacement of native cations.