A Comparative Study of Enzymes in Resting and Germinating Uredospores of Two Species of Rust Fungi

In the research to be described, it was decided to follow changes in protein concentration and in the activities of certain enzymes of common respiratory pathways during germination of uredospores of the wheat stem and bean rust fungi. Techniques known to give good spore breakage and good germination were employed. Spore breakage approaching 100% is desirable. This would insure that differences in protein concentration and enzyme activities which may be observed at different germination periods are not caused by uncertainties in the extent of breakage, but rather, are due to significant changes with germination. Similarly, conditions for spore germination have to be used so that high percentage of synchronous germination occurs. For reliable comparisons at different germination periods, spores from the same lot must be used. Another object of this research was to investigate whether the endogenous carbohydrates released upon germination do inhibit certain respiratory pathways, which are undoubtedly active during germination. If these compounds were found to cause inhibition, then, their release at the onset of germination may be taken as an indication of germination regulation by endogenous substrates. Advisor: J. M. Dal