Polyacrylamide Gel Electrophoresis (PAGE) and Densitometric Measurement of Enzyme Activity of the Pea Root Pathogen Aphanomyces euteiches in Pea Roots

A new method to measure enzyme activity of the fungal root pathogen Aphanomyces euteiches in pea roots is described. The specific enzymes of the fungus and the host were separated by polyacrylamide gel electrophoresis (PAGE) and the activity of fungal Glucose-6- phosphate dehydrogenase and Phosphoglucomutase were quantified by densitometry. Fungal activity could be correlated to the percentage infected root length and to the disease symptoms ofthe plants. The activity of ^. euteiches was studied in a time course experiment with increasing levels of zoospore inoculum. The results indicated that an increase in inoculum level resulted in a faster disease development in the plants. The relation between fungal enzyme activity and infection level is discussed.