Comparison of the responses of growing hyphae of R. solani to 2 x 10-7 M CA, 2 x 10-5 M NEM and 2 x 10-5 M PCMB. Each line represents 10 different hyphae followed during the first 5 minutes after treatment. Significant differences (P = 0.05) between each point are indicated by different letter designations.