Fig. 3.

Effects of diacetylphloroglucinol (DAPG) and dipropylphloroglucinol (DPPG) on motility inhibition, lysis and germination of Aphanomyces cochlioides. DAPG or DPPG were first dissolved in a small quantity of DMSO and then serially diluted with distilled water. Appropriate amounts of a sample suspension were added to the aqueous zoospore suspension. The final DMSO concentration was always less than 1% in the zoospore suspension. The time course of changes of zoospores was observed microscopically (magnification ×20) for up to 1 h after the treatment, and the percentages of activity were calculated as described previously (Islam et al. 2005). DMSO alone (final concentration in the zoospore suspension, 1%) was used as the control and did not cause any motility inhibition and lysis of the zoospores. The data are the averages ± standard errors of at least three replications for each dose of the tested compound