Fig. 4

Effects of PAs (Spd and Spm) on colony growth and zoospore germination of P. sojae. a Inhibition of P. sojae hyphal growth by Spd or Spm. Mock represents treatment with ddH₂O. Scale bar, 1 cm. c Inhibition of P. sojae zoospore germination by Spd (1 mg/mL) or Spm (1 mg/mL). Mock represents treatment with ddH₂O. Scale bar, 50 μm. b, d Statistics of colony diameters and zoospore germination rates of P. sojae. Error bar represents mean ± SD, n = 8, n represents sample number. All the experiments were performed three times (biological replicates) with similar results. The data were analyzed by Shapiro–Wilk test to determine the Normality and Lognormality Tests across groups, and then analyzed by one-way ANOVA with post-hoc Dunnett's multiple comparisons test for groups that had passed the normality test (**P < 0.01). The exact n, SD values, and P values are shown in the data