Figure 5.

P. polycephalum maze-solving behavioral assay. Plasmodia were inoculated into the most peripheral channel of mazes containing either oat or VoHR5 hairy root in the central chamber. Mazes with empty central chambers were used as a control and completion was scored according to the arrival at the central chamber. (A) Schematic representation of the two optimal shortest paths to maze completion. α, site of plasmodium inoculation, β, central chamber. (B) Hairy root biomass augments the maze-solving behavior of P. polycephalum. After 36 h, plasmodia inoculated into control and oat-containing assays completed 1.5 and 10% of the respective mazes whereas plasmodia inoculated into assays containing hairy root achieved 69% maze completion. After 48 h, plasmodia completed 5% of control and 38% of oat-containing mazes whereas 75% of hairy root mazes were completed by this time. Data represent the means ± SD of three independent experiments containing at least twenty replicates each (^*p≤0.05, ^***P≤0.001, One-Way ANOVA with Tukey's post-test with a 95% confidence interval. Detailed statistical information is provided in Table S2). (C) Exemplary results of maze-solving behavior in assay plates containing oat in the central chamber after 36 h. Plasmodia explored all possible paths with no apparent directionality. In some experiments, plasmodia established a leading front upon detection of oat diffusion into the agar but did not complete the maze at the time of sampling (D) Exemplary results of maze-solving behavior in assay plates containing hairy root in the central chamber after 36 h. Plasmodia were routed via the two optimal shortest paths to the central chamber end point.