Figure 2: The presence of mycelium enables bacterial growth and spore germination.

(a) Scheme of the experimental procedure providing information about vegetative growth and germination in presence of mycelium. Total cell number was determined as c.f.u. after cell detachment from the wafer and plating on agar. Spores were obtained by counting c.f.u. after heat-inactivation of the vegetative cells. (b) c.f.u. of B. subtilis after detachment from the control wafer (no contact to mycelium) and wafers overgrown by P. ultimum, F. oxysporum or Lyophyllum sp. Karsten. The dashed line shows the number of c.f.u. applied to the wafer with the inoculum. In presence of mycelium, the number of total c.f.u. increased compared with the control. Bars show the average number of c.f.u. and error bars indicate the s.d. (c) Respective proportions of B. subtilis spores, calculated by dividing the number of spore c.f.u. by the total cell c.f.u. determined in b. The bars show the mean of the quotients for the three replicates and the s.d. The number of spores was different from the number of total cells for the respective strain but did not differ for the control.