The in vitro produced single species cultures were provided in Petri plates in association with Ri T-DNA-transformed carrot (Daucus carota, clone DC2) roots. They were
maintained on the modified Strullu–Romand (MSR) medium (Declerck et al. 1998) and solidified with 3 g l−1 Phytagel (Sigma-Aldrich, USA). The Petri plates were incubated in an inverted position in the dark at 27 °C. After 5 months, hundreds to thousands of spores were obtained in each Petri plate