FIG 6.

Effects of plant root exudates on swimming motility of P. luminescens 1° and 2° cells. On plates containing MeOH-Ex, 2° cells showed a significantly stronger response in terms of increased swimming activity than 1° cells. The recorded swimming diameters were even bigger than those observed with the positive-control P. fluorescens WS1750. (A) Pictures of soft-agar swimming plates supplemented with MeOH-Ex after 24 h and 48 h. (B) Graphical depiction of swimming diameters of 1° and 2° cells as well as the WS1750 strain. Error bars represent standard deviations of three independently performed experiments. **, P < 0.01.